Utilization of Captured CO2 for Conversion to Alkyl Carbonates

C.B. Panchal, J.C. Prindle, R. Sturtz, R. Doctor
E3Tec Service, LLC,
United States

Keywords: CO2 utilization, alkyl carbonates, heat integrated reactive distillation


There are very limited uses of captured CO2 other than for enhanced oil recovery (EOR) which currently has in excess of 126 projects globally; some as high as a 2 Mtonne/yr capacity. The Global Carbon Capture and Sequestration (CCS) Insititute provides a list of current and future storage sites and also highlights the challenges and costs of coordinating the development of a CO2 transportation infrastructure. Few major industrial CO2 generation sources (e.g. refineries, petrochemical production, ammonia/urea manufacturing facilities, fossil power generation plants etc.) are located close to these storage sites. As a result, different technologies for conversion of captured CO2 to value-added products are being actively pursued. E3Tec is pursuing SBIR project aimed at utilization of captured CO2 from utility and industrial plants for manufacturing of dimethyl carbonate (DMC) with selective co-production of mono-ethylene glycol (MEG). DMC is a high-value specialty chemical with major applications in manufacturing polycarbonate, as low VOC solvent, in lithium-ion batteries and as an intermediate in manufacturing of polyurethane. DMC is also evaluated as fuel additive for diesel that will expand the DMC market tremendously requiring new plants. MEG is a major commodity chemical used in polyethylene terephthalate (PET) with end-use in making films, fibers and bottles. The project team acknowledges that not a single chemical product would be able to make a major impact CO2 abatement, either by direct consumption and/or off-setting CO2 emission for the end product. However, multiple plants from distributed CO2 source sites will make significant dent into the overall CO2 abatement target. In order to make a major impact of CO2 utilization for chemical production on large scale, commodity chemicals such as methanol and urea; however, it would be very hard to compete in commodity chemicals, especially with low natural gas prices. Specialty chemicals, such as DMC and MEG, with favorable product margin will provide the basis for early commercialization. Furthermore, methanol is feedstock for DMC, so once the DMC technology demonstrated, an integrated process of CO2 capture, methanol and DMC can be developed. In essence, DMC is an ideal chemical for utilization of CO2.