羟基改性Ag/MCM-41催化剂上甲醛的催化氧化性能

FORMALDEHYDE CATALYTIC OXIDATION OVER Ag/MCM-41 CATALYSTS MODIFIED WITH HYDROXYL GROUP

采用等体积浸渍法制备Ag/MCM-41催化剂,通过添加NaOH溶液对催化剂进行羟基改性,考察了不同羟基浓度改性后的催化剂上甲醛催化氧化反应性能。甲醛固定床催化反应评价实验结果表明:经0. 1 mol/L NaOH改性后的催化剂表现出较好的甲醛低温催化活性。氮气物理吸附、X射线衍射(XRD)、透射电镜(TEM)、红外光谱分析(IR)的表征结果表明:当NaOH添加量为0. 1mol/L时,催化剂表面形成了更多的活性羟基基团,从而促进了活性金属银粒子的分散,提高了甲醛催化反应活性。

Ag/MCM-41 catalysts were prepared by incipient-wetness impregnation method in this paper, and through adding NaOH solution to modify the catalysts with hydroxyl group, the catalytic oxidation performance of formaldehyde over the Ag/MCM-41 catalyst modified with different concentrations of hydroxyl group was investigated.The results of formaldehyde fixed bed catalytic oxidation reaction activity showed that, a good low-temperature catalytic activity of formaldehyde was found in the catalyst modified with 0.1 mol/L NaOH.The results of the characterizations such as N 2 physical adsorption, X-ray diffraction (XRD), transmission electron microscopy (TEM), and infrared spectroscopy (IR) showed that: more active hydroxyl groups were formed on the surface of the catalyst when 0.1mol/L NaOH was added, thus having facilitated dispersion of active metallic silver particles, and improved catalytic activity of formaldehyde.