Photocatalytic and biological degradation processes to mineralize pharmaceutically active compounds and catalyst recovery: A review

Over the past few decades, the escalating issue of water pollution has primarily originated from the direct discharge of industrial and municipal waste. The perilous ramifications of waste laden with pharmaceutically active compounds (PhACs) are particularly concerning, largely due to the rise of antibiotic-resistant microbes. This makes the implementation of effective treatment processes for mitigating PhAC pollution increasingly difficult. This review highlights the proliferation of PhACs, their risk to aquatic life, and the subsequent development of antimicrobial-resistant microbes. Photocatalysis has emerged as a promising, environmentally friendly approach for pollutant degradation, but its practical application remains limited due to challenges such as poor photocatalytic efficiency, incomplete mineralization, generation of intermediate products, and inefficient catalyst recovery. This review explores bio-based modifications of photocatalytic materials to enhance catalytic performance by lowering the bandgap, delaying electron-hole pairs recombination, and improving hydrophilicity. This review also introduces a novel integrated mechanism combining photocatalytic degradation, membrane-assisted photocatalyst recovery, and biological degradation of PhACs and their intermediates, offering valuable insights for researchers and industrialists.