A process for obtaining sulphur from hydrogen sulphide (from natural gas or crude oil). It involves two stages. First, part of the hydrogen sulphide is oxidized to sulphur dioxide:2H2S+3O2 → 2SO2+2H2O Subsequently, the sulphur dioxide reacts with hydrogen sulphide to produce sulphur:SO2+2H2S → 3S+2H2O The second stage occurs at 300°C and needs an iron or aluminium oxide catalyst.
2H2S+3O2 → 2SO2+2H2O
SO2+2H2S → 3S+2H2O