2025, Vol. 6, Issue 2, Part B

Sulphur chemistry is one of the core of sustainable organic synthesis where molecular innovation and environmental responsibility is linked. In the past sulphur based transformations involved the reliance on toxic reagents, dangerous waste streams and energy-demanding processes. Nevertheless, the alternative developments put in existence as of late owing to the guidelines of green chemistry have changed these operations giving selective, efficient as well as environmentally aware pathways. The combination of renewable energy systems, recyclable catalysts and benign solvents has reversed classical reactions to the following, sulfonation, thiolation and oxidation. New approaches, including photocatalytic activation and electrochemical activation, allow using high-yield sulphur conversions at ambient conditions, and bio-based alternatives can be developed, namely the thiolation via biocatalytic means in aqueous solutions. The paper will explore the history of green sulphur chemistry by the innovative catalyst, intensifying the process, and its integration in the circular economy. It has quantitative measures such as E-factor, atom economy, and life-cycle assessment (LCA), which compare the conventional and sustainable methods. Implementation of artificial intelligence (AI), digital twins, and renewable sources are a step to a system of autonomous and zero-waste production of sulphur. Given the convergence of catalysis, biotechnology and data science, green sulphur chemistry is a redefining approach that has the potential of attaining environmental sustainability in the worldwide chemical sector.