The invention relates to an
alkylation method, which comprises the following steps: mixing
isobutane and C3-C5 olefin gas to form mixed
raw material gas, dispersing concentrated
sulfuric acid into liquid drops with the size of 0.001-500 [mu]m, mixing the mixed
raw material gas with the concentrated
sulfuric acid liquid drops, and then carrying out
quenching treatment under the conditions that the temperature is -20 to 20 DEG C and the pressure is 0.1-1 MPa, so that the mixed
raw material gas is subjected to
phase change condensation and is kept for 0.1-10 seconds; and the
reaction temperature is adjusted to -20 DEG C to 10 DEG C, the reaction pressure is kept to be 0.1-1 MPa, and the materials are subjected to an
alkylation reaction. The method comprises the following steps: mixing a mixed raw material gas with finely dispersed
sulfuric acid liquid drops, condensing the raw material gas on the surface of the sulfuric acid liquid drops under a
quenching condition to form reaction liquid drops, further controlling the
reaction conditions, taking sulfuric acid as a catalyst, enabling the condensed raw material gas to quickly generate
alkylation reaction, and enabling olefin and
alkane to react according to a molecular ratio close to 1:1, so that side reactions are reduced, and the alkylation reaction efficiency is improved.