Environmental Performance of Alternative Green Polyol Synthesis Routes: A Proposal for Improvement

Abstract

This study verified the environmental effectiveness of potentially less aggressive routes for the synthesis of poly(propylene/ethylene oxide) glycol (PPG). The analysis was developed in two stages. Firstly, the environmental performance of the conventional PPG processing route was compared to alternative variants—vegetal PPG and CO2-based PPG—applying the life cycle assessment technique to measure the primary energy demand, global warming potential, acidification, photochemical oxidation, and freshwater ecotoxicity impact categories. The synthesis of vegetable polyols from bio-based assets, such as vegetable oils, and the application of CO2 conversion routes as an alternative to technologies supported by petroleum and natural gas were studied. The use of CO2 recovered through carbon capture and usage practices resulted in environmental gains for PPG production. The processing routes within vegetal assets were not an environmentally attractive option as the performance was worse than the conventional arrangement by 144% for the global warming impact category, an increase related to the deforestation carried out to expand soybean cultivation in Brazil. Secondly, improvement scenarios to mitigate the environmental impacts of alternative routes were performed. The hypothesis of using cleaner inputs to obtain a more ecofriendly route was tested. The analysis concluded that the use of high-purity CO2 brings fewer benefits compared to other capturing sources that need a purification process before feeding the PPG synthesis.

Ex-ante life cycle assessment of polyols using carbon captured from industrial process gas

“…Several LCA studies have been published on CCU technologies used for the production of chemicals, 9,10 most of which were focused on the production of polyols from CO 2 . 11–14 However, to the best of our knowledge, there have been no LCA studies carried out for the joint production of both CO-based polyols and CO 2 -based polyols from the CO and CO 2 fractions of BFG.…”

Enhanced Double Metal Cyanide Catalysts for Modulating the Rheological Properties of Poly(propylene carbonate) Polyols by Modifying Carbonate Contents

“…Polyols, which contain two or more hydroxyl groups per molecule, are crucial to the production of polyurethane (PU) products, including flexible and rigid foams, coatings, adhesives, sealants, and elastomers. , Depending on their specific application, they can be classified into polyether, polyester, and polycarbonate (PC) polyols. PC and poly­(propylene carbonate) (PPC) polyols are produced through the copolymerization of epoxides and CO 2 using different catalysts such as Co­(III) complexes, Cr­(III) complexes, or Lewis acids for the former and double metal cyanide (DMC) catalysts for the latter .…”

Catalytic epoxidation of palm oleic acid by heterogeneous catalysts: Optimization and kinetic model

“…This cyclic ether contains a three‐atom ring, in which two of the atoms are carbon atoms of a hydrocarbon and are attached to an oxygen atom 3 . The most researched bio‐based resource for the creation of sustainable polyols is undoubtedly vegetable oils 4 . It is significant to note that these studies implicitly acknowledged that improving the environmental sustainability of epoxides and produced polymer synthesis may be achieved by replacing all or even a portion of petrochemical assets with bio‐based resources.…”