Abstract: A method of depolymerization of waste polymer material into monomers comprises releasing at least part of the at least one dye from the waste polymer material in an alcoholic solvent without depolymerizing the condensation polymer in the waste polymer material and at conditions preventing a reaction between the dye and the alcoholic solvent, wherein the alcoholic solvent is a polyol. The alcoholic solvent is added in a weight ratio of the alcoholic solvent to the waste polymer material of between 200:1 and 10:1. The at least partially decolorized waste polymer is then separated from the alcoholic solvent, and the at least one dye is extracted from the alcoholic solvent so as to regenerate the alcoholic solvent, which is led to a storage for reuse. The condensation polymer is depolymerized in the purified recovered alcoholic solvent by using a catalyst. A reactor system for carrying out the method is also described.

Abstract: The invention relates to a solid composition comprising at least 90.0 wt. % bis(2-hydroxyethyl) terephthalate (BHET), as based on dry weight and having a pore volume in the range of 0.20 to 1.0 cm3/g. The porosity is above 25% or even above 35%. The solid composition is made by crystallisation, followed by granulation and fluid bed drying.