Category Archives: Hydrogen

How do technology companies sell stuff?

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As the owner of a technology company, REB Research, hydrogen generators and hydrogen purifiers, I spend a fair amount of time trying to sell my stuff, and wondering how other companies connect to potential customers and sell to them. Sales is perhaps the most important area of business success, the one that makes or breaks most businesses — but it was sadly ignored in my extensive college education. Business books are hardly better: they ignore the salesmen (and women); you’re left to imagine sales and profit came of themselves by the insight of the great leader. The great, successful internet companies are applauded for giving away services, and the failed interned companies are barely mentioned. And hardly any book mentions smaller manufacturing businesses, like mine.

So here are some sales thoughts: things I tried, things that worked, and didn’t. I started my company, REB Research, about 20 years ago as a professor at Michigan State University. I figured I knew more about hydrogen purifiers than most of my colleagues, and imagined this knowledge would bring me money (big mistake: I needed customers and profitable sales). My strategy was to publish papers on hydrogen and get some patents as a way to build credibility (worked reasonably well: I write well, do research well, and I’m reasonably inventive). Patents might have been a better strategy if I had not then allowed my patents to be re-written by lawyers. I built the company. while still a professor (a good idea, I think).

When I realized I needed sales, I decided to use trade fairs, conferences, and ads as the big companies did. Most of my budget went for ads in The Thomas Register of American Manufacturing, a fantastically large compendium of who did or sold what (it worked OK, but was since rendered obsolete by the internet). I bought $1500 worth of ads, and got 2 small lines plus a 1/8 page. That’s where I got my sales until the internet cam along. In retrospect, I suspect I should have bought more ads.

William Hamilton cartoon from the new-yorker. I sure wish I could make deals.

William Hamilton cartoon from the new-yorker.

My other big expense was trade fairs. Many big companies sold at trade fairs, events that are widely attended in my field. Sorry to say, I never found customers at these fairs, even when the fairs were dedicated to hydrogen, everyone who’d come by was was selling, and no one was buying, as best I could tell.Somehow, my bigger competitors (also at the fairs) seemed to get interest but I’m not sure if they got sales there. They seem to find sales somewhere, though. Is it me? Am I at the wrong fairs, or are fairs just a scam where no one wins but the organizers? I don’t know. Last month, I spent $2000 for a booth in Ann Arbor, MI, including $350 for inclusion into the promoter’s book and $400 for hand-out literature. As with previous events, few people came by and none showed anything like interest, I got no e-mail addresses and no sales. Some hungry students wandered the stalls for food and freebees, but there was not one person with money in his/her pocket and a relevant project to spend it on. I doubt anyone read the literature they took.

To date, virtually all of my sales have come from the internet. I got on the internet early, and that has helped my placement in Google. I’ve never bought a google ad, but this may change. Instead I was lucky. About 20 years ago, 1994?, I attended a conference at Tufts on membrane reactors, and stayed at a bed-and-breakfast. After the conference let out, the owner of the BnB suggested I visit something that was new at Harvard; a cyber cafe, the second one in the US. They had Macintosh computers and internet explorer a year before the company went public. I was hooked, went home, learned html, and wrote a web-site. I bought my domain name shortly thereafter.

The problem, I don’t know the next big thing. Twitter? Facebook? LinkedIn? I’m on 2 of these 3, and have gotten so sales from social media. I started a blog (you’re reading it), but I still wonder, why are the bigger companies selling more? The main difference I see is they attend a lot more product fairs than I do, have slicker web-sties (not very good ones, I think), and they do print advertising. Perhaps they match their fairs to their products better, or have a broader range of products. People need to see my products somewhere, but where? My latest idea: this week I bought HydrogenPurifier.com. Send me advice, or wish me luck.

Robert E. Buxbaum, flailing entrepreneur, September 10, 2014. Here’s a feedback form, the first time I’m adding one. 

Getting rid of hydrogen

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Though most of my company’s business is making hydrogen or purifying it, or consulting about it, we also provide sorbers and membranes that allow a customer to get rid of unwanted hydrogen, or remove it from a space where it is not wanted. A common example is a customer who has a battery system for long-term operation under the sea, or in space. The battery or the metal containment is then found to degas hydrogen, perhaps from a corrosion reaction. The hydrogen may interfere with his electronics, or the customer fears it will reach explosive levels. In one case the customer’s system was monitoring deep oil wells and hydrogen from the well was messing up its fiber optic communications.

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Pd-coated niobium screws used to getter hydrogen from electronic packages.

For many of these problems, the simplest solution is an organic hydrogen getter of palladium-catalyst and a labile unsaturated hydrocarbon, e.g. buckminsterfullerene. These hydrogen getters are effective in air or inert gas at temperatures between about -20°C and 150°C. When used in an inert gas the organic is hydrogenated, there is a finite amount of removal per gram of sober. When used in air the catalyst promotes the water-forming reaction, and thus there is a lot more hydrogen removal. Depending on the organic, we can provide gettering to lower temperatures or higher. We’ve a recent patent on an organo-palladium gel to operate to 300°C, suitable for down-well hydrogen removal.

At high temperatures, generally above 100*C, we generally suggest an inorganic hydrogen remover, e.g. our platinum ceria catalyst. This material is suitable for hydrogen removal from air, including from polluted air like that in radioactive waste storage areas. Platinum catalyst works long-term at temperatures between about 0°C and 600°C. The catalyst-sorber also works without air, reducing Ce2O3 to CeO and converting hydrogen irreversibly to water (H2O). As with the organo-Pd getters, there is a finite amount of hydrogen removal per gram when these materials are used in a sealed environment.

Low temperature, Pd-grey coated, Pd-Ag membranes made for the space shuttle to remove hydrogen from the drinking water at room temperature. The water came from the fuel cells.

Low temperature, metal membranes made for NASA to remove H2 from  drinking water at room temperature.

Another high temperature hydrogen removal option is metallic getters, e.g. yttrium or vanadium-titanium alloy. These metals require temperatures in excess of 100°C to be effective, and typically do not work well in air. They are best suited for removing hydrogen a vacuum or inert gas, converting it to metallic hydride. The thermodynamics of hydriding is such that, depending on the material, these getters can extract hydrogen even at temperatures up to 700°C, and at very low hydrogen pressures, below 10-9 torr. For operation in air or at 100-400°C we typically provide these getters coated with palladium to increase the hydrogen sorption rate. A fairly popular product is palladium-coated niobium screws 4-40 x 1/4″. Each screw will remove over 2000 sec of hydrogen at temperatures up to 400°C. We also provide oxygen, nitrogen and water getters. They work on the same principle, but form metallic oxides or nitrides instead of hydrides.

Our last, and highest-end, hydrogen-removal option is to provide metallic membranes. These don’t remove the hydrogen as such, but transfer it elsewhere. We’ve provided these for the space shuttle, and to the nuclear industry so that hydrogen can be vented from nuclear reactors before it has a chance to build up and case damage or interfere with heat transfer. Because nothing is used up, these membranes work, essentially forever. The Fukushima reactor explosions were from corrosion-produced hydrogen that had no acceptable way to vent.

Please contact us for more information, e.g. by phone at 248-545-0155, or check out the various sorbers in our web-site. Robert Buxbaum, May 5, 2014.

