Optimization of Bisphenol S And F Photodegradation by Titanium Dioxide Under UVA Irradiation

Abstract

Toxic chemicals present in plastic additives leach into the aqueous environment, leading to concerns regarding their adverse effects.3 One such additive, bisphenol A (BPA), commonly used in plastic manufacturing has been banned by several countries, including Malaysia.4 Bisphenol S (BPS) and bisphenol F (BPF) have emerged as substitutes for BPA and are frequently detected in environmental samples that can be detrimental to all life forms.1, 2 This study investigated the effectiveness of titanium dioxide to completely photodegrade BPS and BPF in aqueous solution under UVA irradiation. Several photodegradation parameters, including the initial pH of the solution, photocatalyst dosage, and illumination period, were optimized. Upon optimization, at the initial concentration of 5 mg/mL, 100% of BPS and 99.6% of BPF were photodegraded within 180 minutes and 240 minutes, respectively, under UVA irradiation. The adsorption capability of titanium dioxide for BPS and BPF was explored based on Langmuir and Freundlich isotherm models. Based on the results, BPS fitted well with Langmuir isotherm while BPF had a higher correlation of determination for Freundlich isotherm. The maximum adsorption capacities obtained for BPS and BPF based on the Langmuir isotherm were 20.08 mg/g and 20.70 mg/g, respectively. Furthermore, the Langmuir constant related to the affinity of binding sites showed that titanium dioxide has a higher affinity for BPF. The experimental results demonstrated that titanium dioxide in the presence of UVA irradiation can effectively photodegrade BPS and BPF present in an aqueous solution.