Metal Chloride-Functionalized Ionic Liquids for Highly Efficient H2S Conversion into Value-Added Elemental Sulfur: A Comprehensive Optimization Study and Techno-Economic Analysis

The efficient transformation of hydrogen sulfide (H2S) into valuable elemental sulfur is essential for addressing economic and environmental challenges. This study introduces metal chloride-functionalized ionic liquids (ILs) as high-performance catalysts for H2S capture and conversion under mild conditions. The most effective ILs, P666142CuCl4, achieved a remarkable conversion efficiency of 97.25% at ambient conditions (25 °C, 1 bar) with the addition of N,N-dimethylformamide (DMF) as a cosolvent. The catalyst demonstrated excellent recyclability over five cycles without significant degradation. Additionally, a comprehensive techno-economic analysis (TEA) confirmed the economic feasibility (in terms of capital and operating costs) of IL-based technology featuring P666142CuCl4, as compared to conventional methods such as the Claus and LO-CAT processes, highlighting its potential for industrial applications. © 2025 American Chemical Society.