According to the University of Oregon, “Reporting in a paper placed online ahead of publication in the Journal of the American Chemical Society, a team of four UO scientists describes the development of a cyclic amine borane-based platform called BN-methylcyclopentane. In addition to its temperature and stability properties, it also features hydrogen desorption, without any phase change, that is clean, fast and controllable. It uses readily available iron chloride as a catalyst for desorption, and allows for recycling of spent fuel into a charged state … The U.S. Department of Energy, which funded the research, is shooting to develop a viable liquid or solid carrier for hydrogen fuel by 2017. The new UO approach differs from many other technologies being studied in that it is liquid-based rather than solid, which, Liu says, would ease the possible transition from a gasoline to a hydrogen infrastructure.”

The part of the system that needs further development is a more robust regenerative mechanism for this liquid fuel. Professor of Chemistry Shih-Yuan Liu says that current and past chemical storage methods for hydrogen usually involve a solid state such as storing H2 in ammonia borane or metal hydrides.

Two of the advantages of using a liquid hydrogen carrier are portability and familiarity. Tanker trucks and pipelines already carry a vast amount of liquids, so distribution of a liquid hydrogen carrier would not be as large of a departure from the current norm as would be compressed hydrogen gas. In addition, consumers are already familiar with pumping liquid fuels and this process, too would be very familiar to most who try it.

Apparently a group of researchers at USC in California had the same thought when they, “…developed a stable and reusable ruthenium catalyst that can extract a record amount of hydrogen from AB but produces far fewer by-products poisonous to fuel cells.”

One of the advantages of using ammonia borane (H3NBH3) is that it is a hydrogen rich chemical compound that can easily be transported over long distances (not like compressed hydrogen gas). Another advantage is that once spend, ammonia borane can easily be recycled and packed with hydrogen molecules once again.

The ammonia borane can be used in liquid slurries which are easy to transport over long distances or create locally and transport only short distances. The catalyst that the scientists have developed can release the hydrogen from the ammonia borane under mild temperatures with the largest quantity to date.

If you’re a fan of using chemical carries particularly hydrogen slurries then keep your eyes on this one for future development.

In addition, some clean diesel manufacturers include an ammonia tank on the vehicle to clean the exhaust on the way out of the vehicle, reducing its emissions. A company called SilverEagles Energy believe they have come up with a better mousetrap (a method of producing fuel grade ammonia) with the help researchers at the Texas Tech Advanced Vehicle Engineering Laboratory.

SilverEagles Energy is looking for investors to pump $8 million into the company to help them develop their ammonia fuel onsite and on-demand product. What is unique to the SilverEagles Energy approach is the use of ammonia blends that could be used now to cut down on emissions using today’s cars and light pickup trucks.

According to Lubbock Online, “Now, most ammonia is synthesized by the Haber process, named for German scientist Fritz Haber, who developed the process in 1910. It was used for such things as bus fuel in Europe during World War II.

“Ammonia could be used now, instead of ethanol, as an “A-10 — “10 percent” — fuel additive in cars and trucks with no change at all in gas tanks or engines, said Fleming adding flexfuel vehicles could run now on an A-85 fuel blend if a different gas tank were used.

“Ammonia-powered engines would represent a radical departure from what’s under the hood of today’s vehicles. The engine would generate electricity to be sent to the wheels, similar to the propulsion system in today’s hybrids and electric vehicles, rather than using a drivetrain and transmission.
“Because the piston process creates its own electricity, there would be no need for an alternator to power lights and other items. Engines would be air-cooled, eliminating the radiator, as well, Maxwell said.”

So, there you have it, another outside-the-box idea that has the potential to work short-term and long-term as a solution towards lowering emissions while increasing independent from foreign fossil fuel sources. This one small step for mankind, in hindsight could be a major leap.

So, I wanted to ask Mr. Holbrook a few questions about how hydrogen-rich NH3 may be used in the future to solve our nation’s transportation, clean air and energy independence issues.

Q&A

HydroKevin (HK): The Holy Grail for hydrogen cars is to use H2 that has been created renewably. But, ammonia (NH3) can also be created renewably, correct?

John Holbrook (JH): Yes, of course, NH3 can be produced renewably. The venerable Haber-Bosch (H-B) process, with its H2 for the reaction 3H2 + N2 –> 2NH3 derived from a non-fossil hydrogen source is one way. Usually the hydrogen source is water. Another method, recently patented, is Solid State Ammonia Synthesis (SSAS) where the SSAS reactor takes water directly to produce NH3. With SSAS, as with H-B, the nitrogen comes from air. Another patented, renewable method of producing NH3 uses biomass as input. One planned biomass for this process is spent corn cobs.

HK: What type of ammonia is most suitable to use as fuel for vehicles with internal combustion engines?

