中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 24 No. 6 June 2014 |
（1. National Engineering Laboratory for Vacuum Metallurgy,
Kunming University of Science and Technology, Kunming 650093, China;
2. State Key Laboratory of Complex Nonferrous Metals Resources Clear Utilization,
Kunming University of Science and Technology, Kunming 650093, China）
Abstract:A novel technique was developed to remove impurities from crude lead by vacuum distillation. The thermodynamics on vacuum distillation refining process of crude lead was studied by means of saturated vapor pressure of main components of crude lead, separation coefficients and vapor-liquid equilibrium composition of Pb-i (i stands for an impurity) system at different temperatures. The behaviors of impurities in the vacuum distillation refining process were investigated. The results show that the vacuum distillation should be taken to obtain lead from crude lead, in which Zn, As and partial Sb are volatilized at lower temperature of 923-1023 K. Lead is distilled from the residue containing Cu, Sn, Ag and Bi at higher temperature of 1323-1423 K, but the impurity Bi is also volatilized along with lead and cannot be separated from lead.
Key words: crude lead; vacuum distillation; refining; removal; thermodynamics
