摘要
本文用XRD、TG-DTG-DTA、SEM和化学分析等多种实验手段研究了浸渍H_2SO_4的无定形ZrO_2在不同焙烧温度下的晶化和相变,失水和失硫等过程.实验结果表明,这些过程与超强酸的形成密切相关,在ZrO_2/SO_4^(2-)超强酸体系中不存在水和游离H_(2)SO_(4),体系超强酸强度最高时ZrO_2呈四方晶相,晶体表面约有略少于1/3的Zr原子与SO_4^(2-)根相结合.
The crystallization,phase transition,dehydration and desulfuration of amorphous ZrO2 impregnated by H2SO4 under various calcination temperatures were studied with XRD,TG-DTG-DTA,SEM and chemical analysis methods.It was found that all these processes are evidently related with the formation of superacid.There are no water and free H2SO4 present in the ZrO2/SO42-superacid system,and the acid strength of the superacid system reaches the maximum as the amorphous ZrO2 transforms into a tetragonal crystal phase and slightly less than 1/3 of the surface Zr atoms are bonded with SO42-radicals.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
1992年第12期1498-1502,共5页
Chemical Journal of Chinese Universities
关键词
超强酸
二氧化锆
硫酸根
ZrO_2/SO_4^(2-)system,Superacid,Synthesis
