Nees Marthe, Adeel Muhammad, Pazdur Lukasz, Porters Matthew, Vande Velde Christophe M L, Billen Pieter
Intelligence in Processes, Advanced Catalysts and Solvents (iPRACS), Faculty of Applied Engineering, University of Antwerp, Groenenborgerlaan 171, Antwerp 2020, Belgium.
BlueChem, Triple Helix, Olieweg 95, Antwerpen 2020, Belgium.
ACS Omega. 2024 Oct 16;9(43):43438-43446. doi: 10.1021/acsomega.4c04671. eCollection 2024 Oct 29.
The alcoholysis of polyurethane waste is currently being industrialized, making it one of the most advanced chemical recycling processes for polyurethanes. However, the recycling potential of the dicarbamate phase, which accounts for 10-40% of the polyurethane mass, is often disregarded, as mainly the polyol components are (partially) retrieved in many alcoholysis processes. In this study, we present a two-step recycling method in which the valuable carbamate fraction obtained in the initial alcoholysis step is transformed into an isocyanate-rich mixture through an additional thermolysis step. For this purpose, different carbamates were synthesized and thermolyzed, which showed that thermolysis with isopropyl-carbamate was the most favorable, obtaining a yield of 35%. As a result, the isocyanates obtained through thermolysis and the polyols obtained through alcoholysis can be reused as starting materials in polyurethane synthesis.
聚氨酯废料的醇解目前正在工业化，使其成为最先进的聚氨酯化学回收工艺之一。然而，占聚氨酯质量10%-40%的二氨基甲酸酯相的回收潜力常常被忽视，因为在许多醇解工艺中主要是（部分）回收多元醇成分。在本研究中，我们提出了一种两步回收方法，其中在初始醇解步骤中获得的有价值的氨基甲酸酯馏分通过额外的热解步骤转化为富含异氰酸酯的混合物。为此，合成并热解了不同的氨基甲酸酯，结果表明用异丙基氨基甲酸酯进行热解最为有利，产率为35%。因此，通过热解获得的异氰酸酯和通过醇解获得的多元醇可作为聚氨酯合成的起始原料重新使用。
