H2 from Multiple Fuels & Polymeric Membrane Separation

So much is going on in hydrogen these days, but one still wonders whether truly novel developments will ultimately be the key to making H2 an economic and practical part of the energy system. H2fuel, a small technology development company in Chicago, has two important innovations that may be examples the kinds of breakthroughs that are needed.

1. Fuel Processor — Simpler cheaper integrated autothermal reformer system–sulfur tolerant

2. Polymeric Membrane — A unique new membrane that removes CO2 and H2S, by a chemical mass transport, not physical separation, while reducing CO.

H2fuel is jointly owned by Avista Labs(70%) and Unitel Fuel Technologies (30%). H2fuel is looking for investors. A business plan is available.

Lee Camara, Unitel, 847-297-2265
Mike Davis, Avista Labs, 509-228-6685

Here are some technical details, adapted from a 4-page summary the company has prepared, complete with color graphics. (download – password required):

Fuel Processor

A couple of years ago, H2fuel took over funding of work at Argonne on an autothermal reformer (ATR), and introduced new sulfur-tolerant catalysts. A key goal was to process any number of standard (sulfur bearing) fuels in the same device. The system now promises low cost, simple operation, ease of manufacture, rapid cycling (load following), and ease of manufacture.

Sulfur-tolerant water gas shift (WGS) catalysts have been qualified for both medium temperature and low temperature applications. One of the most significant breakthroughs is the elimination of the zinc oxide bed, thus allowing the H2S produced in this processor to go right through the reactor without any deleterious effects. The H2S is continuously removed by a new subsystem downstream (see below).

The CO produced in the fuel processor, ~1%, depending on the fuel, acts as a PEM fuel cell poison because it affects the anode electrocatalyst. H2fuel has developed a unique method for reducing the CO level to below 10 ppm, thus eliminating this problem.

H2fuel’s new hydrogen processor, with its sulfur-tolerant autothermal and water gas shift catalysts, and without the need for a zinc oxide bed, has been tested continuously for over 2500 hours with natural gas containing ~20 ppm sulfur compounds. During this period, it has successfully completed several load-following tests and maintained an output gas composition (dry basis) of 45% H2, 15% CO2, 1% CO, 0.4% CH4, balance N2. This reactor continues to be tested; however, the fuel is being changed to regular gasoline, and later to fuel grade ethanol.

Polymeric Membrane

On a separate front, under the auspices of a R&D program originally started at the University of Kentucky, and now being continued at Ohio State University, H2fuel has a controlling position in the IP developing polymeric membrane products and support devices to facilitate the removal of H2S and CO2 from the reformate product streams. The key component of this membrane separator is a surface layer that reacts with H2S and CO2, but not with H2 and CO. The membrane transports the reaction products from one side of the membrane to the other by mass transport. The H2S and CO2 desorb on the other side and are swept away. The H2 and CO don’t react with the membrane and are retained on the reformate side. A second membrane stage incorporates a catalyst to deplete the remaining CO in the reformate to less than 10 ppm.

This membrane technology can be used as well to clean up H2 from other production processes. Some major fuel cell companies have made clear their interest once higher temperature operation of the membrane is accomplished.