Nuclear fusion

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I got my PhD at Princeton University 33 years ago (1981) working on the engineering of nuclear fusion reactors, and I thought I’d use this blog to rethink through the issues. I find I’m still of the opinion that developing fusion is important as the it seems the best, long-range power option. Civilization will still need significant electric power 300 to 3000 years from now, it seems, when most other fuel sources are gone. Fusion is also one of the few options for long-range space exploration; needed if we ever decide to send colonies to Alpha Centauri or Saturn. I thought fusion would be ready by now, but it is not, and commercial use seems unlikely for the next ten years at least — an indication of the difficulties involved, and a certain lack of urgency.

Oil, gas, and uranium didn’t run out like we’d predicted in the mid 70s. Instead, population growth slowed, new supplies were found, and better methods were developed to recover and use them. Shale oil and fracking unlocked hydrocarbons we thought were unusable, and nuclear fission reactors got better –safer and more efficient. At the same time, the more we studied, the clearer it came that fusion’s technical problems are much harder to tame than uranium fission’s.

Uranium fission was/is frighteningly simple — far simpler than even the most basic fusion reactor. The first nuclear fission reactor (1940) involved nothing more than uranium pellets in a pile of carbon bricks stacked in a converted squash court at the University of Chicago. No outside effort was needed to get the large, unstable uranium atoms split to smaller, more stable ones. Water circulating through the pile removed the heat released, and control was maintained by people lifting and lowering cadmium control rods while standing on the pile.

A fusion reactor requires high temperature or energy to make anything happen. Fusion energy is produced by combining small, unstable heavy hydrogen atoms into helium, a bigger more stable one, see figure. To do this reaction you need to operate at the equivalent of about 500,000,000 degrees C, and containing it requires (typically) a magnetic bottle — something far more complex than a pile of graphic bricks. The reward was smaller too: “only” about 1/13th as much energy per event as fission. We knew the magnetic bottles were going to be tricky, e.g. there was no obvious heat transfer and control method, but fusion seemed important enough, and the problems seemed manageable enough that fusion power seemed worth pursuing — with just enough difficulties to make it a challenge.

Basic fusion reaction: deuterium + tritium react to give helium, a neutron and energy.

Basic fusion reaction: deuterium + tritium react to give helium, a neutron and energy.

The plan at Princeton, and most everywhere, was to use a TOKAMAK, a doughnut-shaped reactor like the one shown below, but roughly twice as big; TOKAMAK was a Russian acronym. The doughnut served as one side of an enormous transformer. Hydrogen fuel was ionized into a plasma (a neutral soup of protons and electrons) and heated to 300,000,000°C by a current in the TOKOMAK generated by varying the current in the other side of the transformer. Plasma containment was provided by enormous magnets on the top and bottom, and by ring-shaped magnets arranged around the torus.

As development went on, we found we kept needing bigger and bigger doughnuts and stronger and stronger magnets in an effort to balance heat loss with fusion heating. The number density of hydrogen atoms per volume, n, is proportional to the magnetic strength. This is important because the fusion heat rate per volume is proportional to n-squared, n2, while heat loss is proportional to n divided by the residence time, something we called tau, τ. The main heat loss was from the hot plasma going to the reactor surface. Because of the above, a heat balance ratio was seen to be important, heat in divided by heat out, and that was seen to be more-or-less proportional to nτ. As the target temperatures increased, we found we needed larger and larger nτ reactors to make a positive heat balance. And this translated to ever larger reactors and ever stronger magnetic fields, but even here there was a limit, 1 billion Kelvin, a thermodynamic temperature where the fusion reaction went backward and no energy was produced. The Princeton design was huge, with super strong, super magnets, and was operated at 300 million°C, near the top of the reaction curve. If the temperature went above or below this temperature, the fire would go out. There was no room for error, but relatively little energy output per volume — compared to fission.

Fusion reaction options and reaction rates.

Fusion reaction options and reaction rates.

The most likely reaction involved deuterium and tritium, referred to as D and T. This was the reaction of the two heavy isotopes of hydrogen shown in the figure above — the same reaction used in hydrogen bombs, a point we rarely made to the public. For each reaction D + T –> He + n, you get 17.6 million electron volts (17.6 MeV). This is 17.6 million times the energy you get for an electron moving over one Volt, but only 1/13 the energy of a fission reaction. By comparison, the energy of water-forming, H2 + 1/2 O2 –> H2O, is the equivalent of two electrons moving over 1.2 Volts, or 2.4 electron volts (eV), some 8 million times less than fusion.

The Princeton design involved reacting 40 gm/hr of heavy hydrogen to produce 8 mol/hr of helium and 4000 MW of heat. The heat was converted to electricity at 38% efficiency using a topping cycle, a modern (relatively untried) design. Of the 1500 MWh/hr of electricity that was supposed to be produced, all but about 400 MW was to be delivered to the power grid — if everything worked right. Sorry to say, the value of the electricity did not rise anywhere as fast as the cost of the reactor and turbines. Another problem: 1100 MW was more than could be easily absorbed by any electrical grid. The output was high and steady, and could not be easily adjusted to match fluctuating customer demand. By contrast a coal plant’s or fuel cell’s output could be easily adjusted (and a nuclear plant with a little more difficulty).

Because of the need for heat balance, it turned out that at least 9% of the hydrogen had to be burnt per pass through the reactor. The heat lost per mol by conduction to the wall was, to good approximation, the heat capacity of each mol of hydrogen ions, 82 J/°C mol, times the temperature of the ions, 300 million °C divided by the containment time, τ. The Princeton design was supposed to have a containment of about 4 seconds. As a result, the heat loss by conduction was 6.2 GW per mol. This must be matched by the molar heat of reaction that stayed in the plasma. This was 17.6 MeV times Faraday’s constant, 96,800 divided by 4 seconds (= 430 GW/mol reacted) divided by 5. Of the 430 GW/mol produced in fusion reactions only 1/5 remains in the plasma (= 86 GW/mol) the other 4/5 of the energy of reaction leaves with the neutron. To get the heat balance right, at least 9% of the hydrogen must react per pass through the reactor; there were also some heat losses from radiation, so the number is higher. Burn more or less percent of the hydrogen and you had problems. The only other solution was to increase τ > 4 seconds, but this meant ever bigger reactors.

There was also a material handling issue: to get enough fuel hydrogen into the center of the reactor, quite a lot of radioactive gas had to be handled — extracted from the plasma chamber. These were to be frozen into tiny spheres of near-solid hydrogen and injected into the reactor at ultra-sonic velocity. Any slower and the spheres would evaporate before reaching the center. As 40 grams per hour was 9% of the feed, it became clear that we had to be ready to produce and inject 1 pound/hour of tiny spheres. These “snowballs-in-hell” had to be small so they didn’t dampen the fire. The vacuum system had to be able to be big enough to handle the lb/hr or so of unburned hydrogen and ash, keeping the pressure near total vacuum. You then had to purify the hydrogen from the ash-helium and remake the little spheres that would be fed back to the reactor. There were no easy engineering problems here, but I found it enjoyable enough. With a colleague, I came up with a cute, efficient high vacuum pump and recycling system, and published it here.

