Removal of bisphenol A from wastewater by physical, chemical and biological remediation techniques. A review

Bisphenol A is a well-known endocrine-disrupting compound that is commonly detected in industrial effluents and wastewater treatment plants. It is extensively used in the production of polycarbonate and epoxy resins. It is linked to serious environmental pollution and negative effects in humans and living microorganisms, i.e., malfunction of the endocrine system through imitating or blocking natural hormones. Several bisphenol A remediation techniques have been investigated over the last decades, with many of them gradually emerging as effective ones. This article summarizes the most recent findings and progress of the highly effective and widely accepted bisphenol A elimination/degradation techniques, such as membrane separation, adsorption, advanced oxidation processes, and biodegradation, based on their beneficial and optimistic aspects, namely, ease of operation, excellent bisphenol A removal performance, and cost-effectiveness. The operational specifications affecting the elimination efficiency and concerning mechanisms of the processes are summarized. The prominent remarks from this article are as follows. (i) Reverse osmosis, membrane distillation, and nanofiltration-based membrane separation processes particularly eliminated similar to 100% of bisphenol A from the contaminated aqueous solutions; however, the durability and force resistance frame integrity of the membranes need to be increased. Combining the membrane separation techniques with other oxidation/biodegradation techniques can lower the major issues of each technique; i.e., integrating the membrane separation and electrochemical oxidation can reduce the fouling and mass transfer limitation issues of both the techniques, respectively. (ii) Numerous conventional and nonconventional adsorbents can effectively eliminate bisphenol A from effluents; however, the higher adsorbability and rapid adsorption rates need to be addressed. (iii) Mono/bimetal ion-loaded catalysts could significantly degrade bisphenol A via photocatalysis; however, variation in reaction rates, catalyst deactivation owing to fouling, complex structures, intricate fabrication methods, and uncontrollable morphology of metal-based nanocatalysts remain the core issues. (iv) Numerous bacterial species/fungi/fungal enzymes and microalgae can effectively biodegrade bisphenol A with comparatively higher efficiencies. Finally, prominent remarks and perspectives from this paper provide perception and future investigation directions to address existing problems of bisphenol A-contaminated wastewater treatment.