Preparation of ruthenium-loaded CNT-TiO2 nanohybrids and their catalytic performance for the selective oxidation of benzyl alcohol
-
摘要: 以CNTs为基质，钛酸异丙酯为钛源，采用水热法制备CNT-TiO2复合物。采用扫描电子显微镜和X射线衍射等技术手段研究CNT-TiO2复合物的形貌和晶型结构特征，通过光学显微镜等技术手段研究TiO2、CNT-TiO2固体纳米颗粒形成的乳液体系的特征。以苯甲醇选择氧化制备苯甲醛为探针反应，研究浸渍法所制负载型钌基TiO2、CNT-TiO2乳液催化剂的催化反应性能，催化剂载体的乳化能力与其催化性能之间的规律性关系。结果发现：CNT-TiO2复合物的乳化能力强于TiO2颗粒，易形成乳液体积大及乳滴分布均匀的乳液体系；负载型Ru/CNT-TiO2催化剂的催化活性高于Ru/TiO2；催化剂载体的乳化能力与其催化活性密切相关，载体的乳化能力越强催化活性越高；CNT-TiO2复合物在苯甲醇选择氧化反应体系中起到了催化剂载体和固体乳化剂的双重作用。
-
关键词:
- CNT-TiO2复合物 /
- 苯甲醇氧化 /
- 乳液催化
Abstract: CNT-TiO2 nanohybrids were synthesized using CNTs as a substrate and isopropyl titanate as a titanium source by a hydrothermal method. The nanohybrids were characterized by SEM and XRD, and their dispersion ability as an emulsion was investigated by optical microscopy. Ruthenium was loaded onto TiO2 and the nanohybrids by an impregnation method, and their catalytic performance was evaluated by the selective oxidation of benzyl alcohol to benzylaldehyde. The mechanism involved in the reaction was proposed. Results show that the dispersion ability of the CNT-TiO2 nanohybrids, judged by the numbers of uniform oil droplets in water per unit liquid volume, is better than that of TiO2. The catalytic activity and selectivity of the Ru/CNT-TiO2 for the selective oxidation reactions are higher than for Ru/TiO2, indicating that they are closely related to the dispersion ability of the catalysts as emulsions. -
点击查看大图
计量
- 文章访问数: 1422
- HTML全文浏览量: 70
- PDF下载量: 1487
- 被引次数: 0
下载:
