Manufacturing method of sulfur by alkylation of waste sulfuric acid

The invention belongs to the field of chemical industry, and in particular relates to a manufacturing method of sulfur by alkylation of waste sulfuric acid. The method comprises the following steps: mixing waste sulfuric acid spray with compressed air, and then sending to an incinerator to be cracked at high temperature, and entering into a water scrubber to wash out impurities in a cracking furnace gas; dissolving calcium sulfide in an ethanol solvent, controlling the mass ratio of ethanol to calcium sulfide to be (3-10): 1, introducing the cracking furnace gas under stirring conditions, then carrying out filtering separation to obtain a filtrate and a solid reaction product containing sulfur, calcium sulfite and calcium sulfate, wherein the filtrate is taken as a reaction solvent to be recycled, and carrying out sulphur purification on the separated solid reaction product to obtain pure sulfur. The manufacturing method of sulfur by the alkylation of the waste sulfuric acid provided by the invention has the