Tag Archives: REB Research

New REB hydrogen generator for car fueling, etc.

One of my favorite invention ideas, one that I’ve tried to get the DoE to fund, is a membrane hydrogen generator where the waste gas is burnt to heat the reactor. The result should be exceptional efficiency, low-cost, low pollution, and less infrastructure needs. Having failed to interest the government, I’ve gone and built one on my own dime. That’s me on the left, with Shua Spirka, holding the new core module (reactor, boiler, purifier and purifier) sized for personal car fueling.

Me and Shua and our new hydrogen generator core

Me and Shua and our new hydrogen generator core

The core just arrived from the shop last week, now we have to pumps and heat exchangers. As with our current products, the hydrogen is generated from methanol water, and extracted 99.99999% pure by diffusion through a metal membrane. This core fit in a heat transfer pot (see lower right) and the pot sits on a burner for the waste gas. Control is tricky, but I think I’ve got it. If it all works like it’s supposed to, the combination should be 80-90% energy-efficient, delivering about 75 slpm, 9 kg per day. That’s the same output as our largest current electrically heated generators, with a much lower infrastructure cost. The output should be enough to fuel one hydrogen-powered automobile per day, or keep a small fleet of plug-in, hydrogen-hybrids running continuously.

Hydrogen automobiles have a lot of advantages over Tesla-type electric automobiles. I’ll tell you how the thing works as soon as we set it up and test it. Right now, we’ve got other customers and other products to make.

Robert Buxbaum, February 18, 2016. If someone could supply a good hydrogen compressor, and a good fuel cell, that would be most welcome. Someone who can supply that will be able to ride in a really excellent cart of the future at this year’s July 4th parade.

Air swimmer at REB Research

Birds got to swim and fish got to fly. Gonna love that hydrogen till the day I die. Here’s a movie of our hydrogen-filled air swimmer, a fish-blimp at REB Research. My hope is that this thing will help us sell hydrogen generators — perhaps to folks who fly military balloons, or those who fly hydrogen balloons for sport. On the other hand, the swimmer is a lot of fun to play with — and I got to show it off to a first grade class!

Aside from balloon fliers, military and otherwise, the sort of customers I’d hoped to attract were those building fueling stations for fuel cell cars or drone airplanes, and those running multiple gas chromatographs or adding hydrogen to car or diesel engine. Even small amounts of hydrogen added to a standard engine will reduce pollution significantly, add raise mileage too: a plus for a company like VW.

Dr. Robert E. Buxbaum, December 2, 2015. I should mention that hydrogen balloons are no where near as unsafe as people think. Here’s a movie I made of lighting a hydrogen filled balloon with a cigar.

I make weapons too, but they don’t work

My company, REB Research, makes items with mostly peaceful uses: hydrogen purifiers and hydrogen generators — used to make silicon chips and to power fuel cells. Still, several of our products have advanced military uses, and these happen to be our most profitable items. The most problematic of these is the core for a hydrogen-powered airplane designed to stay up forever. An airplane like this could be used for peace, e.g. as a cheap, permanent cell tower, or for finding shipwrecks in the middle of the ocean. But it could also be used for spying on US citizens. Ideally I’d like to see my stuff used for desirable ends, but know it’s not always that way.

See, no matter how many times I pull the trigger the damn thing just won't fire! Gahan Wilson;

See what I mean? No matter how many times I pull the trigger the damned thing just won’t fire! Gahan Wilson;

I’d be less bothered if I had more faith that my government will only spy on bad guys, but I don’t. Our politicians seem focused on staying in office, and most presidents of the 20th century have kept enemies lists of those who they’d like to get back at — politics isn’t pretty. I’d be more picky if I could figure out how to sell more stuff, but so far I have not. I thus need the work. I take a sort-of comfort, however, in the fact that the advanced nature of the technology means that my customers keep having troubles getting things to work. My parts work, but the plane has yet to fly as intended. Perhaps, by the time they do get it flying, spying may have changed enough that my stuff will be used only for beneficial service to mankind, or as a stepping stone to more general use. Hydrogen as a fuel makes a lot of sense, especially for airplanes.

Robert E. Buxbaum, June 15, 2015. Here’s a description of my membrane reactors, and a description of my latest fuel cell reformer idea. There are basically two types of engineer; those who make weapons and those who make targets. I make the case here that you want to make targets. Some weapons have only one short day in the sun, e.g. the Gatling gun.

