Improvement of methyl mercaptan removal by ZnO-coated TiO2

Abstract

CH3SH is listed as one of the causes of a stink and indoor air-pollution. As a method for the removal of CH 3 SH, we paid attention to Ti0 2 photocatalyst that is harmless and has especially strong oxidation power. The oxidation decomposition of photocatalyst occurs when adsorption occurs, but Ti0 2 with the character of acid solid is not necessarily suitable for the adsorption ofCH 3 SH that is an acid gas. Then, we tried to cover the surface ofTi0 2 with ZnO that is a harmless photocatalyst and base solid. We succeeded in coating it by the simple method. As a result, it was confirmed that adsorption ability in the shade place was improved by coating it and the removal performance under the irradiation of 254nm UV lamp was improved, too. When the shape of the surface was observed by using SEM-EDAX, it was confirmed that the surface ofTi0 2 was partially covered with ZnO. It was thought that efficient adsorption occurred due to the surface coating, and afterwards photolisis was generated by part ofTi0 2 not covered. Therefore, we think that the removal performance is improved by covering Ti0 2 with ZnO suitable for the adsorption ofCH 3 SH that is an acid gas and the rate of the coating is important.