镁铝尖晶石催化剂载体的制备及表征  

Preparation and characterization of MgAl_2O_4 spinel as catalyst support

作　　者：张超武[1] 张利娜[1] 张楠[1] 王夏云[1] 王芬[1] 

机构地区：[1]陕西科技大学材料科学与工程学院,陕西西安710021

出　　处：《陕西科技大学学报（自然科学版）》2016年第6期42-46,58,共6页Journal of Shaanxi University of Science & Technology

基　　金：国家自然科学基金项目(51171096);陕西省科技厅自然科学基金项目(2014JM6233)

摘　　要：以偏铝酸钠和氢氧化镁为原料,采用共沉淀-水热法合成镁铝尖晶石载体.利用XRD、SEM、TG-DSC和N2吸附-脱附等测试手段对样品的结构和性能进行了表征,并研究了水热时间、烧结温度等条件对镁铝尖晶石载体的结构和性能影响.所得结果表明,水热反应后得到的前驱物主要是镁铝羟基化合物,水热时间24h能够形成镁铝尖晶石良好的片状骨架结构.在实验范围内镁铝尖晶石有良好的介孔结构,600℃烧结就得到了完整晶态骨架结构,随着温度的提高,样品的XRD衍射峰强度不断增加,骨架结构更完整,温度高于900℃,镁铝尖晶石骨架结构塌陷,因此镁铝尖晶石催化剂载体的最佳烧结温度为800℃.The magnesium aluminate spinel catalyst carriar were synthesized by a coprecipitation and hydrothermal method,using sodium aluminate and magnesium hydroxide as the raw materials.The samples were characterized by XRD,SEM,TG-DSC,and N2 adsorption-desorption isotherms to study the effect of hydrothermal and sintering temperatures on the structures and properties of magnesium aluminate spinel.The results showed that the precursor is mainly magnesium aluminum hydroxyl compounds after coprecipitation and hydrothermal procedures.The good flake skeletal structure is formed by hydrothermal time of 24 h.The final magnesium aluminate spinel has well-crystalline mesoporous structure.Witnin experimental range,the promoted crystalline skeleton structure was formed at 600 ℃.And with the increment of calcination temperature,the XRD diffraction peak intensity of samples increased gradually and the flake skeletal structure was improved.When the sintering temperature was above 900 ℃,the skeleton structure of magnesium aluminate spinel collapses.So the best sintering temperature is 800 ℃for magnesium aluminate spinel catalyst carriar.

关 键 词：镁铝尖晶石 催化剂载体 水热法 

分 类 号：O64[理学—物理化学]