Yet another engineering challenge concerned the difficulty of finding a material for the first-wall — the inner wall of the doughnut facing the plasma. Of the 4000 MW of heat energy produced, all the conduction and radiation heat, about 1000 MW is deposited in the first wall and has to be conducted away. Conducting this heat means that the wall must have an enormous coolant flow and must withstand an enormous amount of thermal stress. One possible approach was to use a liquid wall, but I’ve recently come up with a rather nicer solid wall solution (I think) and have filed a patent; more on that later, perhaps after/if the patent is accepted. Another engineering challenge was making T, tritium, for the D-T reaction. Tritium is not found in nature, but has to be made from the neutron created in the reaction and from lithium in a breeder blanket, Li + n –> He + T. I examined all possible options for extracting this tritium from the lithium at low concentrations as part of my PhD thesis, and eventually found a nice solution. The education I got in the process is used in my, REB Research hydrogen engineering business.

Man inside the fusion reactor doughnut at ITER. He'd better leave before the 8,000,000°C plasma turns on.

Man inside the fusion reactor doughnut at ITER. He’d better leave before the 8,000,000°C plasma turns on.

Because of its complexity, and all these engineering challenges, fusion power never reached the maturity of fission power; and then Three-mile Island happened and ruined the enthusiasm for all things nuclear. There were some claims that fusion would be safer than fission, but because of the complexity and improvements in fission, I am not convinced that fusion would ever be even as safe. And the long-term need keeps moving out: we keep finding more uranium, and we’ve developed breeder reactors and a thorium cycle: technologies that make it very unlikely we will run out of fission material any time soon.

The main, near term advantage I see for fusion over fission is that there are fewer radioactive products, see comparison.  A secondary advantage is neutrons. Fusion reactors make excess neutrons that can be used to make tritium, or other unusual elements. A need for one of these could favor the development of fusion power. And finally, there’s the long-term need: space exploration, or basic power when we run out of coal, uranium, and thorium. Fine advantages but unlikely to be important for a hundred years.

Robert E. Buxbaum, March 1, 2014. Here’s a post on land use, on the aesthetics of engineering design, and on the health risks of nuclear power. The sun’s nuclear fusion reactor is unstable too — one possible source of the chaotic behavior of the climate. Here’s a control joke.

Toxic electrochemistry and biology at home

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A few weeks back, I decided to do something about the low quality of experiments in modern chemistry and science sets; I posted to this blog some interesting science experiments, and some more-interesting experiments that could be done at home using the toxic (poisonous dangerous) chemicals available under the sink or on the hardware store. Here are some more. As previously, the chemicals are toxic and dangerous but available. As previously, these experiments should be done only with parental (adult) supervision. Some of these next experiments involve some math, as key aspect of science; others involve some new equipment as well as the stuff you used previously. To do them all, you will want a stop watch, a volt-amp meter, and a small transformer, available at RadioShack; you’ll also want some test tubes or similar, clear cigar tubes, wire and baking soda; for the coating experiment you’ll want copper drain clear, or copper containing fertilizer and some washers available at the hardware store; for metal casting experiment you’ll need a tin can, pliers, a gas stove and some pennies, plus a mold, some sand, good shoes, and a floor cover; and for the biology experiment you will need several 9 V batteries, and you will have to get a frog and kill it. You can skip any of these experiments, if you like and do the others. If you have not done the previous experiments, look them over or do them now.

1) The first experiments aim to add some numerical observations to our previous studies of electrolysis. Here is where you will see why we think that molecules like water are made of fixed compositions of atoms. Lets redo the water electrolysis experiment now with an Ammeter in line between the battery and one of the electrodes. With the ammeter connected, put both electrodes deep into a solution of water with a little lye, and then (while watching the ammeter) lift one electrode half out, place it back, and lift the other. You will find, I think, that one of the other electrode is the limiting electrode, and that the amperage goes to 1/2 its previous value when this electrode is half lifted. Lifting the other electrode changes neither the amperage or the amount of bubbles, but lifting this limiting electrode changes both the amount of bubbles and the amperage. If you watch closely, though, you’ll see it changes the amount of bubbles at both electrodes in proportion, and that the amount of bubbles is in promotion to the amperage. If you collect the two gasses simultaneously, you’ll see that the volume of gas collected is always in a ratio of 2 to 1. For other electrolysis (H2 and Cl2) it will be 1 to1; it’s always a ratio of small numbers. See diagram below on how to make and collect oxygen and hydrogen simultaneously by electrolyzing water with lye or baking soda as electrolyte. With lye or baking soda, you’ll find that there is always twice as much hydrogen produced as oxygen — exactly.

You can also do electrolysis with table salt or muriatic acid as an electrolyte, but for this you’ll need carbon or platinum electrodes. If you do it right, you’ll get hydrogen and chlorine, a green gas that smells bad. If you don’t do this right, using a wire instead of a carbon or platinum electrode, you’ll still get hydrogen, but no chlorine. Instead of chlorine, you’ll corrode the wire on that end, making e.g. copper chloride. With a carbon electrode and any chloride compound as the electrolyte, you’ll produce chlorine; without a chloride electrolyte, you will not produce chlorine at any voltage, or with any electrode. And if you make chlorine and check the volumes, you’ll find you always make one volume of chlorine for every volume of hydrogen. We imagine from this that the compounds are made of fixed atoms that transfer electrons in fixed whole numbers per molecule. You always make two volumes of hydrogen for every volume of oxygen because (we think) making oxygen requires twice as many electrons as making hydrogen.

At home electrolysis experiment

At home electrolysis experiment

We get the same volume of chlorine as hydrogen because making chlorine and hydrogen requires the same amount of electrons to be transferred. These are the sort of experiments that caused people to believe in atoms and molecules as the fundamental unchanging components of matter. Different solutes, voltages, and electrodes will affect how fast you make hydrogen and oxygen, as will the amount of dissolved solute, but the gas produced are always the same, and the ratio of volumes is always proportional to the amperage in a fixed ratio of small whole numbers.

As always, don’t let significant quantities of use hydrogen and oxygen or pure hydrogen and chlorine mix in a closed space. Hydrogen and oxygen is quite explosive brown’s gas; hydrogen and chlorine are reactive as well. When working with chlorine it is best to work outside or near an open window: chlorine is a poison gas.

You may also want to try this with non-electrolytes, pure water or water with sugar or alcohol dissolved. You will find there is hardly any amperage or gas with these, but the small amount of gas produced will retain the same ratio. For college level folks, here is some physics/math relating to the minimum voltage and relating to the quantities you should expect at any amperage.

2) Now let’s try electro-plating metals. Using the right solutes, metals can be made to coat your electrodes the same way that bubbles of gas coated your electrodes in the experiments above. The key is to find the right chemical, and as a start let me suggest the copper sulphate sold in hardware stores to stop root growth. As an alternative copper sulphate is often sold as part of a fertilizer solution like “Miracle grow.” Look for copper on the label, or for a blue color fertilizer. Make a solution of copper using enough copper so that the solution is recognizably green, Use two steel washers as electrodes (that is connect the wires from your battery to the washers) and put them in the solution. You will find that one side turns red, as it is coated with copper. Depending on what else your copper solution contained, bubbles may appear at the other washer, or the other washer will corrode. 