JH: The only ammonia form that can be used as a fuel is pure anhydrous ammonia, NH3. NH3 can be used directly in a spark ignited engine, and can be used to supply as much as 95-percent of the energy for a diesel engine. Other forms of ammonia, e.g. aqueous ammonia or urea cannot be used directly as a fuel and must have the NH3 separated from the water or CO2 and water, respectively. There is some recent work looking at anhydrous ammonia and NH3 salt blends. Those blends have also been shown to be satisfactorily combustible in internal combustion engines.

HK: Do you consider ammonia-powered cars to be hydrogen cars?

JH: Yes and no, I guess. A lot of us in the NH3 Fuel Association think and talk of NH3 being “the other hydrogen” because all the chemical energy in NH3 is delivered by burning/oxidizing the hydrogen in the NH3. But, we are not talking about only using NH3 as hydrogen carrier, where H2 would be liberated by thermo-catalytically cracking NH3, although it is quite possible and efficient to do that, i.e. store H2 in dense, liquid NH3. We also look at NH3 as a direct fuel. For instance, NH3 can be used directly as a fuel in engines, gensets, combustion turbines and direct-NH3 fuel cells.

HK: How can NH3 be used in conjunction with fuel cells?

JH: NH3 has a problem with low temperature PEM fuel cells because the PEM membrane can be destroyed by even low levels of NH3. That has not prevented some companies from successfully using cracked NH3 with PEM fuel cells. Also, there are at least two types of NH3 fuel cells that use un-cracked NH3 directly.

Many thanks to Mr. Holbrook and his insight into how ammonia may one day be created in mass quantities locally powering future vehicles cleanly so that we call can breathe a little easier.

Take for instance the researchers at the University of Alabama who have teamed up with scientists at the Los Alamos National Laboratory to develop ammonia borane for the transportation industry. The ammonia borane would be placed into a car, the hydrogen extracted, then run through a fuel cell along with ambient oxygen to create electricity to propel the vehicle.

Once the ammonia borane fuel has been spent, it will need to be recharged with hydrogen and this is just what the researchers have been working on. They have developed a way to recharge the spent fuel with hydrogen using “a single reactor.”

Meanwhile at Purdue University, researchers have discovered a way to use ammonia borane marbles that contain hydrogen and release it on demand. The initial use will have military applications for soldiers in the field using soda can size ammonia borane batteries rather than regular batteries.

The advantage is that ammonia borane weighs less, lasts longer and can be easily recharged. According to Purdue University, “The chemical compound, which is a derivative of ammonia borane, contains many hydrogen molecules locked into a safe, compact and highly portable material.”

Even though the research and development was originally commissioned for use by soldiers to run communications equipment and other electronics in the field, the researchers also believe their discovery can one day be used in fuel cell vehicles as well.

Now, a company called Cella Energy is using ammonia borane (NH3BH3) plus a process called coaxial electrospinning or electrospraying to either supply pure hydrogen to fuel cell vehicles or ICE cars that can run on H2 or to reduce emissions on fossil fuel based vehicles.

According to Cella, “The coaxial electrospinning process that Cella uses is simple and industrially scalable, it can be used to create micron scale micro-fibres or micro-beads nano-porous polymers filled with the chemical hydride. Cella believes that this technology can produce an inexpensive, compound material that be handled safely in air, operates at low pressures and temperatures and has sufficiently high hydrogen concentration and rapid desorption kinetics to be useful for transport applications.”

They go on to say, “Our current composite material uses ammonia borane NH3BH3 as the hydride and polystyrene as the polymer nano-scaffold. Ammonia borane in its normal state releases 12wt% of hydrogen at temperatures between 110°C and 150°C, but with very slow kinetics. In our materials the accessible hydrogen content is reduced to 6wt% but the temperature of operation is reduced so that it starts releasing hydrogen below 80°C and the kinetics are an order of magnitude faster.”

The hydrogen can also be used as a supplement to reduce current emissions in gasoline, diesel, JP-8, jet-fuel or kerosene. This can be done now using the current petroleum based refueling infrastructure with very little modifications.

The nano-scale beads that Cella refers to will move through the vehicle like a liquid, so it can be refueled as such as well. Once the hydrogen in the liquid is spent it can be pumped out of the vehicle and rehydrided somewhere else, recycled and used for fuel once again.

The elegance of this method is that thousands of high pressure hydrogen fueling stations will not need to be built to accommodate hydrogen cars. Slight modifications of current fueling stations will be needed only, so this solution could accelerate the introduction and acceptance of hydrogen cars on a wide scale very quickly. Cella, however is working on further improving its fuel so that widespread commercialization is possible.

A company called Linc Energy has discovered an Underground Coal Gasification (UCG) method that has been successfully trialed at their Chinchilla Demonstration Facility just outside of Queensland, Australia.

Linc Energy was able to use their proprietary method to reach coal seams underground that are too deep for traditional mining, meaning a new source of fuel is being tapped into. The result of UCG is called syngas (synthesis gas), which is composed mainly of hydrogen and carbon monoxide.

