高浓度Bi^(3+)离子对Cu电解精炼中阴极过程的影响

EFFECT OF- HIGH CONCENTRATION Bi^(3+) ON CATHODIC PROCESS OF COPPER ELECTROREFINING

采用线性电位扫描法、循环伏安法、电导测定及ＸＲＤ，ＸＰＳ法等研究了高浓度Ｂｉ３＋离子存在于酸性ＣｕＳＯ４电解液中对Ｃｕ电解精炼阴极过程的影响．研究表明：Ｂｉ３＋离子的存在减小了电解液的电导率，降低了阴极Ｃｕ沉积反应的交换电流密度、极限电流密度和峰电流密度，对Ｃｕ沉积反应起极化作用、在通常电流密度２００ Ａ·ｍ－２下电解，Ｂｉ不会在阴极沉积，但促使Ｃｕ沉积的晶面２２０择优取向更加突出．在高电流密度１０００ Ａ·ｍ－２下电解，Ｂｉ以Ｂｉ２Ｏ３形式存在于沉积层中，Ｃｕ沉积的晶面择优取向为１１１．

The effect of high concentration Bi3+ on the cathodic process of copper electrorefin- ing in acidified CuSO4 electrolyte was studied by linear potential sweep method, cyclic voltammetry method, XRD, XPS and conductivity measurements. The results indicate that high concentration Bi3+ could decrease the conductivity of the electrolyte, the exchange current density, the limiting current density and peak current density of copper deposition reaction, so that Bi3+ has an action of polarization on the reaction of copper deposition. When electrolysis was carried out at 200 A·m-2, Bi did not deposit on the cathode, bat made the growth of the preferred orientation 220 of copper crystal more easily.While electrolysis at 1000 A.m-2, Bi existed on the cathode layer in the form of Bi2O3, and Cu 111 crystal face grew preferentially.