You are now ready to take this to a higher level — silver coating. take a piece of silver plated material that you want to coat, and clean it nicely with soap and water. Connect it to the electrode where you previously coated copper. Now clean out the solution carefully. Buy some silver nitrate from a drug store, and dissolve a few grams (1/8 tsp for a start) in pure water; place the silverware and the same electrodes as before, connected to the battery. For a nicer coat use a 1 1/2 volt lantern battery; the 6 V battery will work too, but the silver won’t look as nice. With silver nitrate, you’ll notice that one electrode produces gas (oxygen) and the other turns silvery. Now disconnect the silvery electrode. You can use this method to silver coat a ring, fork, or cup — anything you want to have silver coated. This process is called electroplating. As with hydrogen production, there is a proportional relationship between the time, the amperage and the amount of metal you deposit — until all the silver nitrate in solution is used up.

As a yet-more complex version, you can also electroplate without using a battery. This was my Simple electroplating (presented previously). Consider this only after you understand most everything else I’ve done. When I saw this the first time in high school I was confused.

3) Casting metal objects using melted pennies, heat from a gas stove, and sand or plaster as a cast. This is pretty easy, but sort of dangerous — you need parents help, if only as a watcher. This is a version of an experiment I did as a kid.  I did metal casting using lead that some plumbers had left over. I melted it in a tin can on our gas stove and cast “quarters” in a plaster mold. Plumbers no longer use lead, but modern pennies are mostly zinc, and will melt about as well as my lead did. They are also much safer.

As a preparation for this experiment, get a bucket full of sand. This is where you’ll put your metal when you’re done. Now get some pennies (1970 or later), a pair of pliers, and an empty clean tin can, and a gas stove. If you like you can make a plaster mold of some small object: a ring, a 50 piece — anything you might want to cast from your pennies. With parents’ help, light your gas stove, put 5-8 pennies in the empty tin can, and hold the can over the lit gas burner using your pliers. Turn the gas to high. In a few minutes the bottom of the can will burn and become red-hot. About this point, the pennies will soften and melt into a silvery puddle. By tilting the can, you can stir the metal around (don’t get it on you!). When it looks completely melted you can pour the molten pennies into your sand bucket (carefully), or over your plaster mold (carefully). If you use a mold, you’ll get a zinc copy of whatever your mold was: jewelry, coins, etc. If you work at it, you’ll learn to make fancier and fancier casts. Adult help is welcome to avoid accidents. Once the metal solidifies, you can help cool it faster by dripping water on it from a faucet. Don’t touch it while it’s hot!

A plaster mold can be made by putting a 50¢ piece at the bottom of a paper cup, pouring plaster over the coin, and waiting for it to dry. Tear off the cup, turn the plaster over and pull out the coin; you’ve got a one-sided mold, good enough to make a one-sided coin. If you enjoy this, you can learn more about casting on Wikipedia; it’s an endeavor that only costs 4 or 5 cents per try. As a safety note: wear solid leather shoes and cover the floor near the stove with a board. If you drop the metal on the floor you’ll have a permanent burn mark on the floor and your mother will not be happy. If you drop hot metal on your you’ll have a permanent injury, and you won’t be happy. Older pennies are made of copper and will not melt. Here’s a video of someone pouring a lot of metal into an ant-hill (kills lots of ants, makes a mold of the hill).

It's often helpful to ask yourself, "what would Dr. Frankenstein do?"

It’s nice to have assistants, friends and adult help in the laboratory when you do science. Even without the castle, it’s what Dr. Frankenstein did.

4) Bringing a dead frog back to life (sort of). Make a high voltage battery of 45 to 90 V battery by attaching 5-10, 9V batteries in a daisy chain they will snap together. If you touch both exposed contacts you’ll give yourself a wicked shock. If you touch the electrodes to a newly killed frog, the frog legs will kick. This is sort of groovy. It was the inspiration for Dr. Frankenstein (at right), who then decides he could bring a person back from the dead with “more power.” Frankenstein’s monster is brought back to life this way, but ends up killing the good doctor. Shocks are sometimes helpful reanimating people stricken by heat attacks, and many buildings have shockers for this purpose. But don’t try to bring back the long-dead. By all accounts, the results are less-than pleasing. Try dissecting the rest of the frog and guess what each part is (a world book encyclopedia helps). As I recall, the heart keeps going for a while after it’s out of the frog — spooky.

5) Another version of this shocker is made with a small transformer (1″ square, say, radioshack) and a small battery (1.5-6V). Don’t use the 90V battery, you’ll kill someone. As a first version of this shocker, strip 1″ of  insulation off of the ends of some wire 12″ long say, and attach one end to two paired wires of the transformer (there will usually be a diagram in the box). If the transformer already has some wires coming out, all you have to do is strip more insulation off the ends so 1″ is un-inuslated. Take two paired ends in your hand, holding onto the uninsulated part and touch both to the battery for a second or two. Then disconnect them while holding the bare wires; you’ll get a shock. As a nastier version, get a friend to hope the opposite pair of wires on the uninsulated parts, while you hold the insulated parts of your two. Touch your two to the battery and disconnect while holding the insulation, you will see a nice spark, and your friend will get a nice shock. Play with it; different arrangements give more sparks or bigger shocks. Another thing you can do: put your experiment near a radio or TV. The transformer sparks will interfere with most nearby electronics; you can really mess up a computer this way, so keep it far from your computer. This is how wireless radio worked long ago, and how modern warfare will probably go. The atom bomb was detonated with a spark like this.

If you want to do more advanced science, it’s a good idea to learn math. This is important for statistics, for engineering, for quantum mechanics, and can even help for music. Get a few good high school or college books and read them cover to cover. An approach to science is to try to make something cool, that sort-of works, and then try to improve it. You then decide what a better version would work like,  modify your original semi-randomly and see if you’re going in the right direction. Don’t redesign with only one approach –it may not work. Read whatever you can, but don’t believe all you read. Often books are misleading, or wrong, and blogs are worse (I ought to know). When you find mistakes, note them in the margin, and try to explain them. You may find you were right, or that the book was right, but it’s a learning experience. If you like you can write the author and inform him/her of the errors. I find mailed letters are more respectful than e-mails — it shows you put in more effort.

Robert Buxbaum, February 20, 2014. Here’s the difference between metals and non-metals, and a periodic table cup that I made, and sell. And here’s a difference between science and religion – reproducibility.

Hydrogen cars and buses are better than Tesla

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Hydrogen fueled cars and buses are as clean to drive as battery vehicles and have better range and faster fueling times. Cost-wise, a hydrogen fuel tank is far cheaper and lighter than an equivalent battery and lasts far longer. Hydrogen is likely safer because the tanks do not carry their oxidant in them. And the price of hydrogen is relatively low, about that of gasoline on a per-mile basis: far lower than batteries when the cost of battery wear-out is included. Both Presidents Clinton and Bush preferred hydrogen over batteries, but the current administration favors batteries. Perhaps history will show them correct, but I think otherwise. Currently, there is not a hydrogen bus, car, or boat making runs at Disney’s Experimental Community of Tomorrow (EPCOT), nor is there an electric bus car or boat. I suspect it’s a mistake, at least convening the lack of a hydrogen vehicle. 

The best hydrogen vehicles on the road have more range than the best electric vehicle, and fuel faster. The hydrogen powered, Honda Clarity debuted in 2008. It has a 270 mile range and takes 3-5 minutes to fuel with hydrogen at 350 atm, 5150 psi. By contrast, the Tesla S-sedan that debuted in 2012 claims only a 208 mile range for its standard, 60kWh configuration (the EPA claims: 190 miles) and requires three hours to charge using their fastest charger, 20 kW.

