Conversion of CO2 to Alkyl Carbonates using Ethylene Oxide as Feedstock

Statement of Problem: Globally, there is urgent need for technologies for managing CO2 captured from industrial sources with no suitable geological reservoirs nearby. Three basic sources of CO2 are: a) hydrogen production using Steam-Methane Reforming - SMR; b) combustion of Natural Gas (NG) for power generation using Gas Turbine Combined Cycle (GTCC); and 3) FutureGen - oxyfuel coal combustion. Capturing and purifying CO2 and then sequestration is a costly; therefore, new generation of cost-effective technologies are needed for conversion of CO2 to high-value products with expanding market for making a substantial impact on management of CO2. Technical Objectives: The governing Phase I objective is to establish, via life-cycle analysis (LCA) of the carbon footprint, the techno-economic viability of converting CO2 from three primary CO2 sources to dimethyl carbonate (DMC) and ethylene glycol (EG) using E3Tecs process of heat integrated reactive distillation (HIRD). Technical Approach: The proposed SBIR project will develop the technology to the commercialization stage for conversion of CO2 captured from industrial exhaust sources to high-value industrial chemicals. In this process, methanol and ethylene oxide are secondary feedstocks for co-production of the high-value products dimethyl carbonate (DMC) and ethylene glycol (EG) from CO2. The expected outcomes of the Phase I project are: a) identification of the techno-economic merits of the proposed process based on validated ASPENPlus process analysis; and b) development of a commercialization strategy with the focus on a modular commercial plant having positive cash flow within 5 years after completing Phase II. Commercial Applications and Other Benefits: The numerous uses for DMC make it an ideal candidate for consumption of captured CO2. The major applications of DMC are: a) production of polycarbonate resins; b) solvent with low VOC; c) potential use in Lithium-Ion betteries; and d) candidate as oxygenated fuel additive in diesel. DMC in the U.S. is primarily manufactured (one million metric tonnes per year) using an old phosgene (highly toxic chemical) based process. Successful development of the proposed HIRD process with small C-footprint will replace this phosgene based process. Key Words: CO2 conversion, value-added products, alkyl carbonates, ethylene glycol, heat integrated reactive distillation, process intensification. Summary for Members of Congress: Globally industry is developing various technologies for converting captured carbon dioxide to high-value products as alternate to costly sequestration. Therefore, strong public-private partnerships are required for maintaining competitive edge of the U. S. industry for managing carbon dioxide domestically as well as competing for global market.