Bisphenol A (BPA) raises concerns among the scientific community as it is one of the most widely used compounds in industrial processes and a component of polycarbonate plastics and epoxy resins. In this review, we discuss the mechanism of BPA toxicity in food-grade plastics. Owing to its proliferation in the aqueous environment, we delved into the performance of various biological, physical, and chemical techniques for its remediation. Detailed mechanistic insights into these removal processes are provided. The toxic effects of BPA unravel as changes at the cellular level in the brain, which can result in learning difficulties, increased aggressiveness, hyperactivity, endocrine disorders, reduced fertility, and increased risk of dependence on illicit substances. Bacterial decomposition of BPA leads to new intermediates and products with lower toxicity. Processes such as membrane filtration, adsorption, coagulation, ozonation, and photocatalysis have also been shown to be efficient in aqueous-phase degradation. The breakdown mechanism of these processes is also discussed. The review demonstrates that high removal efficiency is usually achieved at the expense of high throughput. For the scalable application of BPA degradation technologies, removal efficiency needs to remain high at high throughput. We propose the need for process intensification using an integrated combination of these processes, which can solve multiple associated performance challenges.
In this study, novel lamellar double hydroxide composites (LDH-MgAl and LDH-MgFe) were synthesized at different metal salt ratios (1:1 to 3:1) and fully characterized using various techniques such as XRD, FTIR, SEM, EDS, and TGA. The resulting LDHs demonstrated a high affinity for efficiently removing tetracycline (TC) antibiotic from water, particularly at a moderate molar ratio of 3:1. This ratio exhibited improved structural characteristics, resulting in better TC uptake from water. The improved performance was supported by the increased abundance of surface functional groups (OH, NO3, CO32-, C-O-C, Fe-O, and Al-O-Al). The TGA analysis established the high stability of the LDHs when subjected to high temperatures. The kinetics of TC adsorption onto LDH fitted with the PSO (R2 = 0.935-0.994) and Avrami (R2 = 0.9528-0.9824) models, while the equilibrium data fitted the Liu and Langmuir isotherm models, with maximum monolayer adsorption capacities of 101.1 mg g-1 and 70.83 mg g-1, respectively-significantly higher than many reported values in the literature. The positive values of ΔH0 and ΔS0 indicate an endothermic process, with TC removal mechanisms influenced by physical interactions, such as hydrogen bonding, electrostatic interaction, and π-cation with the surface functional groups of the LDH adsorbents. These results suggest that LDH-MgAl and LDH-MgFe are promising adsorbents for the removal of TC from water.