The aim of this work is to increase the yield of isoalkanes and improve the quality of the alkylate produced by optimizing the operating conditions of the reactor using the unsteady mathematical model. The theoretical significance of this work consists in obtaining new data on thermodynamic and kinetic regularities of the process of H2SO4-catalyzed isobutane alkylation with alkenes in an industrial reactor, substantiating the level of the reaction network detalization. It was also found that the alkylate yield increases by 400 tones/h with increasing the concentration of isobutane in the feedstock by1%, and the octane number of the produced alkylate increases by 0.8-1.0 ppm with increasing the concentration of isobutane in 1.3 times. It was shown that is necessary to maintain the acid at optimum level by controlling the fresh catalyst supply and withdrawing the deactivated acid, and the fresh catalyst flow rate can be calculated using the unsteady reactor model.