- 作者: 鄭淑芬 ; 李俊徹
- 作者服務機構: 台灣大學化學系
- 中文摘要: By refluxing the anatase form of TiO/sub 2/ powder in phosphoric acid, the surface acidity was observed to increase. The amount of acid was determined by n-butylamine titration in n-heptane media, and was found to be proportional to the reflux period in phosphoric acid. XRD patterns and IR spectra revealed that the products contained a mixture of the anatase form of TiO/sub 2/ and titanium phosphate phases. Based on the calculated acid density on the surface, part of the titrant, n- butylamine penetrated into the titanium phosphate layers. Further investigations using TGA, FT-IR and TEM techniques along with surface area measurements indicated that the titanium phosphate phase was coated over the TiO/sub 2/ phase. The surface acidity of the phosphoric acid treated anatase increased due to the substitution of Ti-OH groups by phosphate groups. Nevertheless, the chemical properties of the resultant surfaces were found to be influenced by the internal anatase phase. The kinetic data on the 2-propanol dehydration reaction, where the activation energies were found to decrease gradually with an increase in phosphate content, also support these conclusion.
- 英文摘要: --
- 中文關鍵字: Titanium Oxide; Surface Acidity; 2-Propanol; Dehydration; Catalytic Activity; Phosphoric Acid
- 英文關鍵字: 表面酸度;2-異丙醇;脫水反應;催化活性;磷酸;氧化鈦