摘要
采用沉淀法制备了AlPxO(x=0,0.33,0.5,1.0,1.5,2.0)催化剂,通过XRD,FTIR,固体核磁共振,BET,NH3-TPD和CO2-TPD等手段对催化剂进行了表征,发现n(P)/n(Al)对催化剂结构及表面酸碱性质有很大影响.考察了AlPxO催化剂上以邻苯二酚和甲醇为原料,采用气相法一步合成愈创木酚的反应性能,并研究了催化剂表面酸碱性质对反应活性和选择性的影响.结果表明,催化剂表面同时存在一定量的弱酸和弱碱中心有利于提高愈创木酚的收率.
AlPxO(x=0, 0.33, 0. 5, 1.0, 1.5, 2.0) catalysts were prepared via precipitation method and characterized by means of XRD, FTIR, solid-state MAS NMR, N2 adsorption, NH3-TPD and CO2-TPD techniques. The morphology of the catalysts changes from amorphism to crystalline with the increase of n(P)/n(Al). Both the acidic and basic amouhts on the catalysts surface increase first with the increase of P contents [n(P)/n(Al)≤0. 5], and then decrease dramatically with further increasing P contents. Meanwhile, vapor-phase O-methylation of catechol with methanol was investigated over various AlPxO catalysts. Among them, AlP1.0O sample exhibits a good catalytic activity and selectivity to guaiacol, which resulted in the highest yield of guaiacol. This may mainly be attributed to the presence of suitable amounts of weak acid and base sites on the surface of the catalyst.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2005年第8期1492-1496,共5页
Chemical Journal of Chinese Universities
基金
吉林省科技发展计划项目(批准号:990546)
吉林大学创新基金(批准号:2002CX092)
教育部博士学科点基金(批准号:20040183003)
中国石油天然气集团公司(合同号:JTGS20040010)资助.
关键词
磷酸铝
邻苯二酚
愈创木酚
弱酸弱碱
Aiuminophosphates
Catechol
Guaiacol
Weak acid and base sites