Improvement of methyl mercaptan removal by ZnO-coated TiO2

CH3SH is listed as one of the causes of a stink and indoor air-pollution. As a method for the removal of CH3SH, we paid attention to TiO2 photocatalyst that is harmless and has especially strong oxidation power. The oxidation decomposition of photocatalyst occurs when adsorption occurs, but TiO2 with the character of acid solid is not necessarily suitable for the adsorption of CH3SH that is an acid gas. Then, we tried to cover the surface of TiO2 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 of TiO2 was partially covered with ZnO. It was thought that efficient adsorption occurred due to the surface coating, and afterwards photolisis was generated by part of TiO2 not covered. Therefore, we think that the removal performance is improved by covering TiO2 with ZnO suitable for the adsorption of CH3SH that is an acid gas and the rate of the coating is important.