摘要
运用1H→13CCP／MASNMR、29SiMASNMR、IR、XRD和元素分析等表征方法，研究了以四丙基溴化铵（TPABr）为模板剂的合成体系中，Ti酯和模板剂用量以及不同碱源对TS-1分子筛的影响，考察了不同Ti含量固体样品催化丙烯环氧化反应．实验结果表明：随着凝胶中Ti酯用量的增加，制得的分子筛结构对称性由单斜晶系逐渐向正交晶系转变，其丙烯环氧化活性也相应增加．尽管凝胶中所加减源只调变凝胶碱度而不起模板剂作用，然而凝胶的强碱环境对骨架钛原子引入有利．当凝胶中TPABr／SiO2摩尔比值在0．05－0.25之间时，TPABr加入量的变化不影响TS－1分子筛中骨架钛含量．
The influences of the content of titanium, the variety of the alkali and the amouuts of the templates in the gels on the syntllesis of the TS-1 zeolites prepared by means of tetrapropylammonium bromide (TPABr) as a template were investigated by 1H→13C CP/MAS NMR, 29SiMAS NMR, IR, XRD and element analysis techniques. The results showed that the structures of the resultant TS-1 zeolites were transterred from monoclinic symmetry to orthorhombic symnictry with the increase of the titanium content in the framework. The added alkali didn't act as a template in the synthesis of TS-1 zeolites, but the strong alkali conditions were of benefit to the incorporation of the titanium atoms into the lattices. When the molar ratios of TPABr/SiO2 in the gels varied from 0.05 to 0.25, the Ti conteut in the framework showed independence of the amounts of TPABr in gels.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
1998年第10期906-912,共7页
Acta Physico-Chimica Sinica
关键词
TPABr
模板剂
钛硅分子筛
催化剂
合成
TS-1
^(29)Si MAS NMR, ~1H→^(13)C CP/MAS NMR, IR, TS-1 zeolites, Tetrapropylammonium bromide
