Research is active on the design and synthesis of a new carbon dioxide (CO2) capture solvent based on PEG-Siloxane. Unlike conventional gas-removal solvents, the NETL’s new solvent technology is hydrophobic and has a low vapor pressure. A hydrophobic solvent with low vapor pressure is highly advantageous because it can reduce the cost and energy-consumption associated with CO2 capture by simplifying solvent regeneration and negating the need to remove water from fuel gas. For example, this solvent operates above room temperature and can be regenerated using low-grade and waste heat, whereas commercially available solvents operate below room temperature and can’t be regenerated using low-grade or waste heat This technology is available for licensing and/or further collaborative research from the U.S. Department of Energy’s National Energy Technology Laboratory.
Unlike pre-combustion CO2 capture technologies currently employed at integrated gasification combined cycle (IGCC) systems, NETL’s PEG-Siloxane-based solvent is hydrophobic and has a low vapor pressure. Traditional solvents must operate at below room temperature, which requires the use of a chiller, and rely on a pressure-swing process to be regenerated. Both of these processes consume electricity, whereas the NETL patented solvent can operate at above room temperature and can be regenerated using waste/low-grade heat. This can result in a savings of approximately 50 MW at a 500 MW IGCC-CCS power plant.
Traditional carbon capture solvents may also suffer from foaming, which can significantly reduce the mass transfer of CO2 into the solvent because foaming requires that the absorber be operated at lower gas flow velocities. The novel NETL solvent reduces the tendency to foam under these conditions, which may help to keep capital costs for the absorber to a minimum.
Pre-combustion CO2 separation and capture at IGCC-CCS
Generation of H2 from reformed natural gas or from syngas
Adjustment of CO/H2 ratio for Coal and Biomass to Liquids
Removal CO2 from syngas for Coal and Biomass to Ammonia/Fertilizer
Natural gas sweetening
Storage of light gases (carbon dioxide, methane, hydrogen, hydrogen sulfide)
U.S. Patent No: 10,589,228
Title: Di-Substituted Siloxane Solvents for Gas Capture
Inventors: David P. Hopkinson, Nicholas Siefert, Robert L. Thompson, Megan Macala, Lei Hong
NETL Reference No: 17N-14