INDUSTRIAL PROCESS FOR THE PRODUCTION OF A DIALKYL CARBONATE AND A DIOL, AND, DIALKYL CARBONATE

摘要

INDUSTRIAL PROCESS FOR THE PRODUCTION OF A DIALKYL CARBONATE AND A DIOL, AND, DIALKYL CARBONATE is an object of the present invention, when producing a dialkyl carbonate and a diol industrially in a large quantity (for example not less than 2 tons / h for dialkyl carbonate and not less than 1.3 tonnes / h for diol), through a reactive distillation system using cyclic carbonate and aliphatic monohydric alcohol as starting materials, continuously feeding the starting within a continuous multi-stage distillation column where a catalyst is present, and carrying out the reaction and distillation simultaneously on the column, provide a specific process that allows dialkyl carbonate and diol to be produced, each, with selectivity high and steadily high productivity over an extended period of time (for example, not less than 1000 hours, preferably not less than 3000 hours, m preferably not less than 5000 hours) and, furthermore, allows the dialkyl carbonate produced to be separated and purified in a stable manner over a prolonged period of time with high efficiency. It was found that by carrying out reactive distillation using a multi-stage continuous distillation column A, having a specified structure, and subjecting an AT column top component thus obtained to distillation separation using a continuous stage distillation column multiples B, having a specified structure, a high-purity dialkyl carbonate (for example not less than 97%, preferably not less than 99%, more preferably not less than 99.9%, even more preferably not less than 99.99 %) and a diol can be produced each with a high selectivity of not less than 95%, preferably not less than 97%, more preferably not less than 99%, on an industrial scale of not less than 2 tons / h, preferably not less than 3 tons / h, more preferably not less than 4 tons / h, for dialkyl carbonate, and not less than 1.3 tons / h, preferably not less than 1.95 tons / h, more preferably not less than 2.6 tonnes / h for diol, with a stable high yield over a prolonged period of time of not less than 1000 hours, preferably not less than 3000 hours, more preferably not less than 5000 hours, from one cyclic carbonate and an aliphatic monohydric alcohol.