摘要
传统铬盐行业生产过程中铬的价态需经过三价到六价再到三价的转化。六价铬的高毒性导致铬成为国家重点防控的重金属。铬盐行业的可持续发展亟需开发避免六价铬产生的新技术,含铬原料的酸浸为可行的途径。本文提出以高碳铬铁合金为原料,盐酸为浸出剂的酸性浸出制备三价铬盐新工艺。浸出后的氯化铬和氯化亚铁可制备出三价铬盐产品,其可作为铁铬液流电池的电解液。本文在对高碳铬铁元素含量、物相组成及形貌等分析的基础上,系统研究了反应温度、盐酸浓度、搅拌速率和反应时间对铬和铁浸出率的影响规律。结果表明,在反应温度100℃、盐酸浓度9mol/L、搅拌速率250r/min、反应时间6h的条件下,铬浸出率为92%,铁浸出率为95%。进一步研究了高碳铬铁在盐酸中浸出的动力学。高碳铬铁的浸出过程符合未反应收缩核模型,铬浸出过程受化学反应控制,表观活化能E_(a)=65.95kJ/mol;铁浸出过程受化学反应控制,表观活化能E_(a)=63.85kJ/mol。
The valence state of chromium in the production process of traditional chromium salt industry needs to go through the transformation of trivalent to hexavalent and then to trivalent.The high toxicity of hexavalent chromium has led to chromium becoming a key heavy metal for national prevention and control.The sustainable development of chromium salt industry urgently requires the development of new technologies to avoid hexavalent chromium generation,and acid leaching of chromium-containing raw materials is a feasible way.In this paper,we proposed a new process for the preparation of trivalent chromium salts by acid leaching using high-carbon ferrochrome alloy as raw material and hydrochloric acid as leaching agent.The leached chromium chloride and ferrous chloride could be prepared as trivalent chromium salt products,which can be used as electrolyte for ferrochrome liquid flow battery.In this paper,the effect of reaction temperature,hydrochloric acid concentration,stirring rate and reaction time on the leaching rate of chromium and iron was systematically studied based on the analysis of elemental content,physical phase composition and morphology of high-carbon ferrochrome.The results showed that the chromium leaching rate was 92%and the iron leaching rate was 95%at a reaction temperature of 100℃,a hydrochloric acid concentration of 9mol/L,a stirring rate of 250r/min and a reaction time of 6h.The kinetics of the leaching of high-carbon ferrochrome in hydrochloric acid was further investigated.The leaching process of high-carbon ferric chromium was consistent with the unreacted contraction nucleation model,and the chromium leaching process was controlled by the chemical reaction with apparent activation energy E_(a)=65.95kJ/mol.The iron leaching process was controlled by the chemical reaction with apparent activation energy E_(a)=63.85kJ/mol.
作者
汪鹏
张洋
范兵强
何登波
申长帅
张贺东
郑诗礼
邹兴
WANG Peng;ZHANG Yang;FAN Bingqiang;HE Dengbo;SHEN Changshuai;ZHANG Hedong;ZHENG Shili;ZOU Xing(School of Metallurgy and Ecological Engineering,Beijing University of Science and Technology,Beijing 100083,China;Key Laboratory of Green Process and Engineering,National Engineering Research Center of Green Recycling for Strategic Metal Resources,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China;Zhengzhou Institute of Emerging Industrial Technology,Zhengzhou 450003,Henan,China)
出处
《化工进展》
EI
CAS
CSCD
北大核心
2023年第S01期510-517,共8页
Chemical Industry and Engineering Progress
关键词
浸出
高碳铬铁
盐酸
动力学
氯化铬
leaching
high-carbon ferrochrome
hydrochloric acid
kinetics
chromium chloride