What limits the range of battery vehicles is that the stacks are very heavy and expensive. Despite using modern lithium-ion technology, Tesla’s 60 kWh battery weighs 1050 lbs including internal cooling, and adds another 250 lbs to the car for extra structural support. The Clarity fuel system weighs a lot less. The hydrogen cylinders weigh 150 lb and require a fuel cell stack (30 lb) and a smaller lithium-ion battery for start-up (90 lb). The net effect is that the Clarity weighs 3582 lbs vs 4647 lbs for the Tesla S. This extra weight of the Tesla seems to hurt its mileage by about 10%. The Tesla gets about 3.3 mi/kWh or 0.19 mile/lb of battery versus 60 miles/kg of hydrogen for the Clarity suggesting  3.6 mi/kWh at typical efficiencies. 

High pressure hydrogen tanks are smaller than batteries and cheaper per unit range. The higher the pressure the smaller the tank. The current Clarity fuels with 350 atm, 5,150 psi hydrogen, and the next generation (shown below) will use higher pressure to save space. But even with 335 atm hydrogen (5000 psi) a Clarity could fuel a 270 mile range with four, 8″ diameter tanks (ID), 4′ long. I don’t know how Honda makes its hydrogen tanks, but suitable tanks might be made from 0.065″ Maranging (aged) stainless steel (UTS = 350,000 psi, density 8 g/cc), surrounded by 0.1″ of aramid fiber (UTS = 250,000 psi, density = 1.6 g/cc). With this construction, each tank would weigh 14.0 kg (30.5 lbs) empty, and hold 11,400 standard liters, 1.14 kg (2.5 lb) of hydrogen at pressure. These tanks could cost $1500 total; the 270 mile range is 40% more Than the Tesla S at about 1/10 the cost of current Tesla S batteries The current price of a replacement Tesla battery pack is $12,000, subsidized by DoE; without the subsidy, the likely price would be $40,000.

Next generation Honda fuel cell vehicle prototype at the 2014 Detroit Auto Show.

Next generation Honda fuel cell vehicle prototype at the 2014 Detroit Auto Show.

Currently hydrogen is more expensive than electricity per energy value, but my company has technology to make it cheaply and more cleanly than electricity. My company, REB Research makes hydrogen generators that produce ultra pure hydrogen by steam reforming wow alcohol in a membrane reactor. A standard generator, suitable to a small fueling station outputs 9.5 kg of hydrogen per day, consuming 69 gal of methanol-water. At 80¢/gal for methanol-water, and 12¢/kWh for electricity, the output hydrogen costs $2.50/kg. A car owner who drove 120,000 miles would spend $5,000 on hydrogen fuel. For that distance, a Tesla owner would spend only $4400 on electricity, but would have to spend another $12,000 to replace the battery. Tesla batteries have a 120,000 mile life, and the range decreases with age. 

For a bus or truck at EPCOT, the advantages of hydrogen grow fast. A typical bus is expected to travel much further than 120,000 miles, and is expected to operate for 18 hour shifts in stop-go operation getting perhaps 1/4 the miles/kWh of a sedan. The charge time and range advantages of hydrogen build up fast. it’s common to build a hydrogen bus with five 20 foot x 8″ tanks. Fueled at 5000 psi., such buses will have a range of 420 miles between fill-ups, and a total tank weight and cost of about 600 lbs and $4000 respectively. By comparison, the range for an electric bus is unlikely to exceed 300 miles, and even this will require a 6000 lb., 360 kWh lithium-ion battery that takes 4.5 hours to charge assuming an 80 kW charger (200 Amps at 400 V for example). That’s excessive compared to 10-20 minutes for fueling with hydrogen.

While my hydrogen generators are not cheap: for the one above, about $500,000 including the cost of a compressor, the cost of an 80 kW DC is similar if you include the cost to run a 200 Amp, 400 V power line. Tesla has shown there are a lot of people who value clean, futuristic transport if that comes with comfort and style. A hydrogen car can meet that handily, and can provide the extra comforts of longer range and faster refueling.

Robert E. Buxbaum, February 12, 2014 (Lincoln’s birthday). Here’s an essay on Lincoln’s Gettysburg address, on the safety of batteries, and on battery cost vs hydrogen. My company, REB Research makes hydrogen generators and purifiers; we also consult.

Toxic chemistry you can do at home

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I got my start on science working with a 7 chemical, chemistry set that my sister got me when I was 7 years old (thanks Beverly). The chemicals would never be sold by a US company today — too much liability. What if your child poisons himself/herself or someone else, or is allergic, or someone chokes on the caps (anything the size of a nut has to be labeled as a hazard). Many of the experiments were called magic, and they were, in the sense that, if you did them 200 years earlier, you’d be burnt as a witch. There were dramatic color changes (phenolphthalein plus base, Prussian Blue) a time-delay experiment involving cobalt, and even an experiment that (as I recall) burst into fire on its own (glycerine plus granulated potassium permanganate).

Better evil through science. If you get good at this, the military may have use of your services.

“Better the evil you know.” If you get good at this, the military may have use of your services. Yes, the American military does science.

Science kits nowadays don’t do anything magically cool like that, and they don’t really teach chemistry, either, I think. Doing magical things requires chemicals that are reasonably reactive, and that means corrosive and/or toxic. Current kits use only food products like corn-starch or baking soda, and the best you can do with these is to make goo and/ or bubbles. No one would be burnt at the stake for this, even 300 years ago. I suppose one could design a program that used these materials to teach something about flow, or nucleation, but that would require math, and the kit producers fear that any math will turn off kids and stop their parents from spending money. There is also the issue of motivation. Much of historical chemistry was driven by greed and war; these are issues that still motivate kids, but that modern set-makers would like to ignore. Instead, current kits are supposed to be exciting in a cooperative way (whatever that means), because the kit-maker says so. They are not. I went through every experiment in my first kit in the first day, and got things right within the first week — showing off to whoever would watch. Modern kits don’t motivate this sort of use; I doubt most get half-used in a lifetime.

There are some foreign-made chemistry sets still that are pretty good. Here is a link to a decent mid-range one from England. But it’s sort of pricy, and already somewhat dumbed down. Instead, here are some cheaper, more dangerous, American options: 5 experiments you can do (kids and parents together, please) using toxic household chemicals found in our US hardware stores. These are NOT the safest experiments, just cheap ones that are interesting. I’ll also try to give some math and explanations — so you’ll understand what’s happening on a deeper level — and I’ll give some financial motivation — some commercial value.

