Industrial & Engineering Chemistry Research, Vol.46, No.25, 8687-8692, 2007
Economic and environmental impact analyses of catalytic olefin hydroformylation in CO2-expanded liquid (CXL) media
Recently, CEBC researchers reported a new hydroformylation process concept that uses CO2-expanded liquids (CXLs) as reaction media. The hydroformylation turnover frequencies (TOFs) were up to 4-fold higher in CXLs than those in neat organic solvent. The enhanced rates were achieved at milder conditions (30-60 degrees C. and 4-12 MPa) compared to industrial processes (140-200 degrees C and 5-30 MPa). Preliminary economic and environmental analyses of the CXL process are presented here and benchmarked against a simulated conventional hydroformylation process for which nonproprietary data were obtained mostly from the Exxon process. The simulation results indicate that the CXL process has clear potential to be economically viable and environmentally favorable subject to nearly quantitative recovery and recycle of the rhodium-based catalysts. For the simulated conventional process, acetic acid discharged during the catalyst recovery steps is the dominant source of adverse environmental impact. These analyses have provided guidance in catalyst design and in choosing materials and operating conditions that favor process economics while lessening environmental footprint.