摘要
在热压反应釜中利用蔗糖将重铬酸钾直接还原成水合氧化铬,利用TG-DTA,XRD,FT—IR,BET比表面积测定等表征技术对得到的水合氧化铬在空气气氛中的热分解过程进行了研究。结果表明,水合氧化铬热分解过程中存在Cr3+→Cr6+→Cr3+氧化还原过程;O2分子的存在加速了晶型α—Cr2O3的形成;同时发现在“发热或发光现象”发生之前,部分α—Cr2O3微晶已经形成。对热分解过程的机理做了简单的讨论。
Hydrated chromic oxide was directly synthesized by the reduction of potassium dichromate with sucrose in an autoclave. The course of its thermal decomposition was investigated by using the TG, DTA, XRD, FT - IR and BET specific surface area analysis. The results show that there is an oxidation - reduction process of Cr3 + -Cr6 + -Cr3+ during the thermal decomposition of hy-drated chromic oxide. The presence of O2 accelerates the transformation , which leads to formation of micro crystalline a - Cr2O3. It is also found that some of a - Cr2O3 micro crystallites have been formed before the glow phenomenon occurs at 390 C . The mechanism for this thermal decomposition is discussed.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2002年第z1期116-119,123,共5页
Journal of The Chinese Ceramic Society
基金
国家863计划资助项目(2001AA647010)。
关键词
热分解
水合氧化铬
结晶
重铬酸钾
蔗糖
微晶
thermal decomposition
hydrated chromic oxide
crystallization
potassium dichromate
sucrose
micro crystallite
