PEP Review 2009-2
Asahi Kasei Diphenyl Carbonate Process Involving the Production and Use of Dibutyl Carbonate
Published: June 2009
A series of recent published patents and patent applications assigned to Asahi Kasei describes an innovative process for indirectly producing diphenyl carbonate (DPC) from carbon dioxide and phenol. The process involves first the production of di-n-butyl carbonate (DBC) from n-butanol and carbon dioxide mediated by organotin complexes. The DBC is then reacted with phenol under reaction distillation conditions to produce DPC and n-butanol which is recycled to DBC production. This Review provides detailed descriptions and interpretations of the patent information, creation of a conceptual process flow scheme, results of a process simulation of the scheme, and development of capital and production cost estimates for a 90,000 MTA plant. The estimated transfer price for the DPC is about $1.20/lb, a value that is significantly higher than other reported transfer price values for DPC produced using alternative dimethyl carbonate based methodologies.