Abstract: To solve the problem of the exceeding S content in tail gas from a titanium dioxide plant,the S content of titanium ore and titanium slag raw materials was compared and analyzed.The S content of the tail gas under different acid hydrolysis conditions was simulated using sulfuric acid.Verification test of the effect of hydrolysis process on the S content of acid hydrolysis tail gas was carried out.The results showed that the S content of titanium slag was 0.10%,lower than the 0.15% S content in titanium ore.The S in titanium slag acid hydrolysis tail gas mainly came from sulfuric acid.During the simulation test,with the increase of sulfuric acid concentration,the content of S in the exhaust gas gradually decreased and the extent of decrease gradually decreased.As the temperature increased,the S content of the exhaust gas gradually increased and the extent of increase decreased.During the titanium slag acid hydrolysis process verification test,as the reaction acid concentration decreased from 92% to 84%,the maximum reaction temperature decreased from 226 ℃ to 186 ℃,the acid hydrolysis rate decreased from 93.19% to 90.78%,and the S content in the tail gas decreased from 0.55 g to 0.09 g.S originated from sulfuric acid decreased from 91.1% to 44.4%.The acid-slag ratio showed almost no visible effect on the S content in the tail gas.