Preparation method of triphenyl sulfonium salt

The invention discloses a preparation method of triphenyl sulfonium salt. Triphenyl sulfonium is prepared from benzene, thionyl chloride and alchlor, and the reaction formula is described in the specification, wherein M is alkali metal or hydrogen, alkali metal can be K or Na, and X is halogen anion or composite anion. According to the method, the used raw materials are chip and easily-obtained basic chemical raw materials, the cost of the raw materials is low, the production cost can be reduced greatly, the reaction conditions are moderate, and the method is easy to operate and realize industrialization.