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本文采用ＤＴＡ、ＴＧ、ＨＴＸＴＤ和ＴＥＭ研究了ＳｉＯ２包敷α－ＦｅＯＯＨ粒子的脱水过程。从ＤＴＡ和ＴＧ曲线算得的动力学参数表明，ＳｉＯ２包敷α－ＦｅＯＯＨ粒子的脱水过程近似为一级反应，其活化能大于未处理的α－ＦｅＯＯＨ粒子的活化能。ＨＴＸＲＤ和ＴＥＭ的测量结果表明，α－ＦｅＯＯＨ热分解成α－Ｆｅ２Ｏ３同时形成晶核和条形微孔，这可能是Ｘ射线衍射峰展宽的主要原因。随着温度增加，微孔织构转变为中孔或大孔织构，大约在８００℃以上逐渐消失。对于ＳｉＯ２包敷α－ＦｅＯＯＨ，其相应的热变化温度移向高温。
In this paper, DTA, TG, HTXTD and TEM were used to study the dehydration process of SiO2 coated α-FeOOH particles. The kinetic parameters calculated from the DTA and TG curves show that the dehydration process of SiO2-coated α-FeOOH particles is approximately a first order reaction and the activation energy is larger than that of untreated α-FeOOH particles. The measurement results of HTXRD and TEM show that thermal decomposition of α-FeOOH into α-Fe2O3 forms nuclei and strip-shaped micropores, which may be the main reason for the broadening of X-ray diffraction peaks. With the increase of temperature, the microstructure changes into a mesopore or macroporous texture and gradually disappears above about 800 ℃. For SiO2 coated α-FeOOH, the corresponding thermal transition temperature to high temperature.