Thermodynamics of hydrogen generation

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 Hor 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 every losses, the 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: 0°C and 1 atm pressure. You can’t get 1 atm steam at 0°C, it’s an extrapolation; room temperature behavior is pretty similar (i.e: there’s a non- negligible correction that I’ll leave to a reader to send 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).

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 it is not a very good refrigerator (the refrigerator ability is tied up in the entropy term mentioned above). To do electrolysis at fast rates, people give up on refrigeration and provide all the energy needed in the electricity. In this case, ∆H = nFV’ where ∆H is the enthalpy of water formation, and V’ is this higher voltage for electrolysis. Based on the enthalpy of liquid water formation,  −285.8 kJ/mol we find V’ = 1.48 V at zero degrees. At this voltage no net heat is given off or absorbed. The figure below shows that you can use less voltage, but not if you want to make hydrogen fast:

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.

What’s Holding Gilroy on the Roof

We recently put a sculpture on our roof: Gilroy, or “Mr Hydrogen.” It’s a larger version of a creepy face sculpture I’d made some moths ago. Like it, and my saber-toothed tiger, the eyes follow you. A worry about this version: is there enough keeping it from blowing down on the cars? Anyone who puts up a large structure must address this worry, but I’m a professional engineer with a PhD from Princeton, so my answer is a bit different from most.

Gilroy (Mr Hydrogen) sculpture on roof of REB Research & Consulting. The eyes follow you.

Gilroy (Mr Hydrogen) sculpture on roof of REB Research & Consulting. The eyes follow you. Aim is that it should withstand 50 mph winds.

The main force on most any structure is the wind (the pyramids are classic exceptions). Wind force is generally proportional to the exposed area and to the wind-speed squared: something called form-drag or quadratic drag. Since force is related to wind-speed, I start with some good statistics for wind speed, shown in the figure below for Detroit where we are.

The highest Detroit wind speeds are typically only 16 mph, but every few years the winds are seen to reach 23 mph. These are low relative to many locations: Detroit has does not get hurricanes and rarely gets tornadoes. Despite this, I’ve decided to brace the sculpture to withstand winds of 50 mph, or 22.3 m/s. On the unlikely chance there is a tornado, I figure there would be so much other flotsam that I would not have to answer about losing my head. (For why Detroit does not get hurricanes or tornadoes, see here. If you want to know why tornadoes lift things, see here).

The maximum area Gilroy presents is 1.5 m2. The wind force is calculated by multiplying this area by the kinetic energy loss per second 1/2ρv2, times a form factor.  F= (Area)*ƒ* 1/2ρv2, where ρ is the density of air, 1.29Kg/m3, and v is velocity, 22.3 m/s. The form factor, ƒ, is about 1.25 for this shape: ƒ is found to be 1.15 for a flat plane, and 1.1 to 1.3 a rough sphere or ski-jumper. F = 1.5*1.25* (1/2 *1.29*22.32) = 603 Nt = 134 lb.; pressure is this divided by area. Since the weight is only about 40 lbs, I find I have to tie down the sculpture. I’ve done that with a 150 lb rope, tying it to a steel vent pipe.

Wind speed for Detroit month by month. Used to calculate the force. From http://weatherspark.com/averages/30042/Detroit-Michigan-United-States

Wind speed for Detroit month by month. Used to calculate the force. From http://weatherspark.com/averages/30042/Detroit-Michigan-United-States

It is possible that there’s a viscous lift force too, but it is likely to be small given the blunt shape and the flow Reynolds number: 3190. There is also the worry that Gilroy might fall apart from vibration. Gilroy is made of 3/4″ plywood, treated for outdoor use and then painted, but the plywood is held together with 25 steel screws 4″ long x 1/4″ OD. Screws like this will easily hold 134 lbs of steady wind force, but a vibrating wind will cause fatigue in the metal (bend a wire often enough and it falls apart). I figure I can leave Gilroy up for a year or so without worry, but will then go up to replace the screws and check if I have to bring him/ it down.

In the meantime, I’ll want to add a sign under the sculpture: “REB Research, home of Mr Hydrogen” I want to keep things surreal, but want to be safe and make sales.

by Robert E. Buxbaum, June 21, 2013

New hydrogen generator from REB Research

Here’s the new, latest version of our Me150 hydrogen generator with our wonder-secretary, Libby, shown for scale. It’s smaller and prettier than the previous version shown at left (previous version of Me150, not of secretary). Hydrogen output is 99.9999% pure, 9.5 kg/day, 75 slpm, 150 scfh H2; it generates hydrogen from methanol reforming in a membrane reactor. Pricing is $150,000. Uses about 7 gal of methanol-water ($6 worth) per kg of H2 (380 ft3). Can be used to fill weather balloons, cool electric dynamos, or provide hydrogen fuel for 2-10 fuel cell cars.

New REB Research hydrogen generator 150 scfh of 99.9999% H2 from methanol reforming

New REB Research hydrogen generator 150 scfh of 99.9999% pure H2 from methanol-water reforming against metal membranes.

Dr. Robert E. Buxbaum

Some people have noticed that I’m wearing a rather dapper suit during the recent visit of the press to my lab. It’s important to dress sharp, I think, and that varies from situation to situation. Fashion is an obligation, not a privilege; you’ve got to be willing to suffer for it, for the greater good of all.

Do you think Lady Gaga finds her stuff comfortable?

Do you think Lady Gaga finds her stuff comfortable? She does it for the greater good. 

R.E. Buxbaum. You are your own sculpture; Be art.

 

Robert Buxbaum is now on the board of a new charity

I’m now on the board of directors for two non-profits (lucky me), plus for my own hydrogen company, REB Research. My first charity seat is for The Jewish Heritage Foundation; it’s really one rabbi who takes donations to make tapes about topics he finds interesting. He then gives away or sells the tapes. We meet once a year to go over the finances and decide what his salary ought to be — basically we rubber stamp.

The second board seat, one I’ve been elected/appointed to just this week, is with a group call “The First Covenant Foundation” they’re semi-religious, trying to get people to behave decently. The first covenant is the one with Noah — God won’t destroy the earth but we have to behave sort-of OK. It’s certainly worthwhile to get people to keep to this minimal standard: no murder, no bestiality, don’t eat the limbs off of living creatures… Then again, if God has trouble keeping folks to this standard, I’m not sure how effective the 1st covenant will be. So far they’ve done nothing illegal or immoral that I’ve seen, so that’s good. Unlike with my first my board position, my contract with first covenant includes a sanity clause. They’re more inclusive that way; as expected, the Jewish heritage group didn’t believe in any sanity clause.

As for REB Research, our aims are simpler: to make and sell good hydrogen-related products, to make money, to pay our workers and creditors, and to develop our workers through training associated with the making and selling of good hydrogen products. Simple enough. My board meets 3 or 4 times a year over pizza; the salary of board members is the pizza. So far we haven’t done anything illegal either, that I know of — and we’re even making money.

A visit to the Buxbaum laboratory from Metromedia

It’s a slow news day in Detroit, so the folks from Metromedia came to visit my laboratory at REB Research. You can visit too. We’re doing cool stuff most of the time, we’re working on a hydrogen-fueled plane that stays aloft for weeks (not that cool, actually, the Hindenberg did it in the 30s). On this particular day I’ve got a cool hat on, and a beige suit. I’m putting hydrogen in my car. Hydrogen increases the speed of combustion, and so it adds to milage — or it has when we’ve added it from electrolysis sources.buxbaum-003

The fun thing about science is that there are always surprises.

Adding hydrogen to a Malibu at REB Research

Adding hydrogen to a Malibu at REB Research

REB Research periodic table cup

Some 20 years ago I designed this periodic table cup, but with only the 103 named elements that existed then. In part this was done because I wanted a good, large, white coffee cup, in part because I often found I needed a periodic table, and didn’t like to have to look one up, and in part to people how much more area you get on a cylinder than on a flat sheet (roughly 3.14 times more area). To show that, I put all the side elements (rare earth lanthanides, and actinides) where they belonged, and not off on the side. I also put hydrogen in twice, once as a metal (HCl) and once as a non metal (NaH). The color I chose was Tryian Blue, a key color of Biblical Tyre, what you get from male purpura mollusks (the females give a shade of red that I also try to associate with REB Research).

I’ve updated the cup to add more elements: I think it’s great. You can buy it for $30 through our web-site, or for $25 by e-mailing me (reb@rebresearch.com). Or if you do something really cool, I may send you one for free.

REB Research, Periodic table coffee cup

REB Research, Periodic table coffee cup

By the way, I only use 4 digits for the atomic weight; I can think of no application where a normal person needs more.