Process to prepare a coke oven gas LNG

Preparing one kind of coke oven gas is LNG process degreasing coke oven gas, after removal from benzene and naphthalene and other impurities, a three-stage sulfur-tolerant methanation reaction is directly supported on the sulfur-tolerant methanation catalyst is a molybdenum substrate, and Rectisol by a sulfur removal, CO2 C2-4 hydrocarbons and other impurities, and finally through a cryogenic liquefied liquefied natural gas after separating N2 and H2, etc. have a methane content of 97% or more. The invention has simple process, less investment in equipment, low overall energy consumption and excellent natural product advantages.