常压碳热还原铁酸锌的分解机理及动力学
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摘要
研究了铁酸锌碳热还原的分解机理及动力学。反应机理研究表明:当溫度达到650℃时,铁酸锌首先分解为Fe_3O_4和ZnO;当溫度到达850℃时,铁酸锌的还原产物中出现FeO,当溫度达到950℃时,铁酸锌完全被还原为单质铁。在650℃～850℃溫度范围内,随着温度的升高,分解率升高。在800℃、ω_c/ω_(ZnFe_2O_4)=1/4、还原时间为80 min时,铁酸锌的分解率到达94%。动力学计算表明:铁酸锌的碳热还原分解过程受化学反应控制,表观活化能为24.65 kJ/mol。
The decomposition mechanisms and kinetics of zinc ferrite by carbonthermal reduction is investigated.The study on reaction mechanisms shows that zinc ferrite is firstly decomposed into Fe304 and ZnO at 650 ℃, and FeO is generated as the temperature is further increased to 850 ℃. However, the zinc ferrite is reduced to iron completely at 950 ℃. Meanwhile, the reducing rate of zinc ferrite is obviously increased with the reaction temperature increasing from 650 ℃ to 850 ℃. At the conditions of 800 ℃, t = 80 min, the decomposition rate of zinc ferrite reaches 94%. The kinetics calculation indicates that the carbonthermal reduction and decomposition process of zinc ferrite is controlled by chemical reaction, and its apparent activation energy is 24. 65 kJ/mol.
The decomposition mechanisms and kinetics of zinc ferrite by carbonthermal reduction is investigated.The study on reaction mechanisms shows that zinc ferrite is firstly decomposed into Fe304 and ZnO at 650 ℃, and FeO is generated as the temperature is further increased to 850 ℃. However, the zinc ferrite is reduced to iron completely at 950 ℃. Meanwhile, the reducing rate of zinc ferrite is obviously increased with the reaction temperature increasing from 650 ℃ to 850 ℃. At the conditions of 800 ℃, t = 80 min, the decomposition rate of zinc ferrite reaches 94%. The kinetics calculation indicates that the carbonthermal reduction and decomposition process of zinc ferrite is controlled by chemical reaction, and its apparent activation energy is 24. 65 kJ/mol.
引文
[1]解立群,施哲,胡汉等.铁酸锌还原焙烧试验研究[J].矿冶,2011,20(3):76-78.
[2]窦明民.锌冶金中铁酸锌生成及离解机理研究[J].云南冶金,2003,32(10):63-65.
[3]刘洋,谭军,尹周澜等.湿法炼锌沉铁渣和浸锌渣的焙烧预处理[J].中国有色金属学报,2016,16(1):212-222.
[4]许冬,阮胜寿,贾荣.锌冶炼废渣中铟的回收技术概述[J].材料研究与应用,2009,3(4):231-233.
[5]王欣,杨大锦,彭金辉,巨少华.微波加热配碳还原分解铁酸锌的工艺及机理研究[J].有色金属(冶炼部分),2013,(5):1-5.
[6]陈栋,彭兵,柴立元等.铁酸锌选择性还原方法及其在锌焙砂处理中的应用[J].中国有色金属学报,2015,25(8):2284-2292.
[7]王纪明,彭兵,柴立元,李密,彭宁.锌浸渣还原焙烧-磁选回收铁[J].中国有色金属学报,2012,22(5):1455-1461.
[8]闫缓.基于铁酸锌选择性还原的锌浸出渣处理研究[D].长沙:中南大学,2014.
[9]Tong L F.Reduction mechanisms and behavior of zinc ferritePart 1:pure ZnFe_2O_4[J].Transactions of the Institution of Mining and Metallurgy Section C-Mineral Processing and Extractive Metallurgy,2001,110(1):14-24.
[10]侯栋科,彭兵,柴立元,彭宁,闫缓.铁酸锌选择性还原的反应机理[J].中国有色金属学报,2014,24(10):2634-2641.
[11]李密.锌焙砂选择性还原与铁锌分离的基础研究[D].长沙:中南大学,2013.
[12]陈少纯,周令治,邹家炎,田润苍.铁酸锌的还原分解和其中锗的行为[J].广东有色金属学报,1991,1(1):26-31.
[2]窦明民.锌冶金中铁酸锌生成及离解机理研究[J].云南冶金,2003,32(10):63-65.
[3]刘洋,谭军,尹周澜等.湿法炼锌沉铁渣和浸锌渣的焙烧预处理[J].中国有色金属学报,2016,16(1):212-222.
[4]许冬,阮胜寿,贾荣.锌冶炼废渣中铟的回收技术概述[J].材料研究与应用,2009,3(4):231-233.
[5]王欣,杨大锦,彭金辉,巨少华.微波加热配碳还原分解铁酸锌的工艺及机理研究[J].有色金属(冶炼部分),2013,(5):1-5.
[6]陈栋,彭兵,柴立元等.铁酸锌选择性还原方法及其在锌焙砂处理中的应用[J].中国有色金属学报,2015,25(8):2284-2292.
[7]王纪明,彭兵,柴立元,李密,彭宁.锌浸渣还原焙烧-磁选回收铁[J].中国有色金属学报,2012,22(5):1455-1461.
[8]闫缓.基于铁酸锌选择性还原的锌浸出渣处理研究[D].长沙:中南大学,2014.
[9]Tong L F.Reduction mechanisms and behavior of zinc ferritePart 1:pure ZnFe_2O_4[J].Transactions of the Institution of Mining and Metallurgy Section C-Mineral Processing and Extractive Metallurgy,2001,110(1):14-24.
[10]侯栋科,彭兵,柴立元,彭宁,闫缓.铁酸锌选择性还原的反应机理[J].中国有色金属学报,2014,24(10):2634-2641.
[11]李密.锌焙砂选择性还原与铁锌分离的基础研究[D].长沙:中南大学,2013.
[12]陈少纯,周令治,邹家炎,田润苍.铁酸锌的还原分解和其中锗的行为[J].广东有色金属学报,1991,1(1):26-31.