1) Crystal Drano + aluminum. Crystal Drano is available in the hardware store. It’s mostly lye, sodium hydroxide, one of the strongest bases known to man. It’s a toxic (highly poisonous) chemical used to dissolve hair and fat in a drain. It will also dissolve some metals and it will dissolve you if you get it on yourself (if you do get it on yourself, wash it off fast with lots of water). Drano also contains ammonium nitrate (an explosive) and bits of aluminum. For the most part, the aluminum is there so that the Drano will get hot in the clogged drain (heat helps it dissolve the clog faster). I’ll explain the ammonium nitrate later. For this experiment, you’re going to want to work outside, on a dinner plate on the street. You’ll use additional aluminum (aluminum foil), and you’ll get more heat and fun gases. Fold up a 1 foot square of aluminum foil to 6″ x 4″ say, and put it on the plate (outside). Put an indent in the middle of the foil making a sort of small cup — one that can stand. Into this indent, put a tablespoon or two of water plus a teaspoon of Drano. Wait about 5 minutes, and you will see that the Drano starts smoking and the aluminum foils starts to dissolve. The plate will start to get hot and you will begin to notice a bad smell (ammonia). The aluminum foil will turn black and will continue to dissolve till there is a hole in the middle of the indent. Draino

The main reaction is 2 Al + 3 H2O –> Al2O3 + H2; that is, aluminum plus water gives you aluminum oxide (alumina), and hydrogen. The sodium hydroxide (lye) in the Drano is a catalyst in this reaction, something that is not consumed in this reaction but makes it happen faster than otherwise. The hydrogen you produce here is explosive and valuable (I explain below). But there is another reaction going on too, the one that makes the bad smell. When ammonium nitrate is heated in the presence of sodium hydroxide, it reacts to make ammonia and sodium nitrate. The reaction formula is: NH4-NO3 + NaOH –> NH3 + NaNO3 + H2O. The ammonia produced gives off a smell, something that is important for safety — the smell is a warning — and (I think) helps keep the aluminum gunk from clogging the drain by reacting with the aluminum oxide to form aluminum amine hydroxide Al2O3(NH3)2. It’s a fun experiment to watch, but you can do more if you like. The hydrogen and ammonia are flammable and is useful for other experiments (below). If you collect these gases, you can can make explosions or fill a balloon that will float. Currently the US military, and several manufacturers in Asia are considering using the hydrogen created this way to power motorcycles by way of a fuel cell. There is also the Hindenburg, a zeppelin that went around the world in the 1930s. It was kept aloft by hydrogen. The ammonia you make has value too, though toxic; if bubbled into water, it makes ammonium hydroxide NH3 + H2O –> NH4OH. This is a common cleaning liquid. Just to remind you: you’re supposed to do these experiments outside to dissipate the toxic gases and to avoid an explosion in your house. A parent will come in handy if you get this stuff on your hand or in your eye.

Next experiment: check that iron does not dissolve in Drano, but it does in acid (that’s experiment 5; done with Muriatic acid from the hardware store). Try also copper, and solder (mostly tin, these days). Metals that dissolve well in Drano are near the right of the periodic table, like aluminum. Aluminum is nearly a non-metal, and thus can be expected to have an oxide that reacts with hydroxide. Iron and steel have oxides that are bases themselves, and thus don’t react with lye. This is important as otherwise Drano would destroy your iron drain, not only the hair in it. It’s somewhat hard on copper though, so beware if you’ve a copper drain.

Thought problem: based on the formulas above figure out the right mix of aluminum, NaOH, water and Ammonium nitrate. Answer: note that, for every two atoms of aluminum you dissolve, you’ll need three molecules of water (for the three O atoms), plus at least two molecules of ammonium nitrate (to provide the two NH2 (amine) groups above. You’ll also want at least 2 molecules of NaOH to have enough Na to react with the nitrate groups of the ammonium nitrate. As a first guess, assume that all atoms are the same size. A better way to do this involves molecular weights (formula weights), read a chemistry book, or look on the internet.

Four more experiments can be seen here. This post was getting to be over-long.As with this experiment, wear gloves and eye protection; don’t drink the chemicals, and if you get any chemicals on you, wash them off quick.

Here are a few more experiments in electrochemistry and biology, perhaps I’ll add more. In the meantime, if you or your child are interested in science, I’d suggest you read science books by Mr Wizard, or Isaac Asimov, and that you learn math. Another thought, take out a high school chemistry text-book at the library — preferably an old one with experiments..

Robert Buxbaum, December 29, 2013. If you are interested in weather flow, by the way, here is a bit on why tornadoes and hurricanes lift stuff up, and on how/ why they form. 

My failed process for wood to green gasoline

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Most researchers publish the results of their successful projects, and ignore the rest. It’s an understandable failing given the cost and work to publish and the general sense that the project that flops indicated a loser – researcher. Still, it’s a shame, and I’d like to break from it here to describe a worthwhile project of mine that failed — turning wood into green gasoline. You may come to believe the project worthwhile too, and figure that you might learn from my story some pathways to avoid if you decide to try it. Besides I figure that it’s an interesting tale. All success stories are similar, I find; failure can come in many ways.

Failure can come from incorrect thinking – assumptions that are wrong. One basis of my thinking was the observation that gasoline, for the most part, was crude-oil that had been fluffed up with hydrogen. The density you buy weighs about 5.5 lb/gallon while crude oil weighs 9 lb/gallon. The difference is hydrogen. Perhaps wood too could be turned into gasoline if hydrogen were added. Another insight was that the structure of wood was the structure of a long chain -alcohol,  —(CHOH)-(CHOH)-(CHOH)—. My company had long experience breaking alcohols to make hydrogen. I figured we could do something similar with wood, fluffing up the wood by breaking the long-chain alcohols to short ones.

A possible first reaction step would be to break a C-O-C bond, a ketone bond, with hydrogen:

—(CHOH)-(CH2O)-(CHOH)— + H2 –>  —(CHOH)-CH2OH + CH2OH—

The next reaction step, I imagined was de-oxygenation:

—(CHOH)-CH2OH  +  H2 –>  —(CHOH)-CH3  + H2O

At this point, we are well on the way to making gasoline, or making a gasoline-relevant alcohol like C6H11-OH. The reactions I wanted were exothermic, meaning they would probably “go” — in actuality -∆G is the determinate of reaction favorability, but usually a -∆H and -∆G go together. Of course there are other reactions that I could have worried about –Ones that produce nasty goop. Among these:

–(CHOH)-(CH2O)-(CHOH)—  –> –(CO)-(C)-(CHOH)— + H2O +H2

I didn’t worry about these reactions because I figured I could outrun them using the right combination of a high hydrogen pressure, the right (low) temperature and the right catalyst. I may have been wrong. Then again, perhaps I picked the wrong catalyst – Fe2O3/ rust, or the wrong set of conditions. I picked Fe2O3 because it was cheap and active.

I convinced myself that Fe2O3 was sufficiently specific to get the product to a good 5-6 carbon compounds for gasoline. Wood celluloses are composed of five and six-carbon ring structure, and the cost of wood is very low per energy. What could go wrong? I figured that starting with these 5-6 carbon ring structures, virtually guaranteed getting high octane products. With the low cost and all the heat energy of the wood, wood + H2 seemed like a winning way to store and transport energy. If i got 6 carbon alcohols and similar compounds they’d have high-octane and the right vapor pressures and the products should be soluble in ordinary gasoline.

And the price was right; gasoline was about $3.50/ gallon, while wood was essentially free.  Hydrogen isn’t that expensive, even using electrolysis, and membrane reactors (a major product of our company) had the potential to make it cheaper. Wood + Hydrogen seemed like the cheaper version of syngas: CO +H2, and rust is similar to normal Fischer Tropsch catalyst. My costs would be low, and I’d expected to get better conversion since I should get fewer low molecular weight products like methane, ethane and methanol. Everything fundamental looked like it was in my favor.

