The invention relates to a
sulfur tolerant catalyzing process for preparing low carbon
alcohol from synthesis gas and co-producing
natural gas, which comprises the following steps: performing a synthetic reaction by contacting the synthesis gas with a
sulfur tolerant low carbon
alcohol synthetic catalyst after the synthesis gas is subjected to coarse desulphurization; condensing the synthetic product to obtain a
liquid phase of
alcohol-water-oil and a
tail gas mixture consisting of CO, H2, CO2, C1-C5
hydrocarbon, performing a low carbon
alcohol synthesis reaction on a part of the
tail gas mixture for recycling, and performing
methanation on the other part of the
tail gas mixture; separating oil from water in the
liquid phase of the alcohol-water-oil to obtain an oil product and alcohol water, and separating alcohol from water in the alcohol-water mixture to obtain low carbon alcohol and water; performing
methanation on the tail gas in the presence of the
sulfur tolerant
methanation catalyst and under the condition of
methane conversion; condensing a methanation product to obtain a
liquid phase of oil and alcohol water and a gas containing CH2, CO2, CO, H2, C2-C5
hydrocarbon, and performing the methanation on a part of the gas mixture of CH4, CO2, CO, H2, C2-C5
hydrocarbon for recycling; and sending the other part of the gas mixture to a CO2 separation device, and separating CO2 to obtain an SNG. The process has the advantages of having simple steps and low cost, organically
coupling the low carbon
alcohol synthesis process with the methanation process, improving the carbonutilization rate and realizing co-production and
complementation of the low carbon alcohol and the
natural gas.