Gas-to-Liquids Process for Monetization of CO₂-Rich Gas

Gas-to-liquids (GTL) technology, i.e., the catalytic conversion of synthesis gas (primarily hydrogen and carbon monoxide) derived from natural gas, coal, petroleum coke, and/or biomass, to liquid hydrocarbons, has been utilized since the early 20^th century to produce liquid fuels and chemicals. Since World War II, the U.S. Bureau of Mines, and thereafter the U.S. Department of Energy ("DOE"), sponsored numerous research and development programs in the GTL area with the ultimate objective of employing the technology domestically in order to increase U.S. energy independence and security. However, GTL technology is currently only economically viable at large scales, such that more than 60% of the world's natural gas fields cannot likely be economically exploited with existing process designs. Therefore, there is a need to develop new GTL process technology that permits the monetization of small natural gas fields (< 1 trillion cubic feet), including landfill gas fields (<< 1 trillion cubic feet).

While employed at CeraMem Corporation, Dr. Bradford, through collaboration with Advanced Hydrocarbon Systems, LLC (Acton, MA), developed a novel GTL process design for the monetization of landfill gas that is applicable in general to the conversion of CO₂-rich natural gas. CeraMem Corporation released all information related to this GTL process design to |i²| Systems, which has since improved the process design and economics. Preliminary process designs for 2 BPD and 260 BPD pilot plants are available.

For more information, download our disclosure.
 

Selective Hydrocarbon Conversion to Acetylene

In the first half of the 20^th century, many valuable chemical intermediates (such as vinyl acetate) were produced using acetylene, the demand for which could grow appreciably if technical hurdles related to the commercialization of high-conductivity polyacetylene-based materials are overcome. In addition, there is growing domestic and global demand for acetylene as a fuel for welding applications.

Approximately 68% of U.S. acetylene production capacity is based on natural gas pyrolysis or partial oxidation, 18% is derived from ethylene co-production, and 14% is obtained via calcium carbide hydrolysis. However, each of these technologies has distinct disadvantages. For example, arc and plasma-based routes to natural gas conversion have intrinsically high electrical costs. Pyrolysis-based processes generate dilute concentrations of acetylene and ethylene in the reactor effluent, thus necessitating energy-intensive and expensive downstream separation steps. Product yields are lower than the theoretical limits because intrinsic chemical kinetics and thermodynamic equilibrium generate a broad product distribution, in part because ethylene and acetylene can rapidly oligomerize to aromatics and decompose to coke at the elevated temperatures employed by these technologies. In addition, calcium carbide-based processes are capital and energy intensive. Consequently, there is a need for an efficient process that selectively produces acetylene at moderate conditions.

While employed at CeraMem Corporation, Dr. Bradford, through collaboration with Advanced Hydrocarbon Systems, LLC (Acton, MA), developed an advanced, multi-step process that employs tailored and regenerable intermediates for the selective conversion of natural gas, or any other low-value gaseous hydrocarbon stream, to acetylene. This technology concept has since been released to |i²| Systems. Preliminary process designs are available for production capacities of 2 and 20 metric tons of acetylene per day.

For more information, download our disclosure.
 

cis-Δ⁹-Desaturation of Fatty Acid Alkyl Esters

The choice of appropriate technologies for the manufacture of crude biodiesel from vegetable oil and animal fat depends on several factors, such as the feedstock FFA (Free Fatty Acid) and MIU (Moisture, Impurities, and Unsaponified) contents, which vary widely. If the feedstock FFA content is less than 5%, technologies such as solvent extraction and caustic stripping can be used to further reduce feedstock FFA content, so that purified triglycerides can be subsequently reacted with an alcohol and a base catalyst via transesterification to produce crude biodiesel and glycerine. Alternatively, feedstocks with higher FFA contents can be hydrolyzed to yield a purified FFA stream that is subsequently reacted with an alcohol and an acid catalyst via esterification to produce crude biodiesel.

The composition of the crude biodiesel obtained in these processes depends strongly on the feedstock composition, and the overall performance of biodiesel as a fuel depends upon its composition. Although the biodiesel might ideally contain ³96 wt% of cis-mono-unsaturated alkyl esters, biodiesel derived from soy, yellow grease, lard and tallow contains appreciable quantities of saturated alkyl esters, such as palmitic acid alkyl ester (C16:0) and stearic acid alkyl ester (C18:0). In this regard, biodiesel with an excessive content of saturated fatty acid alkyl esters can be upgraded via development of a selective, catalytic, oxidative dehydrogenation/desaturation technology.

While employed at CeraMem Corporation, Dr. Bradford, conceived of an advanced technology for the selective cis-Δ⁹-desaturation of fatty acid alkyl esters that is applicable to upgrading biodiesel, as well as other chemical transformations in the oleo-chemical industry. The technology concept has been released to |i²| Systems.

For more information, download our disclosure.
 

Advanced Inorganic Membrane for Hydrogen Separation

"The coupled challenges of a doubling in the world's energy needs by the year 2050 and the increasing demands for 'clean' energy sources that do not add more CO₂ and other pollutants to the environment have resulted in increased attention worldwide to the possibilities of a 'H₂ economy' as a long-term solution for a secure energy future."¹ "Hydrogen can be produced from coal, natural gas, biomass, and biomass derivatives through the use of gasification, pyrolysis, reforming, and shift technologies. In all cases, a hydrogen-rich producer gas or syngas results, from which the hydrogen must be separated and purified. The most common approach today involves the use of pressure swing adsorption technology. However, the use of membranes holds the promise of reducing costs by combining the separation and purification with the shift reaction in a reactive separation operation. Membranes of interest include ceramic ionic transport membranes, micro-porous membranes, and palladium based membranes."² However, the membranes currently developed or under development in academic, government, and industrial laboratories each have limitations that prevent or restrict their applicability to hydrogen separation and production from synthesis gas derived from the gasification of coal and biomass.

|i²| Systems has identified a novel class of inorganic, microporous materials that could be ideal for use in the fabrication of ceramic membranes for hydrogen separation that heretofore has neither been proposed nor investigated for said purpose.

For more information, download a non-confidential version of our 2005 DOE I&I pre-proposal.

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¹ "Basic Research Needs for the Hydrogen Economy: Report of the Basic Energy Sciences Workshop on Hydrogen Production, Storage, and Use, 13-15 May 2003," DOE Office of Science. http://www.sc.doe.gov/bes/hydrogen.pdf.

² Department of Energy, Small Business Innovation Research FY2005 Solicitation, Topic 19c.