Process for the desulfurization of gas containing hydrogen sulfide

Abstract From the Canadian patent

It was previously thought that the Claus reaction of sulfur dioxide and hydrogen sulfide in water to give elemental sulfur, without additives, gives very low conversion and that, some additives such as a buffer or a catalyst must be used to attain satisfactory hydrogen sulfide conversion. However it has, now been discovered that when hydrogen sulfide and sulfur dioxide are introduced in water simultaneously and continuously for a considerable period of time, at least until the water attains pH 2 or less, the conversion increases gradually and becomes steady at high levels. The present invention thus provides a process based on this factor, namely a liquid phase Claus reaction to form …