制备工艺对钯粉粒径的影响

Influence of Preparation Process on Palladium Powder Particle Size

探讨了利用液相还原法,以水合肼为还原剂,制备大颗粒钯粉,应用单变量对比试验的方法讨论了Pd2+浓度、温度、pH值对钯颗粒形核和生长过程的影响,这些因素的影响决定了钯颗粒粒度大小和服役性能。经分析和讨论,得出参数Pd2+浓度为0.1 mol·L-1,pH值为12,温度为50℃是最佳工艺参数的结论,并在此参数下制备出较大粒径的钯粉,且利用SEM,XRD,马尔文激光粒度仪、氮吸附等对其进行表面微观形貌、成分、粒度分布和比表面积等性能进行了分析,较有力地说明这种钯粉具有纯度高、比表面积大等优点,能够满足现排代服役条件的要求,对实际工业生产具有一定的指导意义。

The preparation process of large-particle palladium powders with the liquid-phase reduction method by hydrazine hydrate for reducing agent was discussed.The effects of process parameters,for example the Pd2＋ concentration,temperature and pH value,which regulated the granularity and service performance of palladium particle,on the nucleation and growth of powder were analyzed.It was concluded that optimal processing parameters were 0.1 mol · L-1 Pd2＋,pH=12 and 50 ℃ to obtain large particle Pd powers,and large-particle palladium powders were characterized by the X-ray diffraction（XRD）,scanning electron microscopy（SEM） and surface area measurement,which explained powerfully that the palladium powder had high purity,larger specific surface area,etc,and could meet the service condition,which had certain directive significance to the requirements of the actual industrial production.