矿产保护与利用Issue(5)：49-53,5.DOI:10.13779/j.cnki.issn1001-0076.2017.05.010
固阳褐铁矿脱水反应动力学研究
Study on the Dehydration Reaction Kinetics of Guyang Limonite
摘要
Abstract
The reaction mechanism of dehydration process of Guyang limonite was studied by TG -DTA and X-ray diffraction .The thermal analysis data were processed and analyzed by the liner correlation calculation with different dynamic mechanism models .The dehydration reaction mecha-nism was determined , meanwhile , the kinetic parameters of dehydration reaction were calculated by Coat-Redfern integral method .The results showed that the dehydration reaction process of Guyang limonite is divided into two stages .The first stage is at 140 ~320 ℃ with a weight loss rate of 4.78%and a reaction activation energy of 28.54 kJ/mol.The reaction mechanism of the first stage is in accordance with Avrami -Erofeev equation , which belongs to the stoichiometric and subsequent growth of the primary chemical reaction .While the second stage is at 320~465 ℃ with a weight loss rate of 3.84%and a reaction activation energy of 61.92 kJ/mol.The reaction mechanism of the second stage agrees with the secondary reaction function , and it is controlled by chemical reac-tions.XRD results showed that the phase transition of limonite occurs at 200 ℃ with increasing temperature , during which the diffraction peaks of goethite are weakening and disappearing , but the diffraction peaks of hematite gradually increase .As a result , the mineral phases become pure .关键词
褐铁矿/热重分析/活化能/脱水动力学Key words
limonitic/thermogravimetric analysis/activation energy/dehydration kinetics分类
化学化工引用本文复制引用
王建英,张新龙,张铁柱..固阳褐铁矿脱水反应动力学研究[J].矿产保护与利用,2017,(5):49-53,5.基金项目
内蒙古自治区科技重大专项项目(200500201) （200500201）
