Issue 3, 2023

Detoxification of bisphenol A via sulfur-mediated carbon–carbon σ-bond scission

Abstract

Environmental contamination with bisphenol A (BPA), produced via degradation of plastic waste, constitutes a major hazard for human health due to the ability of BPA to bind to estrogen receptors and thereby induce hormonal imbalances. Unfortunately, BPA cannot be degraded to a “safe” material without breaking C–C σ-bonds, and existing methods required to break these bonds employ petroleum-derived chemicals and environmentally-harmful metal ions. Therefore, there is an urgent need to develop new “green” methods to break BPA into monoaryl compounds without the use of such reagents and, ideally, convert those monoaryls into valuable materials that can be productively utilized instead of being discarded as chemical waste. Herein we report a new mechanism by which O,O′-dimethyl bisphenol A (DMBPA), obtained from BPA-containing plastic via low-temperature recycling, undergoes C–C σ-bond cleavage via thiocracking, a reaction with elemental sulfur at temperatures lower than those used in many thermal plastic recycling techniques (e.g., <325 °C). Mechanistic analyses and microstructural characterization of the DMBPA-derived materials produced by thiocracking elucidated multiple subunits comprising monoaryl species. Impressively, analyses of recoverable organics revealed that >95% of DMBPA had been broken down into monoaryl components. Furthermore, the DMBPA–sulfur composite produced by thiocracking (BC90) exhibited compressive strength (∼20 MPa) greater than those of typical Portland cements. Consequently, this new thiocracking method creates the ability to destroy the estrogen receptor-binding components of BPA wastes using greener techniques and, simultaneously, to produce a mechanically-robust composite material that represents a sustainable alternative to Portland cements.

Graphical abstract: Detoxification of bisphenol A via sulfur-mediated carbon–carbon σ-bond scission

Supplementary files

Article information

Article type
Paper
Submitted
19 12 2022
Accepted
10 3 2023
First published
17 3 2023
This article is Open Access
Creative Commons BY license

RSC Sustain., 2023,1, 535-542

Detoxification of bisphenol A via sulfur-mediated carbon–carbon σ-bond scission

T. Thiounn, M. S. Karunarathna, M. K. Lauer, A. G. Tennyson and R. C. Smith, RSC Sustain., 2023, 1, 535 DOI: 10.1039/D2SU00138A

This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements