Depolymerization of Flexible Polyurethane Foam Waste Via “Split Phase” Glycolysis Using Zinc Acetate [Zn(Ac)2] for Ultimate Recovery of Polyol
No Thumbnail Available
Date
2017-10
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Addis Ababa University
Abstract
Polyurethanes find wider range of application, in many industrial sectors. This results generation of bulk of waste which affects the environment in many aspects of pollution. Amongst many techniques, chemical recycling is most preferred to carry out the recycling of PU waste scrap because of its ability to yield recycled polyol that can be used as an alternative to the virgin polyol. For this study one of chemical recycling approach, which is glycolysis specifically “split phase glycolysis” was chosen as a method that allows recovering a polyol with related quality and property of the virgin polyol. The recovery process goes through on by using ethylene glycol as a solvent and zinc acetate Zn (Ac)2 as a catalyst by considering parameters like, temperature, catalyst loading and decomposition time. Then, two phases are obtained: an upper phase which contains the recovered polyol and, a bottom phase which includes sub-products of the reaction with the excess of glycol. Finally, properties such us hydroxyl value, viscosity, amine value, acid value and water content of the recovered polyol were analyzed in considering of “ASTDM” and compared with that of virgin polyol. Based on that hydroxyl value of (144.3mg KOH/g), viscosity of (276.208cps), total amine value (10.878mg KOH/g), then moisture content (1.74%) and acid value of (0.012mg KOH/g); at a temperature 190 0c, catalyst load of 2% and reaction time of 2hr were found as best result of the recovered polyol properties lied under the standard range of virgin polyol.
Keywords: Chemical Recycling, Glycolysis, Polyurethane, Polyol
Description
Keywords
Chemical Recycling, Glycolysis, Polyurethane, Polyol