GB471668A - Improvements in and relating to the manufacture of sulphur - Google Patents

Abstract

Sulphur is obtained in maximum yield from gases containing sulphur dioxide and/or sulphur trioxide by reaction with such an amount of substances containing hydrogen and/or carbon in free or combined form that in the resulting gaseous mixture, after removal of free sulphur, the concentrations (in volume percentage) of carbon oxysulphide, hydrogen sulphide and carbon disulphide, if present, satisfy the relation SO2/(COS+H2S+CS2)=1 or substantially 1. The gases may be treated with carbonaceous substances, or bodies containing carbon combined with oxygen and/or sulphur, e.g. carbon monoxide, carbon dioxide, carbon disulphide or carbon oxysulphide, or with hydrocarbons or mixtures containing both carbon and hydrogen, or bodies containing carbon and hydrogen combined with oxygen or sulphur, e.g. phenolic oils, hydrogen sulphide or water. According to an example, the gas to be treated contains 7 per cent sulphur dioxide, 10 per cent oxygen and 83 per cent nitrogen. This is reacted at 800 DEG C. with carbon so that the C/S ratio is 2,425, i.e. so that 29,1 gms. of carbon are gasefied for every 32 gm. of sulphur. The residual gases contain 0,3 per cent sulphur dioxide, 0,3 per cent carbon oxysulphide and 0,001 per cent of carbon disulphide and the sulphur yield is 92 per cent. The carbon may be injected in pulverized form into the gases, or the gases may be passed at temperatures of 800--1400 DEG C., over an excess of carbon, the speed being adjusted in accordance with the amount of gasefied carbon required, or a portion of the gases may be passed over carbon to give an excess of gasefied carbon, the remainder of the gases then being added in the required amount. A catalyst may be used if desired.