Oxidizing properties of sulfuric acid: can it oxidize hydrochloric acid to chlorine?
Concentrated sulfuric acid cannot oxidise chloride or fluoride, see here for a detailed explanation here

Concentrated sulfuric acid is not a strong enough oxidizing agent to oxidize fluoride or chloride. In those cases, only the steamy fumes of the hydrogen halide—hydrogen fluoride or hydrogen chloride—are produced. In terms of the halide ions, fluoride and chloride are not strong enough reducing agents to reduce the sulfuric acid. This is not the case for bromides and iodides.