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[Display omitted] • Performances of H 2 S conversion technologies are critically reviewed. • Except for Claus process, other H 2 S conversion technologies are still in R&D phase. • Plasma, electrochemical/photocatalytic conversion could be powered by renewables. • Pros and cons, as well as the TRL of each technology are compared and discussed. • H 2 is the main product of interest derived from H 2 S. Hydrogen sulfide (H 2 S) is a toxic gas released from natural occurrences (such as volcanoes, hot springs, municipal waste decomposition) and human economic activities (such as natural gas treatment and biogas production). Even at very low concentrations, H 2 S can cause adverse health impacts and fatality. As such, the containment and proper management of H 2 S is of paramount importance. The recovered H 2 S can then be transformed into hydrogen (H 2) and various value-added products as a major step towards sustainability and circular economy. In this review, the state-of-the-art technologies for H 2 S conversion and utilization are reviewed and discussed. Claus process is an industrially established and matured technology used in converting H 2 S to sulfur and sulfuric acid. However, the process is energy intensive and emits CO 2 and SO 2. This calls for more sustainable and energy-efficient H 2 S conversion technologies. In particular, recent technologies for H 2 S conversion via thermal, biological, plasma (thermal and non-thermal), electrochemical and photocatalytic routes, are critically reviewed with respect to their strengths and limitations. Besides, the potential of diversified value-added products derived from H 2 S, such as H 2 , syngas, carbon disulfide (CS 2), ammonium sulphate ((NH 4) 2 SO 4), ammonium thiosulfate ((NH 4) 2 S 2 O 3), methyl mercaptan (CH 3 SH) and ethylene (C 2 H 4) are elucidated in detail with respect to the technology readiness level, market demand of products, technical requirements and environmental impacts. Lastly, the technological gaps and way forward for each technology are also outlined. [ABSTRACT FROM AUTHOR]