With all the fundamentals in place, I figured my only problem would be to design a reasonably cheap reactor. At first I considered a fluidized bed reactor, but decided on a packed bed reactor instead, 8″ long by 3/4″ OD. This was a tube, filled with wood chips and iron oxide as a catalyst. I introduced high pressure hydrogen via a 150 psi hydrogen + 5% He mix. I hoped to see gasoline and water come out the other end. (I had the hydrogen – helium mix left over from a previous experiment, and was paying rental; otherwise I would have used pure hydrogen). I used heat tape and a controller to keep the temperature near-constant.

Controlling the temperature was key, I thought, to my aim of avoiding dehydration and the formation of new carbon-carbon bonds. At too high a temperature, the cellulose molecules would combine and lose water to form a brown high molecular weight tar called bio-oil, as well as methane and char. Bio-oil is formed the same way you form caramel from sugar, and as with sugar, it’s nothing you’d want to put in a car. If I operated at too low a temperature (or with the wrong catalyst) the reaction would be too slow, and the capital costs would be excessive. I could keep the temperature in the right (Goldilocks) temperature, I thought with the right catalyst and the right (high) hydrogen pressure.

No matter how I did this, I knew that I’d get some carbon-carbon bond formation, and perhaps a little char, but so long as it wasn’t too much it should be manageable. I figured I could hydrogenate the tar and remove the char at the end of the process. Most of the gasoline energy would come from the trees, and not the hydrogen, and there would be little hydrogen wasted forming methane. Trees would always be cheap: they grow quickly, and are great at capturing solar energy. Many cities pay for disposal of their tree waste, so perhaps a city would pay us to take their wood chips. With cheap wood, the economics would be good so long as used all the hydrogen I put in, and got some reasonable fraction of energy from the wood. 

i began my reaction at 150°C with 50 psi hydrogen. At these conditions, I saw no reaction; I then raised the temperature to 200°C, then raised the pressure to 100 psi (still nothing) and then tried 250°C, still at 100psi. By now we were producing water but it was impossible to tell if we were hydrogenating the cellulose to gasoline, or dehydrating the cellulose to bio-oil.

As it turned out we were getting something worse that bio-oil: bio-oil gunk. Instead of the nasty brown liquid that’s made when wood is cooked to dehydration (water removal, caramelization), I got something that was nastier than I’d imagined possible. The wood molecules did not form nice chains but combined to form acidic, aromatic gunk (aromatic in both senses: benzine-type molecules and smelly) that still contained unreacted wood as a sort of press-board. The gunk was corrosive and reactive; it probably contained phenol, and seemed bent on reacting to form a phenolic glue. I found the gunk was insoluble in most everything: water, gasoline, oil, methanol (the only exception was ethanol). As best I can tell, you can not react this gunk with hydrogen to make gasoline as it is non-volatile, and almost impossible to get out of my clogged reactor. Perhaps a fluidized bed would be would be better, but I’m afraid it would form wood clumps even there. 

I plan to try again, perhaps using higher pressure hydrogen and perhaps a liquid hydrogen carrier, to get the hydrogen to the core of the wood and speed the catalysis of the desired products. The key is finding a carrier that is not too expensive or that can be easily recovered.

Robert E. Buxbaum, Dec 13, 2013. Here’s something on a visit to my lab, on adding hydrogen to automobile engines, and on the right way to do science. And here’s my calculation for how much wood a woodchuck chucks if a woodchuck could chuck wood, (100 lbs/ night) plus why woodchucks do not chuck wood like beavers.

Thermodynamics of hydrogen generation

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Perhaps the simplest way to make hydrogen is by electrolysis: you run some current through water with a little sulfuric acid or KOH added, and for every two electrons transferred, you get a molecule of hydrogen from one electrode and half a molecule of oxygen from the other.

2 OH- –> 2e- + 1/2 O2 +H2O

2H2O + 2e- –>  H2 + 2OH-

The ratio between amps, seconds and mols of electrons (or hydrogen) is called the Faraday constant, F = 96500; 96500 amp-seconds transfers a mol of electrons. For hydrogen production, you need 2 mols of electrons for each mol of hydrogen, n= 2, so

it = 2F where and i is the current in amps, and t is the time in seconds and n is the number electrons per molecule of desired product. For hydrogen, t = 96500*2/i; in general, t = Fn/i.

96500 is a large number, and it takes a fair amount of time to make any substantial amount of hydrogen by electrolysis. At 1 amp, it takes 96500*2 = 193000 seconds, 2 days, to generate one mol of hydrogen (that’s 2 grams H2 or 22.4 liters, enough to fill a garment bag). We can reduce the time by using a higher current, but there are limits. At 25 amps, the maximum current of you can carry with house wiring it takes 2.14 hours to generate 2 grams. (You’ll have to rectify your electricity to DC or you’ll get a nasty H2 /O2 mix called Brown’s gas, While normal H2 isn’t that dangerous, Browns gas is a mix of H2 and O2 and is quite explosive. Here’s an essay I wrote on separating Browns gas).

Electrolysis takes a fair amount of electric energy too; the minimum energy needed to make hydrogen at a given temperature and pressure is called the reversible energy, or the Gibbs free energy ∆G of the reaction. ∆G = ∆H -T∆S, that is, ∆G equals the heat of hydrogen production ∆H – minus an entropy effect, T∆S. Since energy is the product of voltage current and time, Vit = ∆G, where ∆G is the Gibbs free energy measured in Joules and V,i, and t are measured Volts, Amps, and seconds respectively.

Since it = nF, we can rewrite the relationship as: V =∆G/nF for a process that has no energy losses, a reversible process. This is the form found in most thermodynamics textbooks; the value of V calculated this way is the minimum voltage to generate hydrogen, and the maximum voltage you could get in a fuel cell putting water back together.

To calculate this voltage, and the power requirements to make hydrogen, we use the Gibbs free energy for water formation found in Wikipedia, copied below (in my day, we used the CRC Handbook of Chemistry and Physics or a table in out P-chem book). You’ll notice that there are two different values for ∆G depending on whether the water is a gas or a liquid, and you’ll notice a small zero at the upper right (∆G°). This shows that the values are for an imaginary standard state: 20°C and 1 atm pressure. You can’t get 1 atm steam at 20°C, it’s an extrapolation; behavior at typical temperatures, 40°C and above is similar but not identical. I’ll leave it to a reader to send this voltage as a comment.

Liquid H2O formation∆G° =-237.14
Gaseous H2O formation∆G° =-228.61

The reversible voltage for creating liquid water in a reversible fuel cell is found to be -237,140/(2 x 96,500) = -1.23V. We find that 1.23 Volts is about the minimum voltage you need to do electrolysis at 0°C because you need liquid water to carry the current; -1.18 V is about the maximum voltage you can get in a fuel cell because they operate at higher temperature with oxygen pressures significantly below 1 atm. (typically). The minus sign is kept for accounting; it differentiates the power out case (fuel cells) from power in (electrolysis). It is typical to find that fuel cells operate at lower voltages, between about .5V and 1.0V depending on the fuel cell and the power load.

