Journal of Chemical Engineering & Process Technology
Open Access

Abstract

Sustainability and Economic Analysis of Propylene Carbonate and Polypropylene Carbonate Production Processes Using CO2 and Propylene Oxide

Yasar Demirel

Currently, the industrially important polycarbonates are synthesized from bisphenol A and diphenyl carbonate, which are highly toxic and hence other feasible alternatives are preferable. Following the considerable advances on the catalyst for the synthesis of carbonates from CO2 and propylene oxide (PO), industrial scale processes for the productions of propylene carbonate (PC) and polypropylene carbonate (PPC) have been designed and simulated with sustainability and economic analyses. The CO2 is supplied by a nearby bioethanol plant, while the PO from a petrochemical process. The first part of the study is for the production of 200 million lb/year cyclic PC by using 9990 lb/ hr of CO2. Ionic liquid-1-n-ethyl-3-methylimidazolium chloride is used as a catalyst. The net CO2 emission reduction is around −0.318 lb CO2/lb PC, while the net cost of duty (heating+cooling) is around $1.92×10−3/lb PC. The second part is for the production of 261 million lb/year PPC by using 14523.2 lb/hr CO2. The process uses (salen) CrIIICl complex as catalyst. The net CO2 emission reduction is around −0.342 lb CO2/lb PPC, while the net cost of duty/lb PPC is around $7.978×10−3/lb PPC. Economic analyses show that the feasibility of the both production plants depends on the selling price of PC and PPC. Both the production plants for PC and PPC are sustainable as they use CO2 and avoid toxic feedstock. Beside the engineering economics, a focused sustainability analysis should also be considered in the feasibility evaluation of chemical process technologies.