水热合成钨前驱体-碳热还原-碳化制备超细纳米级碳化钨
Preparation of Ultrafine Nanosized Tungsten Carbide by Hydrothermal Synthesis of Tungsten Precursor,Carbother-mic Reduction,and Carburization
李江涛 1罗勇进 2苏准 3赵中伟 1陈爱良 2刘旭恒 2何利华 1孙丰龙 2陈星宇1
作者信息
- 1. 中南大学冶金与环境学院,湖南长沙 410083;稀有金属冶金与材料制备湖南省重点实验室,湖南长沙 410083
- 2. 中南大学冶金与环境学院,湖南长沙 410083
- 3. 中南大学冶金与环境学院,湖南长沙 410083;上海交通大学材料科学与工程学院,上海 200240
- 折叠
摘要
提出了一种以水热合成的PbWO4为原料,然后通过碳热还原-碳化获得超细WC的方法.以PbWO4为钨中间产品,避免了氨氮试剂的引入;采用碳还原的方式可避免水蒸气的产生,抑制了钨粉的长大.结果表明:在初始pH为7.0、反应温度为160 ℃,反应时间为4.5h的条件下,Na2WO4溶液中99.9％(质量分数)以上的W以PbWO4的形式回收.然后采用低温碳还原PbWO4,在C∶W摩尔比为5、950 ℃的条件下还原3 h,获得了 W和C的混合物,该混合物中预加富余的C有助于抑制钨粉的团聚.然后将W和C混合物高温碳化,在1200 ℃下反应6h,获得了粒径约为60 nm的WC粉末.
Abstract
A novel method to prepare ultrafine WC was proposed:the PbWO4 prepared by hydrothermal synthesis was used as raw material,and WC was obtained through the carbothermic reduction-carburization process.PbWO4 was used as the tungsten intermediate product to avoid the introduction of ammonia nitrogen reagent.The carbon reduction method can avoid the generation of water vapor and inhibit the growth of tungsten powder.Results show that more than 99.9wt％of W is extracted in the form of PbWO4 from the Na2WO4 solution under the conditions of initial pH value of 7.0,reaction temperature of 160 ℃,and reaction time of 4.5 h.Then,the homogeneous mixture of W and C is obtained by the carbothermic reduction of PbWO4 at 950 ℃ for 3 h with the molar ratio of carbon:tungsten as 5.Pre-adding excessive carbon in the mixture can inhibit the agglomeration of tungsten powder.Subsequ-ently,the WC powder with particle size of about 60 nm is obtained by the carburization of the W and C mixture at 1200 ℃ for 6 h.
关键词
钨酸铅/超细碳化钨/水热处理/还原碳化Key words
PbWO4/ultrafine WC/hydrothermal method/reductive carbonization引用本文复制引用
基金项目
National Natural Science Foundation of China(51334008)
National Key Research and Development Program of China(2022YFC2904505)
Project of Basic Science Center of the National Natural Science Foundation(72088101)
出版年
2024
NETL
NSTL
万方数据