盐卤硼酸盐化学 ⅩⅫ.天然钠硼解石矿物的热行为研究

Chemistry of Borate in Salt Lake Brine ⅩⅫ. A Studying on Thermal Decomposition of Mineral Ulexite

通过对小柴旦天然沉积钠硼解石矿物(Na_2O·2CaO·5B_2O_3·16H_2O)的热分析研究确定了热脱水反应的阶段、温度和产物,并由DTA、TG、DTG和DSC确定了钠硼解石脱水、重结晶和熔融的温度,给出了脱水过程的热化学反应方程式及各个脱水阶段产物的X—ray粉末衍射和红外光谱结果。

Thermal decomposition of mineral ulexite(Na_2O·2CaO·5B_2O_3·16H_2O), which was taken from Xiao chaidan salt lake, Qinghai Province, has been studied by chemical analysis, thermal analysis (DTA, TG, DTG and DSC), infrared spetra and X—ray powder diffraction. The temperature of various dehydration stages, phase transition and melt point during heating have been determined. The dehydrated mid-products and final products have been identified. At last, the thermochemical reactions of the various dehydration stages, transit reaction and crystallization reaction of melt liquid during cooling have been given.