钛负载Mo7O_24^(6-)插层Si-Mg/Al-LDHs的制备及催化性能研究
Preparation and catalytic properties of supported titanium Mo7O_24^(6-)-Si-Mg/Al-LDHs
采用共沉淀和离子交换法制备含硅Mo7O_24^(6-)-Mg/Al型层状双金属氢氧化物，550℃焙烧4h，然后以甲苯为溶剂，钛酸四丁酯与焙烧产物表面羟基进行反应，将钛负载在焙烧产物中。通过X射线衍射（XRD）和红外光谱（FT-IR）对水滑石焙烧前后结构进行分析，结果表明，通过共沉淀和离子交换法得到结晶结构较为理想的插层水滑石前体，硅溶胶负载对水滑石晶体结构没有破坏，由于硅，钛原子合理匹配，钛以四配位形式分散在催化剂中，得到良好的催化效果。研究发现，催化剂（3）Ti-Mo7O_24^(6-)-（2.68）Si-Mg/Al-LDO在丙烯环氧化反应中具有较好的活性，双氧水的转化率达到85.16%，环氧丙烷的选择性达到78.39%。
Mo7O_24^(6-)-Si-Mg/Al layered double hydroxides was synthysized by the coprecipitation and ion-exchange methods.The sample was calcined at787K for 4 h, using toluene as solvent, tetrabutyl titanate reacted with surface hydroxyl (OH) groups of roasted product to produce Ti-Mo7O_24^(6-)-Si-Mg/Al-LDO. The LDH and LDO′s configuration are analized and characterized by IR, and XRD.Studies show that, the intercalated hydrotalcite precursors prepared by the coprecipitation and ion-exchange showed better crystal structure, Mo7O_24^(6-)-Mg/Al-LDO-supported silica gel was synthesized without disrupting the crystal structure. High dispersion of tetra-coordinated titanium is achieved by means of adjusting optimal combination of titanium and silicon atoms, hence the activity of the materials can be improved. The study found that （3）Ti-Mo7O_24^(6-)-（2.68）Si-Mg/Al-LDO was used as catalyst for epoxidation of propylene with the conversion rate 85.16% and selectivity of propylene oxide 78.39%.
李乃旭、张传明、张照明、宋建超、周建成
金属元素无机化合物化学工业无机化学工业精细化学工业
层状双金属氢氧化物插层水滑石负载钛环氧丙烷
layered double hydroxideIntercalated hydrotalciteSupported titaniumPropylene oxide
李乃旭,张传明,张照明,宋建超,周建成.钛负载Mo7O_24^(6-)插层Si-Mg/Al-LDHs的制备及催化性能研究[EB/OL].(2009-06-08)[2025-08-21].http://www.paper.edu.cn/releasepaper/content/200906-218.点此复制
评论