Control method for optimizing reaction of mercury-free catalytic synthesis of vinyl chloride by using gas-permeable member

The invention provides a control method for optimizing a reaction of mercury-free catalytic synthesis of vinyl chloride by using a gas-permeable member. According to the method, a long rod-shaped gas-permeable member is arranged at the center of a converter row tube, a raw material gas enters a tubular converter from the upper portion, then according to a certain proportion, partially enters an annular gap catalyst bed layer, and partially enters the gas-permeable member, and the raw material gas entering the gas-permeable member flows from top to bottom along the axial direction of the gas-permeable member, and simultaneously diffuses outward by penetrating through gas-permeable pores of the gas-permeable member in the radial direction to enter the annular gap catalyst bed layer, so thata contact path between the raw material gas and a catalyst is improved, a reaction of the catalyst bed layer is uniform, and temperature distribution of the converter from top to bottom and the radialdirection from inside to