共查询到19条相似文献,搜索用时 78 毫秒
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用钨细泥制取钨酸钠和仲钨酸铵新工艺研究 总被引:1,自引:0,他引:1
研究了用高钙、高杂质钨细泥制备高纯钨酸钠和仲钨酸铵的新工艺,试验证明,采用碱法热球磨分解技术和离子交换除钼的新工艺,可保证在低碱耗下钨的平均分解率达96.92%以上,分解得到的钨酸钠溶液中杂质磷、砷、硅含量接近经典法处理钨精矿的水平。将粗钨酸钠溶液一次蒸发结晶后用离子交换法除钼。再经二次蒸发结晶可得到高纯钨酸钠。一次蒸发结晶后的钨酸钠溶液经离子交换转型为钨酸铵溶液后再经离子交换法除钼,可得到高纯仲钨酸铵。本工艺具有流程短、回收率高,对环境无不利影响等特点,有明显的经济效益和社会效益。 相似文献
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《稀有金属与硬质合金》2016,(3)
采用溶解平衡法研究了(NH_4)_2HPO_4-H_2O系仲钨酸铵(APT)的溶解性能。结果表明:当温度低于70℃时,仲钨酸铵的溶解度随磷酸氢二铵浓度的升高而减小;当温度达到70℃以上时,仲钨酸铵的溶解度随磷酸氢二铵浓度的升高而增大。在高温下磷钨杂多酸的形成是仲钨酸铵溶解性能和溶解速率大幅提高的主要原因。 相似文献
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本文介绍了一种仲钨酸铵的生产方法:将六甲撑四胺加入初次的钨酸铵溶液,用酸调整pH值到2左右,便生成一种主要含钨和六甲撑四胺的沉淀物。把这种沉淀物与母液分离后再溶解在氨水中,便得到二次的钨酸铵溶液,在90—100℃下加热此溶液,即生成基本上全是仲钨酸铵的沉淀物和基本上全是六甲撑四胺的母液,然后使仲钨酸铵沉淀与母液分离。 相似文献
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韩曙祥 《有色金属(冶炼部分)》1993,(3):34-37,40
对影响仲钨酸铵结晶的粒度、粒度分布及其形貌等物性生成条件的工艺参数进行了较系统的研究,在此基础上提出了制取各粒级仲钨酸铵的工艺条件,并进行了验证试验。文中还提出了用两种不同的气体搅拌制取APT粗粒和细粒新方法的试验情况。 相似文献
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仲钨酸铵(APT)主要采用蒸发钨酸铵溶液的方式制取,是钨冶炼中最重要的中间产品,其化学质量将直接影响后续钨产品的质量.以硫磷混酸协同分解白钨所得钨酸铵溶液为原料,通过研究APT蒸发结晶过程中主要杂质离子的析出规律,获得了制备APT-0级产品所要满足的钨酸铵原料液中各杂质的浓度上限,既为钨酸铵净化工序提供了除杂深度的数据... 相似文献
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采用添加碱性浓钨酸钠料液转化-镁盐沉淀深度脱氨工艺,使仲钨酸铵结晶母液脱除氨氮.研究结果表明,经此处理溶液中的氨氮含量可除至0.042 g/L,氨氮的除去率达98.88%.将所得钨酸钠溶液稀释10倍用于配制交前液进行离子交换,交后液中的氨氮浓度小于0.0005%,可达国家排放标准. 相似文献
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《Hydrometallurgy》2007,85(2-4):67-71
Ammonium paratungstate was prepared from tungsten alloy swarf employing anodic dissolution in sodium hydroxide using a packed bed configuration followed by chemical conversion into ammonium tungstate through tungstic acid. The alkaline tungstate solution was dialysed to recover sodium hydroxide, which could be recycled to the electrolytic dissolution. The influence of anodic current density and other parameters on dissolution/recovery was studied and discussed. It was observed that a current density of 600 mA/100 g scrap could be applied when the concentration of NaOH was maintained around 2.5 M. The energy consumption for anodic dissolution was 2.14 kWh/kg W with more than 90% recovery achieved. XRD studies indicated that the exhausted scrap contained an alloy of nickel and iron with a very low percentage of tungsten. APT sample prepared through anodic dissolution in NaOH was characterized. 相似文献
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Scheelite could be digested with an aqueous diammonium phosphate and ammonia solution in an autoclave. However, unexpected ammonium paratungstate (APT) crystallisation and tungstophosphoric acid formation occasionally occurred. In order to provide a theoretical basis for the scheelite leaching process, the solubility of APT in solution was determined by the isothermal solution equilibrium method. The effects of initial ammonia and diammonium phosphate concentration as well as temperature on APT solubility and tungstophosphoric acid formation were investigated. Results showed that APT solubility increased with increasing ammonia concentration, diammonium phosphate concentration and temperature, while tungstophosphoric acid concentration in the leaching solution increased with decreasing ammonia concentration and increasing diammonium phosphate concentration. In order to verify the effects of these factors on the leaching of scheelite, scheelite digestion experiments using diammonium phosphate and ammonia solution were also carried out. 相似文献