SO_4^(2-)/ZrO_2-SiO_2 超强酸催化剂研究 (Ⅱ )——结构表征(英文)  

Study on the Superacid Catalyst SO_4^(2-)/ZrO_2-SiO_2 (Ⅱ): Characterization of Structure

作　　者：廖世军[1] 王乐夫[1] 杨兆禧[1] 梁路一 黄新辉 黄仲涛[1] 

机构地区：[1]华南理工大学化工学院,广东广州510640

出　　处：《华南理工大学学报（自然科学版）》2001年第12期38-41,共4页Journal of South China University of Technology(Natural Science Edition)

基　　金：广东省自然科学基金资助项目 (990 6 46 )~~

摘　　要：采用FTIR ,XRD ,XPS和TG_DTA等表征了一组具有不同组成的由沉淀 -混合沉淀法制得的SO2 - 4/ZrO2 _SiO2 超强酸催化剂 .由实验结果可知 ,催化剂的超强酸点可能是由于SO2 - 4基团与二元氧化物中的锆相互作用而产生的 .与SO2 - 4/ZrO2 催化剂不同的是 ,即使在 6 5 0℃以上温度下焙烧的SO2 - 4/ZrO2 _SiO2 催化剂也是无定型的 .80 0℃以上焙烧前体二元氧化物时 ,按照锆硅比的不同将出现两种不同的情况 ,硅锆比小于 8时 ,其XRD谱图上出现属于四方晶型的二氧化锆的衍射峰 ;而当硅锆比大于 8时 ,XRD谱图显示产生了一种新型的结晶体 .研究结果表明 ,SO2 - 4基团与二元氧化物中Zr原子作用形成了酸性中心 .A series of SO 2- 4/ZrO 2_SiO 2 catalysts with different composition, which were prepared by a precipitating/mixing precipitate method, were characterized by FTIR, XRD, XPS and TG_DTA. Unlike SO 2- 4/ZrO 2 catalyst, the SO 2- 4/ZrO 2_SiO 2 catalysts are usually amorphous even calcined at 650 ℃. When the precursor binary oxides were calcined above 800 ℃, two different types of XRD pattern appeared according to the ratio of SiO 2 to ZrO 2. As the ratio is below 8, the XRD patterns can be attributed to the tetragonal zirconia existed in catalysts as micro particles. Whereas, as the ratio is above 8, the XRD patterns show that a new type of crystal was formed. It is suggested that the interaction of SO 2- 4 group with Zr in binary oxide result in the forming of acid sites.

关 键 词：硫酸化处理 二化氧化物 结构表征 超强酸催化剂 二氧化硅 二氧化锆 硅锆比 

分 类 号：O643.36[理学—物理化学]