用盐酸改性处理NaZSM--5得到HZSM--5分子筛载体, 再用溶胶--凝胶法在NaZSM--5和HZSM--5表面合成TiO2前驱体, 将其煅烧制备出TiO2/ZSM--5负载型光催化剂。分别用扫描电镜、X射线衍射、傅里叶变换红外光谱和BET氮吸附对光催化剂的表面形貌、晶相结构和比表面积进行表征, 研究了NaZSM--5分子筛盐酸改性对TiO2/ZSM--5光催化剂的影响。结果表明, 盐酸改性对NaZSM--5分子筛骨架结构的影响不大, 但是使其结晶度有所降低。负载后TiO2的晶粒尺寸明显减小, TiO2/ZSM--5光催化剂的比表面积比纯TiO2有较大增长。对NaZSM--5分子筛盐酸改性提高了TiO2/ZSM--5对甲基橙的吸附和光催化降解能力。重复使用四次后, TiO2/ZSM--5光催化剂的光催化降解率下降为初次使用时的82.4%。
HZSM--5 zeolite was prepared by modification of NaZSM--5 zeolite with 0.3 mol/L hydrochloric acid. Photocatalysts of TiO2/NaZSM--5 and TiO2/HZSM--5 were prepared by dispersing TiO2 precursor onto the surface of NaZSM--5 and HZSM--5 zeolites using sol--gel method followed by calcination process, and the photocatalysts were characterized. The results show that the structure of the zeolite does not noticeably change after modification of NaZSM--5 by HCl, but its crystallinity reduces. Crystalline size of TiO2 decreases obviously after loading. The adsorption capacity of methyl orange and photocatalytic activity as well as surface area of the supported TiO2/ZSM--5 photocatalyst are significantly increased compared with that of bare TiO2. Further improvements of the properties were achieved after hydrochloric acid modification of the zeolite. Degradation rate of TiO2/HZSM--5 is 82.4% of the initial activity after the photocatalyst was reused for 4 times.
参考文献
| [1] | |
| [2] | |
| [3] | |
| [4] |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%