第18卷第1期 2018年2月
过程与工艺
过程工程学报
The Chinese Journal of Process Engineering
Vol.18 No.1 Feb.2018
D0I: 10.12034/j.issn.1009-606X.217153
Sodium/PotassiumPrecipitationBehaviorduringEvaporativeCrystallizationofAmmonium
ParatungstatefromAmmoniumTungstate/NitrateSolution QiushengZHOU', Dong LI,ZhichengZHU,XiaobinLI, TianguiQI
(SchoolofMetallurgy andEnvironment,Central South University,Changsha,Hunan 410083,China)
Abstract: The effects of several factors, including the amount of ammonium nitrate added, mass ratio of sodium/potassium to tungsten, and reaction temperature, on the precipitation of sodium/potassium during evaporative crystallization of ammonium paratungstate from ammonium tungstate/ammonium nitrate solution system were investigated. The results showed that sodium/potassium paratungstate was precipitated more readily than ammonium paratungstate (APT). Further, the precipitation of sodium/potassium can be inhibited by adding aaaoeoeeseednoeoeesnno ammonium nitrate on the precipitation of sodium/potassium increases with the increase of ammonium nitrate concentration. The sodium/potassium content in the precipitate decrease with a increases of crystallization temperature and an decrease of sodium/potassium content in the solution. The sodium/potassium content in APT can be less than the recommended limit when concentration of ammonium nitrate is 20 g/L, concentration of initial sodium was 0.100 g/L, initial concentration of potassium was 0.030 g/L, and crystallization temperaturewas95C.
Keywords:ammonium paratungstate;tungstenmetallurgy;precipitation;crystallization
CLC No.: TF803.25
Document Code: A
Article ID: 1009606X(2018)01011808
钨酸铵-硝酸铵溶液体系结晶制备仲钨酸铵过程中钠/钾的析出行为
周秋生，
李栋，朱志成，李小斌，齐天贵(中南大学冶金与环境学院，湖南长沙410083)
摘要：研究了在钨酸铵-硝酸铵溶液体系制备仲钨酸铵过程中，硝酸铵添加量、杂钨比、反应温度等因素对钠/钾析出的影响结果表明，仲钨酸钠/钾比仲钨酸铵更易沉淀，且仲钨酸钾最易沉淀.添加硝酸铵可有效抑制钠/钾沉淀，且抑制作用随硝酸铵浓度增加而增大.随温度升高和钠/钾含量降低，析出物中钠/钾含量降低.在硝酸铵添加量20g/L、初始钠含量0.100g/L、初始钾含
量0.030g/L、反应温度95℃的条件下反应，产品中的钠/钾含量能达到国家标准关键词：仲钨酸铵：钨冶金：析出：结晶
1
INTRODUCTION
[APT,
Ammonium
paratungstate
(NH4)1oH2W12042'nH20, n=4, 6, 10) is an important intermediate compound for producing pure tungsten
metallurgy(1-3] and
through
tungsten
exhibits
low
solubility in water and high solubility in ammonium hydroxide[4,5], Currently, the most advanced technique for the commercial production of APT is evaporative crystallization[6],
There are strictlimits
forthe
downstream products of tungsten metallurgy with respect to the chemical purity of APT. This is because impurities such as P, As, Si, Sn, and Mo in the form of anions as well as K, Na, Ca, and Mg in the form of cations readily precipitate in the aqueous solution of ammonium tungstate(AT)[7-9) in amounts that exceed the recommended limit for APT. A studyl10) have shown that the WO concentration, impurity concentration, and crystallization temperature of the starting solution have a marked effect on the precipitation of these impurities.
Received date: 20170301; Accepted date: 20170519
Foundation item: Supported by National Natural Science Foundation of China (No. 51274243); Innovation-driven Plan in Central South University
(No. 2015cx001)
Biography: Qiusheng ZHOU(1972), male, native of Lianyuan City, Hunan Province, PhD, Professor, engaged in metallurgical engineering, Tel: 0731-88830453,
E-mail: qszhou@csu.edu.cn.
引用格式: Zhou Q S, Li D, Zhu Z C, et al. Sodium/Potassium Precipitation Behavior during Evaporative Crystallization of Ammonium Paratungstate from
Ammonium Tungstate/Nitrate Solution. Chin. J. Process Eng-, 2018, 18(1): 118125, DOI: 10.12034/jissn.1009-606X.217153.
万方数据