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This paper focuses on the world’s first non-phosgene process using CO2 as starting material succeeded in development and industrialization by Asahi Kasei Corp. The Asahi Kasei Process enables high-yield production of high-quality PC having excellent properties and high-purity monoethylene glycol (MEG), starting from ethylene oxide (EO), by-produced CO2 and bisphenol-A without waste and waste water. The innovative reactive distillation technologies in the monomer production and the innovative gravity-utilized, non-agitation polymerization reactor in the melt polymerization, led the new process to success. The monomer process consists of 3 production steps, ethylene carbonate (EC) from CO2 and EO, dimethyl carbonate (DMC) and MEG from EC and MeOH, and diphenyl carbonate (DPC) and MeOH from DMC and PhOH. All intermediates are recycled. The new type polymerization reactor perfectly overcomes the difficulty based on the extremely high viscosity in the melt polymerization of DPC with Bis-A. The by-produced PhOH is recycled to the monomer process. The reduction of CO2 emissions (0.173t/PC 1t) is also achieved, because CO2 used as raw material is utilized as the main chain components of the products. Four commercial plants (Taiwan: 150,000 t/y, Korea: 2 plants of 65,000 t/y, Russia: 65,000 t/y) using the Asahi Kasei Process are now successfully operating, and the plant of 260,000 t/y in Saudi Arabia will start in 2010.

Asahi Kasei Corp. has succeeded in the development of a new green process for producing an aromatic polycarbonate based on bisphenol-A (hereafter usually abbreviated as PC) without using phosgene and methylene chloride. The new PC production process is the world's first to use carbon dioxide (CO2) as a starting material. Until Asahi Kasei's new process was revealed, all of the PC in the world has been produced using carbon monoxide (CO) made from cokes or lower hydrocarbons and oxygen as a starting material. Furthermore, more than about 93% of the PC has been produced by the so-called “phosgene process” which uses phosgene made from CO and chlorine (Cl2) as a monomer. However, the phosgene process inherently involves a number of environmental and economic shortcomings in addition to the high toxicity of phosgene itself and the high carcinogenic probability of methylene chloride itself. Asahi Kasei's new process enables high-yield production of the two important products for our citizens’ lives, high-quality PC and high-purity monoethylene glycol (MEG), starting from ethylene oxide (EO), carbon dioxide (CO2) and bisphenol-A. This new technology not only overcomes the environmental and economic problems existing in the phosgene process, but also achieves resource conservation, and energy conservation. Furthermore, the new process contributes to the earth environment by the reduction of CO2 emissions (173 tons per thousand tons of product PC). Commercial application of the new process was carried out at the 50,000 ton year−1 PC plant of Chimei-Asahi Corporation, a joint venture between Asahi Kasei Corporation and Chi Mei Corporation, which was newly constructed in Taiwan and has been successfully operating since June 2002. In recognition of the outstanding advance in ecological and sustainable performance that this technology represents, Japan's Minister of Economy, Trade and Industry conferred the Green and Sustainable Chemistry Award of 2003 on us. Furthermore, the Chairman of Japan Chemical Industry Association also conferred the 35th Japan Chemical Industry Association Award of 2003 on us as an outstanding chemical technology. An outline of this new non-phosgene PC process embodying the spirit of Green and Sustainable Chemistry is given here.