电解工艺参数对铟微粉纯度和粒度的影响(II)

Effect of Electrolytic Process Parameters on the Purity andParticle Size of Indium Powder (II)

摘要:

研究了电解工艺制备铟微粉时,电解温度、极距、导电盐浓度、电解液pH、添加剂种类对粉体纯度和粒度的影响。结果表明：电解最佳工艺参数为In₃₊浓度为30g/L,电流密度为130 A/cm₂,连续电解时间为1h,NaCl浓度80g/L,极距5cm,硫脲浓度0.3g/L,明胶浓度0.5g/L,pH=2.5,聚乙烯吡咯烷酮用量为0.2g/L。在此工艺条件下电解,极距的大小,基本不影响粉体的纯度,但对粉体的粒度影响较大；NaCl浓度对粉体纯度影响最大；电解液温度越高,所得粉体粒度变大,粉体纯度降低；电解液的pH既影响粉体的纯度,又影响粉体的粒度；添加剂硫脲对粉体的枝晶生长有抑制作用。在此工艺参数下电解1h,可得到粒度小于100μm的铟微粉,其中粒度小于30μm的占75%,粉体纯度为99.98%,平均电流效率达70.10%。

Abstract:

_{:The effect of temperature, the distance of electrodes, conductive salt concentration, pH values and kinds of additives on the purity and size of indium powder by electrolysis process was studied. The results show that：The optimum process parameters for electrolysis are obtained. (The optimum process parameters for electrolysis as follows: The concentration of In3+ is 30g/L, the current density is 130 A/cm2, continuous electrolysis time is 1 hour, the concentration of NaCl is 80g/L, the distance of electrodes is 5cm, thiourea concentration is 0.3g/L, gelatin concentration is 0.5g/L, pH=2.5 and polyvinylpyrrolidone is 0.2g/L). Under these conditions, the distance of electrodees does not affect the purity of the powder, but affect theparticle size of the powder. The concentration of NaCl has the greatest influence on the purity of the powder.The higher temperature of the electrolyte, the particle size becomes larger and the purity of the powder decreases. The additive of thiourea restraining dendrite growth of the powder. Electrolysis 1 hour under the optimum process parameters, indium powder with a grain size of less than 100μm is obtained. The particle size less than 30μm accounted for 75%, the purity of the powder is 99.98%, and the average current efficiency is 70.10%.}