Display omitted •Desulfurization by ionic liquid has been carried out in a RPB.•CPLTBABIL/PEG-400 as absorbent has the best performance.•No obvious loss of desulfurization efficiency was observed during reutilization.•Desulfurization with IL in a continuous process was feasible with RPB. Desulfurization by ionic liquids (ILs) has attracted wide attention since ILs as green solvents can be recycled after desorption. However, the high viscosities of ILs limit the sulfur dioxide (SO2) absorption in gas-liquid contactors. In this work, a rotating packed bed (RPB) with excellent mass transfer performance was employed for SO2 removal with caprolactam tetrabutyl ammonium bromide (CPLTBAB) IL. Effects of rotational speed, temperature, liquid flow rate, and gas flow rate on the desulfurization efficiency were systematically studied. By optimization of the solvents, the desulfurization efficiency remains almost unchanged after multiple absorption and regeneration cycles, and the energy consumption during desorption process can also be reduced. These results indicated that the RPB combined with ILs has promising prospects for SO2 absorption and desorption in sulfuric acid plants.