三氧化二钒的非等温氧压碱溶动力学研究  

Non-Isothermal Dissolution Kinetics of Vanadium Trioxide at High Pressure in Sodium Hydroxide Solution

作　　者：邱爽[1] 魏昶[1] 李旻廷[1] 周雪娇[1] 

机构地区：[1]昆明理工大学冶金与能源工程学院,云南昆明650093

出　　处：《稀有金属》2011年第2期269-275,共7页Chinese Journal of Rare Metals

基　　金：国家自然科学基金(50874053);国家高技术研究发展计划(2009AA06Z106)资助项目

摘　　要：研究了化学纯V2O3在氧压碱浸过程中钒的非等温溶解动力学。考察了搅拌转速(200～1000 r.min-1)、氧分压(200～700 kPa)、NaOH浓度(0.1～2.0 mol.L-1)和升温速率(1.31～4.01 K.min-1)对钒溶解率的影响。实验结果表明,降低升温速率或增大氧气压力,可以提高钒浸出率;搅拌转速在800 r.min-1以上或NaOH浓度高于0.5 mol.L-1时对反应速率的影响可以忽略。采用一种非等温动力学模型来描述该反应过程,得到了4种不同升温速率下碱液浸取提钒的动力学方程式。动力学分析结果显示,在室温与423 K之间,该浸出过程的平均表观活化能E为36.62～37.52 kJ.mol-1。从而证实了在实验条件下,溶解过程的控制步骤为化学反应与扩散混合控制。反应中氧分压和NaOH浓度的反应级数分别为0.74和0。The non-isothermal kinetics of V2O3 dissolution at high pressure in NaOH-O2 system was investigated.The effects of agitation speed（200~1000 r·min-1）,partial pressure of oxygen（200~700 kPa）,initial sodium hydroxide concentration（0.1~2.0 mol·L-1）,and heating rate（1.31~4.01 K·min-1） on vanadium dissolution were determined.Experimental data showed that the higher vanadium dissolution ratio could be obtained by increasing partial pressure of oxygen or decreasing heating rate.Stirring speed over 800 r·min-1 and sodium hydroxide concentration over 0.5 mol·L-1 had very little effect on the dissolution rate.A non-isothermal kinetics model was applied to describe the dissolution of vanadium trioxide,and four kinetic equations for different heating rate were obtained.It was found that the mean apparent activation energy of the kinetics process were 36.62~37.52 kJ·mol-1 between surrounding temperature and 423 K.Among the experimental condition,the dissolution process was controlled by both of the chemical reaction and diffusion.Reaction orders with respect to partial pressure of oxygen and sodium hydroxide concentration were 0.74 and 0,respectively.

关 键 词：三氧化二钒 溶解 压力氧化 氢氧化钠 动力学 

分 类 号：TF841.3[冶金工程—有色金属冶金] TF801.1