复盐法制备无水氯化镁的热解机理及动力学研究

Mechanisms and Kinetics for Preparation of Anhydrous Magnesium Chloride by Complex Thermal Decomposition Method

The complex compound (MgCl2·C6H5NH2·HCl·6H2O) was prepared by reaction of C6H5NH2·HCl with MgCl2·6H2O. Reaction mechanism and kinetics of the compounds decomposition were studied by means of the TG-DTA-MS coupling technique and the TG-DTA technique. The results show that there are four steps in the complex′s thermal decomposition, the first two steps correspond to the loss of six crystal waters and the last two steps loss one Aniline hydrochloride. The first three steps belong to the R2 mechanism with 2-dimentional phase boundary reaction as the control step, and the last step belongs to the D3 with 3-dimensional diffusion (sphere Jander equ.) as the control step. The apparent active energy of four steps are, 127.4 kJ·mol-1, 124.8 kJ·mol-1, 142.3 kJ·mol-1 and 329.0 kJ·mol-1, respectively and the frequency factor are 1.28 × 1018 s-1, 7.94 × 1015 s-1, 5.98 × 1016 s-1 and 4.39 × 1034 s-1, respectively.

The complex compound （MgCl2·C6H5NH2·HCl·6H2O） was prepared by reaction of C6H5NH2·HCl with MgC12-6H2O. Reaction mechanism and kinetics of the compounds decomposition were studied by means of the TG-DTA-MS coupling technique and the TG-DTA technique. The results show that there are four steps in the complex＇s thermal decomposition, the first two steps correspond to the loss of six crystal waters and the last two steps loss one Aniline hydrochloride. The first three steps belong to the R2 mechanism with 2-dimentional phase boundary reaction as the control step, and the last step belongs to the D3 with 3-dimensional diffusion （sphere Jander equ.） as the control step. The apparent active energy of four steps are, 127.4 kJ·mol^-1, 124.8 kJ·mol^1, 142.3 kJ·mol^1 and 329.0 kJ·mol^1, respectively and the frequency factor are 1.28 × 10^18 s^-1, 7.94 × 10^15 s^-1, 5.98 × 10^16 s^-1 and 4.39 × 10^34 s^-1, respectively.