碳辅助氢还原制备纳米钨粉的工艺及机理

发布时间：2018-03-28 16:24

  本文选题：纳米W粉　切入点：碳辅助氢还原　出处：《中国有色金属学报》2016年05期

【摘要】：以偏钨酸铵和葡萄糖为原料,采用碳辅助氢气还原的方法制备出纳米W粉,并研究W、C摩尔比和还原工艺对W粉的平均粒度和残碳量的影响。结果表明:还原产物、W粉的平均粒度和残C量与还原温度和W、C摩尔比密切相关,而当还原时间超过1 h后,还原时间对W粉的平均粒度和残C量没有明显的影响。还原产物决定于还原温度,W、C摩尔比为1:2.6的前驱体在700、750、800℃还原以后得到的产物分别为W+WO_2、W+W_2C+WC和W。W粉的粒度随着W、C摩尔比由1:2.0增加到1:3.0而由98 nm减小到42 nm,但W粉的残C量在W、C摩尔比小于1:2.6时都在0.05%(质量分数)以下,W、C摩尔比继续增加时,W粉的残C量显著增加。W、C摩尔比为1:2.6的原料经800℃还原1 h后得到无明显团聚的W粉,其平均粒度为46 nm,残C量为0.05%(质量分数)。
[Abstract]:Using ammonium metatungstate and glucose as raw materials, nanocrystalline W powder was prepared by carbon-assisted hydrogen reduction. The effects of W / C molar ratio and reduction process on the average particle size and residual carbon content of W powder were studied. The results showed that the average particle size and residual C content of W powder were closely related to the reduction temperature and the molar ratio of W / C, and when the reduction time was more than 1 h, the reduction time was more than 1 h. The reduction time has no significant effect on the average particle size and residual C content of W powder. The reduction product is determined by the particle size of W WO 2W W 2C WC and W W W 2C WC after reduction at 700750800 鈩，

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