Abstract: The oxidation reaction is the key process of titanium dioxide preparation by chlorination process,while scarring is a bottleneck restricting long-term operation of oxidation reactor.Therefore,grasping the crux of scar formation is the foundation and key to extend the operation period of oxidation reactor.Accordingly,on the basis of detection results of scarring materials of rutile TiO₂ prepared in oxidation reactor by gas phase oxidation method in the production site,this thesis analyzed the reasons for scarring in oxidation reactor through simulation calculations and scarring simulation tests.And this work also proposed the optimization measures for scarring prevention in oxidation reactor,combining with the design structure of existing large-scale oxidation reactor in China.