Recovery of polyols from flexible polyurethane foam by “split-phase” glycolysis: Study on the influence of reaction parameters

The general purpose of polyurethane chemical recycling is to recover constituent polyol, a valuable raw material. Among suitable processes, glycolysis, especially in two phases, allows better quality products. Potassium octoate a compound derived from cycloaliphatic carboxylic acids shows suitable catalytic activity.A detailed study of the main reaction parameters affecting the reaction and properties of the recovered polyol has been carried out. They include carboxylate catalyst concentration, reaction temperature and mass ratio of treated foam to the glycolysis agent.An increase in the reaction temperature and catalyst concentration enhances the degradation rate, however, it also affects the process negatively by promotion of secondary reactions and contamination of the polyol phase. Related to the glycolysis agent amount, the minimum quantity required to split the phases has been determined, as well as the optimal ratio.