Patent ID: 7935736
Filing Date: 2011-05-03
Classification: B29B,B29K,B29L,C08J,Y02W

Abstract:
1. A method for recycling polyesters or polyester mixtures from polyester-containing waste, comprising: dissolving the polyester or polyester mixture in a solvent including one or more of dimethyl ester or diethyl ester of oxalic acid, maleic acid, succinic acid, glutaric acid, and adipinic acid; precipitating at least a portion of the polyester or at least a portion of the polyester mixture as free-flowing particles with a precipitant including one or more of non-polar substances, aliphatic hydrocarbons, and mixtures of petroleum, ether and benzenes, such that the precipitant mixes with the solution of the polyester or polyester mixture in a single phase; and cooling the polyester or polyester mixture, the precipitant, and/or the solvent to a temperature of 60° C. to 120° C., such that the precipitant and the solvent separate into two liquid phases, wherein the two phases are separated mechanically and can be re-used for the method.