热处理条件对介孔Al_2O_3结构性质的影响  

Influence of heat treatment on structure-property of mesoporous alumina

作　　者：许争[1,2,3] 常弈[1,2,3] 林倩[1,2,3] 潘红艳[1,2,3] 曹建新[1,2,3] 刘飞[1,2,3] 

机构地区：[1]贵州大学化学与化工学院,贵州贵阳550025 [2]贵州省绿色化工与清洁能源技术重点实验室,贵州贵阳550025 [3]贵州省矿产资源高效利用与绿色化工技术特色重点实验室,贵州贵阳550025

出　　处：《材料热处理学报》2017年第8期1-6,共6页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(21666007);贵州省百层次创新型人才专项(黔科合平台人才2016-5655);贵州省重点科学技术基金(黔科合JZ字2014-2007)

摘　　要：以氯化铝和氨水反应制得拟薄姆石为前驱体,研究了拟薄姆石前驱体热处理性质,考察了焙烧温度对介孔Al_2O_3微观结构的影响,通过焙烧升温速率调控了γ-Al_2O_3表面酸碱性,借助XRD、SEM、BET及NH3/CO2-TPD等手段对焙烧产物晶相组成、微观形貌、孔结构及表面酸碱性进行分析表征。结果表明,焙烧温度对介孔Al_2O_3晶相组成、微观形貌、孔结构影响较大。随焙烧温度升高,Al_2O_3结晶度逐渐增大,且焙烧温度不同,Al_2O_3晶型不同,焙烧温度为600℃时制得了比表面积240.23 m^2·g^(-1),介孔孔容0.602 cm3·g^(-1),平均孔径10.71 nm的纳米球形介孔γ-Al_2O_3。升温速率对600℃焙烧制得γ-Al_2O_3表面酸碱性质具有较大影响,焙烧升温速率越快,表面酸碱强度越强。升温速率为5℃·min^(-1)时,表面具有最大弱酸(0.342 mmol·g^(-1))和弱碱量(0.322 mmol·g^(-1))。The heat treatment properties of boehmite precursors fabricated by reaction of aluminum chloride and ammonia were studied.The effect of calcination temperature on microstructure of mesoporous Al2O3 was investigated.The surface acid-alkali of γ-Al2O3 was controlled by changing the heating rate.The crystalline phase,morphology,pore structure and surface acid-alkali of alcined products were characterized by means of XRD,SEM,BET and NH3/CO2-TPD techniques.The results show that the calcination temperature has a great influence on the crystalline phase composition,morphology and pore structure of the mesoporous Al2O3.With the increasing of calcination temperature,the crystallinity of the Al2O3 increases gradually,and the Al2O3 crystal is different at different calcination temperatures.The nanoscale spherical γ-Al2O3 with the specific surface area of 240.23 m2·g（-1）,mesopore pore volume of 0.602 cm3·g（-1）and average pore diameter of 10.71 nm is successfully fabricated at 600 ℃.The heating rate also has a significant influence on the acid-alkali properties of the γ-Al2O3.The higher the heating rate is,the stronger the acid-alkali strength is.When the heating rate is 5 ℃·min（-1）,the surface of the γ-Al2O3 fabricated at 600 ℃ has the maximum amount of weak acid（0.342 mmol·g（-1）） and weak base（0.322 mmol·g（-1））.

关 键 词：介孔Al2O3 焙烧温度 升温速率 结构性质 表面酸碱性 

分 类 号：TB321[一般工业技术—材料科学与工程]