摘要
以正硅酸乙酯（TEOS）、钛酸丁酯（TBOT）、四丙基氢氧化铵（TPAOH）分别作硅源、钛源及模板剂水热合成了TS-1分子筛.考察了TEOS水解时的水硅比、TEOS水解温度、TPAOH用量及添加三乙醇胺（TEA）对TS-1分子筛合成及其性能的影响.采用XRD、SEM、N2吸附等手段对试样进行表征,同时以环己酮氨肟化反应考察试样的催化活性.结果表明,TEOS水解过程中,n（H2O）/n（S iO2）在20-40的范围内对TS-1的合成及性能影响不大.水解温度较高（60℃）时,加入少量TPAOH（n（TPAOH）/n（S iO2）=0.125）即可得到性能较好的TS-1,而在水解过程中添加适量TEA则能进一步改善TS-1分子筛的性能.在水解温度为60℃、n（S iO2）∶n（TPAOH）∶n（TEA）∶n（H2O）为1∶0.125∶0.065∶20时合成出的TS-1用于环己酮氨肟化反应,环己酮转化率达到90.7%,环己酮肟选择性达到92.4%,催化活性与高TPAOH用量合成的TS-1接近,而TPAOH的用量大大降低.
TS-1 was synthesized via hydrothermal method with tetraethyl orthosilicate （TEOS）, tetraethyl orthotitanate （TBOT） and tetrapropylammonium hydroxide （TPAOH） as silica source, titanium source and template, respectively. Besides, triethanolamine （TEA） was added during the synthesis to improve the properties of TS-1 while lowing the TPAOH concentration. The influence of the TEOS hydrolysis conditions, such as H2O/SiO2 molar ratio, the hydrolysis temperature, TPAOH/SiO2 molar ratio and the addition of TEA were studied. The products were characterized by XRD, SEM, N2 adsorption and the ammoximation of cyclohexanone reaction. The results indicated that H2O/SiO2 molar ratio ranging from 20 -40 had little effect on the synthesis of TS-1. Higher hydrolysis temperature could lead to the formation of TS-1 exhibiting better properties at low TPAOH/SiO2 molar ratio of 0. 125. The addition of TEA in the TS-1 synthesis solution could improve the catalytic properties of the resulting TS-1 when lower TPAOH concentration was applied. When TEOS was hydrolyzed at 60℃ and the molar ratio of n （ SiO2 ） ： n（H2O）： n（TPAOH） ： n（TEA） was 1：20： 0. 125： 0. 065, the conversion of cyclohexanone and selectivity of cycloexanone oxime could reach 90. 7% and 92.4% , respectively.
出处
《南京工业大学学报（自然科学版）》
CAS
2007年第3期7-12,共6页
Journal of Nanjing Tech University(Natural Science Edition)
基金
国家自然科学基金资助项目(20201007)