The carbon monoxide is then sequestered at the source and stored underground while the hydrogen is run through a fuel cell. In this case the hydrogen was run through an AFC Energy low-cost alkaline fuel cell which is 60-percent efficient in producing utility scale electricity compared to less than 40-percent at traditional coal-burning power plants.

Today, the most popular method for producing hydrogen is steam-reforming of natural gas, which also produces syngas. The hydrogen is separated and carbon sequestered and the hydrogen is used in the oil refinery business and in some in hydrogen cars.

The syngas used in the Linc Energy experiment is intended to be used for clean, hydrogen fueled power plants running off high temperature alkaline fuel cells. But, there is another market for this hydrogen as well including hydrogen cars.

Not all UCG mines will be located in places appropriate for power plants. In this case the hydrogen can be piped or trucked to fueling stations for use in cars. This also brings up the point that as the hydrogen economy revs up there will be more competition for this hydrogen among power plants that run off fuel cell or clean steam generators, stationary fuel cells for home and business and hydrogen cars.

This is one reason that more than one source for hydrogen fuel will be needed in the foreseeable future. We will need to produce hydrogen from coal, natural gas, water, ammonia and other hydrogen rich chemical compounds for some time to come.

The clean capture of the carbon and disposal of it may be trickier with some hydrogen production methods than with others. For instance, if we produce hydrogen from water using renewable resources such as wind and solar then we won’t have to worry about sequestering carbon. And this is the ideal.

But, to get the ball rolling in regard to producing hydrogen for cars and power plants we will need to use all available domestic resources to tide us over until renewable hydrogen fuel is able to take over the marketplace. And, this transition, like all large-scale disruptive technologies may take some time.

On of the disadvantages of using ammonia borane as a chemical carrier of hydrogen is that it takes significant energy to re-hydrogenate the spent chemicals. Researchers at the Los Alamos National Laboratory and University of Alabama are working on solving this issue.

Now, currently, researchers at Purdue University are using hydrothermolysis of ammonia borane (and water) to produce high yields of hydrogen. According to Purdue Professor Arvind Varma, “This is the first process to provide exceptionally high hydrogen yield values at near the fuel-cell operating temperatures without using a catalyst, making it promising for hydrogen-powered vehicles. We have a proof of concept.”

The new process will use waste heat from the fuel cells to separate the hydrogen from the ammonia borane in a reactor. This reactor will produce hydrogen at a safer compression (200 psi as opposed to 5,000 psi to 10,000 psi used in most current hydrogen vehicles).

The next step is for the researchers to scale up their design to work in a hydrogen fuel cell car and carry it at least 350 miles. Transporting an inert chemical compound such as ammonia borane will make a hydrogen refueling infrastructure much easier to build in comparison to using trucks with tanks of 10,000 psi or more on back (using the current gasoline infrastructure model).

So, you see, ammonia borane is not so boring after all.

Well, yes, I’m actually going to talk about algae one more time (now, there’s a surprise). Energy Quest in Henderson, Nevada is using its new PyStR (Pyrolysis Steam Reforming) process to create hydrogen from algae and other biomass.

The Pyrolysis process will not only create high purity hydrogen, but also high purity CO2 (carbon dioxide) and N2 (nitrogen) as well. Hydrogen can be sold on the open market for H2 cars and stationary fuel cells.

CO2 can also be sold on the open market for oil recovery from abandoned wells (where it can also be sequestered), carbonation for the beverage industry and as a feedstock to grow more algae. Nitrogen can be sold on the open market for the creation of ammonia for fertilizers, nitric acid or organic propellants.

Energy Quest is currently working with a manufacturer in Cleveland that is growing a strain of algae that requires more CO2 than is currently in the ambient air in order to hit its maximum growth rate.

Algae farming may likely become a growth industry in the future as all it needs to flourish is water, sunlight and CO2. Future Farmers of America may be growing algae instead of or in addition to corn, wheat, soybeans and other crops.

Organic fuel is nothing new and the fuel cell cars of the future may just powered by algae. Now, how green is that?

Ammonia borane as a solid is also easily transportable and would do away with the idea of transporting compressed H2 is large, long haul trucks.

The problem with using ammonia borane, however is that it takes significant energy to re-hydrogenate the chemicals that have been left behind. Now researchers at the Los Alamos National Laboratory and University of Alabama have made a discovery that uses less energy than previous methods to re-hydrogenate the chemicals back into ammonia borane.

The researchers discovered that by using a chemical called polyborazylene that ammonia borane could be easily recycled using a low amount of energy. The research team is using the assistance of Dow Chemical in scaling up this process for future commercial use.

Cheap manufacturing, storage and distribution of H2 has been the holdback of charging ahead with a hydrogen based transportation system (not the cars themselves). This new process of extracting hydrogen from ammonia borane and recycling it quickly and cheaply gives hope that a suitable infrastructure can be put in place faster most advocates and critics had previous prognosticated.