Most electrolysis is done at voltages above about 1.48 V. Just as fuel cells always give off heat (they are exothermic), electrolysis will absorb heat if run reversibly. That is, electrolysis can act as a refrigerator if run reversibly. but electrolysis is not a very good refrigerator (the refrigerator ability is tied up in the entropy term mentioned above). To do electrolysis at reasonably fast rates, people give up on refrigeration (sucking heat from the environment) and provide all the entropy needed for electrolysis in the electricity they supply. This is to say, they operate at V’ were nFV’ ≥ ∆H, the enthalpy of water formation. Since ∆H is greater than ∆G, V’ the voltage for electrolysis is higher than V. Based on the enthalpy of liquid water formation,  −285.8 kJ/mol we find V’ = 1.48 V at zero degrees. The figure below shows that, for any reasonably fast rate of hydrogen production, operation must be at 1.48V or above.

Electrolyzer performance; C-Pt catalyst on a thin, nafion membrane

Electrolyzer performance; C-Pt catalyst on a thin, nafion membrane

If you figure out the energy that this voltage and amperage represents (shown below) you’re likely to come to a conclusion I came to several years ago: that it’s far better to generate large amounts of hydrogen chemically, ideally from membrane reactors like my company makes.

The electric power to make each 2 grams of hydrogen at 1.5 volts is 1.5 V x 193000 Amp-s = 289,500 J = .080 kWh’s, or 0.9¢ at current rates, but filling a car takes 20 kg, or 10,000 times as much. That’s 800 kW-hr, or $90 at current rates. The electricity is twice as expensive as current gasoline and the infrastructure cost is staggering too: a station that fuels ten cars per hour would require 8 MW, far more power than any normal distributor could provide.

By contrast, methanol costs about 2/3 as much as gasoline, and it’s easy to deliver many giga-joules of methanol energy to a gas station by truck. Our company’s membrane reactor hydrogen generators would convert methanol-water to hydrogen efficiently by the reaction CH3OH + H2O –> 3H2 + CO2. This is not to say that electrolysis isn’t worthwhile for lower demand applications: see, e.g.: gas chromatography, and electric generator cooling. Here’s how membrane reactors work.

R. E. Buxbaum July 1, 2013; Those who want to show off, should post the temperature and pressure corrections to my calculations for the reversible voltage of typical fuel cells and electrolysis.

Another Quantum Joke, and Schrödinger’s waves derived

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Quantum mechanics joke. from xkcd.

Quantum mechanics joke. from xkcd.

Is funny because … it’s is a double entente on the words grain (as in grainy) and waves, as in Schrödinger waves or “amber waves of grain” in the song America (Oh Beautiful). In Schrödinger’s view of the quantum world everything seems to exist or move as a wave until you observe it, and then it always becomes a particle. The math to solve for the energy of things is simple, and thus the equation is useful, but it’s hard to understand why,  e.g. when you solve for the behavior of a particle (atom) in a double slit experiment you have to imagine that the particle behaves as an insubstantial wave traveling though both slits until it’s observed. And only then behaves as a completely solid particle.

Math equations can always be rewritten, though, and science works in the language of math. The different forms appear to have different meaning but they don’t since they have the same practical predictions. Because of this freedom of meaning (and some other things) science is the opposite of religion. Other mathematical formalisms for quantum mechanics may be more comforting, or less, but most avoid the wave-particle duality.

The first formalism was Heisenberg’s uncertainty. At the end of this post, I show that it is identical mathematically to Schrödinger’s wave view. Heisenberg’s version showed up in two quantum jokes that I explained (beat into the ground), one about a lightbulb  and one about Heisenberg in a car (also explains why water is wet or why hydrogen diffuses through metals so quickly).

Yet another quantum formalism involves Feynman’s little diagrams. One assumes that matter follows every possible path (the multiple universe view) and that time should go backwards. As a result, we expect that antimatter apples should fall up. Experiments are underway at CERN to test if they do fall up, and by next year we should finally know if they do. Even if anti-apples don’t fall up, that won’t mean this formalism is wrong, BTW: all identical math forms are identical, and we don’t understand gravity well in any of them.

Yet another identical formalism (my favorite) involves imagining that matter has a real and an imaginary part. In this formalism, the components move independently by diffusion, and as a result look like waves: exp (-it) = cost t + i sin t. You can’t observe the two parts independently though, only the following product of the real and imaginary part: (the real + imaginary part) x (the real – imaginary part). Slightly different math, same results, different ways of thinking of things.

Because of quantum mechanics, hydrogen diffuses very quickly in metals: in some metals quicker than most anything in water. This is the basis of REB Research metal membrane hydrogen purifiers and also causes hydrogen embrittlement (explained, perhaps in some later post). All other elements go through metals much slower than hydrogen allowing us to make hydrogen purifiers that are effectively 100% selective. Our membranes also separate different hydrogen isotopes from each other by quantum effects (big things tunnel slower). Among the uses for our hydrogen filters is for gas chromatography, dynamo cooling, and to reduce the likelihood of nuclear accidents.

Dr. Robert E. Buxbaum, June 18, 2013.

To see Schrödinger’s wave equation derived from Heisenberg for non-changing (time independent) items, go here and note that, for a standing wave there is a vibration in time, though no net change. Start with a version of Heisenberg uncertainty: h =  λp where the uncertainty in length = wavelength = λ and the uncertainty in momentum = momentum = p. The kinetic energy, KE = 1/2 p2/m, and KE+U(x) =E where E is the total energy of the particle or atom, and U(x) is the potential energy, some function of position only. Thus, p = √2m(E-PE). Assume that the particle can be described by a standing wave with a physical description, ψ, and an imaginary vibration you can’t ever see, exp(-iωt). And assume this time and space are completely separable — an OK assumption if you ignore gravity and if your potential fields move slowly relative to the speed of light. Now read the section, follow the derivation, and go through the worked problems. Most useful applications of QM can be derived using this time-independent version of Schrödinger’s wave equation.

My steam-operated, high pressure pump

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Here’s a miniature version of a duplex pump that we made 2-3 years ago at REB Research as a way to pump fuel into hydrogen generators for use with fuel cells. The design is from the 1800s. It was used on tank locomotives and steamboats to pump water into the boiler using only the pressure in the boiler itself. This seems like magic, but isn’t. There is no rotation, but linear motion in a steam piston of larger diameter pushes a liquid pump piston with a smaller diameter. Each piston travels the same distance, but there is more volume in the steam cylinder. The work from the steam piston is greater: W = ∫PdV; energy is conserved, and the liquid is pumped to higher pressure than the driving steam (neat!).

The following is a still photo. Click on the YouTube link to see the steam pump in action. It has over 4000 views!

Mini duplex pump. Provides high pressure water from steam power. Amini version of a classic of the 1800s Coffee cup and pen shown for scale.

Mini duplex pump. Provides high pressure water from steam power. A mini version of a classic of the 1800s Coffee cup and pen shown for scale.

You can get the bronze casting and the plans for this pump from Stanley co (England). Any talented machinist should be able to do the rest. I hired an Amish craftsman in Ohio. Maurice Perlman did the final fit work in our shop.

Our standard line of hydrogen generators still use electricity to pump the methanol-water. Even our latest generators are meant for nom-mobile applications where electricity is awfully convenient and cheap. This pump was intended for a future customer who would need to generate hydrogen to make electricity for remote and mobile applications. Even our non-mobile hydrogen is a better way to power cars than batteries, but making it mobile has advantages. Another advance would be to heat the reactors by burning the waste gas (I’ve been working on that too, and have filed a patent). Sometimes you have to build things ahead of finding a customer — and this pump was awfully cool.