无机盐工业
主管:中海油天津化工研究设计院有限公司
主办:中海油天津化工研究设计院有限公司
   中海油炼油化工科学研究院(北京)有限公司
   中国化工学会无机酸碱盐专业委员会
ISSN 1006-4990 CN 12-1069/TQ

无机盐工业 ›› 2020, Vol. 52 ›› Issue (4): 49-52.doi: 10.11962/1006-4990.2019-0306

• 研究与开发 • 上一篇    下一篇

氯化铵结晶过程实验研究

王浩浩,笪涛,叶世超()   

  1. 四川大学化学工程学院,四川成都 610065
  • 收稿日期:2019-10-15 出版日期:2020-04-10 发布日期:2020-04-22
  • 通讯作者: 叶世超
  • 作者简介:王浩浩(1994— ),男,硕士,研究方向为结晶分离操作;E-mail: whh1519816@sina.com。

Experimental study on crystallization process of ammonium chloride

Wang Haohao,Da Tao,Ye Shichao()   

  1. School of Chemical Engineering,Sichuan University,Chengdu 610065,china
  • Received:2019-10-15 Online:2020-04-10 Published:2020-04-22
  • Contact: Ye Shichao

摘要:

在混合悬浮结晶器中研究了氯化铵结晶热力学和动力学特性。以硝酸锰为添加剂,配制了质量分数为0.23%的硝酸锰水溶液,测定了氯化铵在该溶液中的溶解度及超溶解度。研究了硝酸锰对氯化铵晶体粒度分布的影响,得到了晶体变异系数。考察了过饱和度对氯化铵结晶线性生长速率和成核速率的影响,得到了成核-生长动力学方程。结果表明:介稳区宽度随温度升高而减小;添加晶种,介稳区宽度变窄。随硝酸锰溶液浓度增大,晶体变异系数逐渐降低并趋于平缓。当硝酸锰的质量分数逐渐增大到0.307%时,晶体变异系数几乎不再降低。线性生长速率和成核速率随溶液过饱和度的增大而增加,得到的动力学方程与实验数据吻合较好,有一定的工业参考价值。

关键词: 氯化铵, 结晶, 热力学, 动力学, 硝酸锰

Abstract:

The thermodynamic and kinetic properties of ammonium chloride crystallization were investigated in a hybrid sus-pension crystallizer.A manganese nitrate aqueous solution with a mass fraction of 0.23% was prepared by using manganese nitrate as an additive,and the solubility and supersolubility of ammonium chloride in the solution were determined.The effect of manganese nitrate on the particle size distribution of ammonium chloride crystal was studied and the coefficient of variation of crystal was obtained.The effects of supersaturation on the linear growth rate and nucleation rate of ammonium chloride crystal were investigated,and the nucleation-growth kinetics equation was obtained.The results showed that the width of the metastable zone decreased with increasing temperature,and seed crystals were added,and the width of the metastable zone was narrowed.As the concentration of the manganese nitrate solution increased,the coefficient of variation of the crystal grad-ually decreased and tended to be gentle.When the concentration of manganese nitrate was gradually increased to 0.307%,the coefficient of variation of the crystal was hardly reduced.The linear growth rate and nucleation rate increased with the increase of solution supersaturation.The obtained kinetic equation agrees well with the experimental data and has certain industrial reference value.

Key words: ammonium chloride, crystallization, thermodynamics, kinetics, manganese nitrate

中图分类号: