论文部分内容阅读
采用高温水热嫁接的方法,通过调节反应溶液的p H和水热处理温度,成功地将金属铬离子嫁接到SBA-15氧化硅骨架上,制备得到高度规整有序的介孔孔道结构的Cr/SBA-15催化剂,并研究了Cr/SBA-15在以乙腈为溶剂,H_2O_2为氧化剂的环己烷催化氧化反应中的性能。结果表明,当p H=3,Si/Cr摩尔比为15时,合成的Cr/SBA-15催化剂具有高度有序的二维六方介孔结构,同时表现出良好的催化活性和选择性。反应温度为80℃,反应时间为4 h条件下,环己烷催化氧化的转化率可达17%,环己酮和环己醇的选择性分别为65%、35%。Cr/SBA-15催化剂重复使用3次后活性基本不变,表明该催化剂具有良好的稳定性。
The high-temperature water-grafting method was adopted to successfully prepare the highly ordered and ordered mesoporous structure of Cr / Ti by the grafting of metal chromium ions onto the SBA-15 silica framework by adjusting the pH of the reaction solution and the hydrothermal treatment temperature. SBA-15 and the catalytic performance of Cr / SBA-15 in cyclohexane oxidation with acetonitrile as solvent and H 2 O 2 as oxidant. The results show that the synthesized Cr / SBA-15 catalyst has a highly ordered two-dimensional hexagonal mesoporous structure with p H = 3 and Si / Cr molar ratio of 15, and exhibits good catalytic activity and selectivity. Under the condition of reaction temperature 80 ℃ and reaction time 4 h, the conversion of cyclohexane to catalytic oxidation can reach 17%, and the selectivity to cyclohexanone and cyclohexanol is respectively 65% and 35%. The activity of Cr / SBA-15 catalyst remained unchanged after repeated use for 3 times, indicating that the catalyst has good stability.