Using ionic liquid catalyst for conversion of waste polyethylene terephthalate and soybean oil to polyester polyol

Abstract

International audienceAn imidazolium ionic liquid was synthesized, characterized and used as a catalyst for conversion of polyethylene terephthalate (PET) and soybean oil to polyester polyol (PE polyol). The degradation of PET waste was carried out using glycerol and low cost soybean oil that resulted in the formation of PE polyols. Formed PE polyols were characterized using Fourier transform infrared (FT-IR) and mass spectra method, thermo gravimetric and differential thermal analysis and gel permeation chromatoghraphy. The first step in the overall process is proposed to be the transesterification of soybean oil with glycerol to form monoglyceride or/and diglyceride of soybean oil fatty acids. In the second step, the obtained glycerides can react with PET to form PE polyol. Both steps could be combined in one process and acidic catalyzed by an ionic liquid. Ionic liquid can be used as active catalyst and show a high reusability. The influence of some factors such as amount of glycerol used in transesterification of soybean oil with glycerol, PET degradation time, and temperature on PET conversion were investigated to find the suitable conditions for the process. Under suggested optimum parameters (mass ratio of soybean oil to glycerol of 2:1, a time of 8 h and a temperature of 180 °C for PET degradation), a PET conversion of 87.3% was reache

Mechanistic Insights of Cosolvent Efficient Enhancement of PET Methanol Alcohololysis

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“…16−18 Among all chemical methods, alcoholysis is the most widely used, mainly including glycolysis, 19−21 methanol alcoholysis, 22 isooctanol alcoholysis, 23 and polyol alcoholysis. 24 Compared with other alcoholysis reactions, the methanol alcoholysis method can avoid colored impurities in the degradation products and facilitate the efficient separation and purification of the products. And the demand for dimethyl terephthalate (DMT), a product obtained from methanol degradation of PET, is gradually increasing; the product DMT can be more easily purified and used as a raw material for the subsequent synthesis of PET.…”

Effects of ionic liquids as catalysts on liquid crystal aromatic polyester based on thin‐film polymerization technique

“…ILs as catalysts have been extensively utilized to catalyze various reactions, such as hydrogenation, carbonylation and Friedel‐Crafts, due to the high reactivity, low toxicity, easy recycle and strong solubility 10–12 . In recent years, ILs have been employed to facilitate the transesterification reaction to prepare diversified products and polymers 13–16 . In particular, ILs as catalysts to prepare biodiesel through transesterification reaction have drawn extensive attention 15,17 .…”

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