Abstract:A new green process of low-temperature, low discharge of carbon dioxide, no emission of sulfur oxide, clean and environment friendly smelting of secondary lead was proposed. In the process, with lead-bearing secondary zinc oxide dusts as sulfur-fixing agent and coke powders as reducing agent, spent lead-acid battery colloid sludge was reduced into crude lead and zinc was recovered as standard or marketable zinc sulfide concentrates in the molten salt of Na2CO3 at 800~900 ℃. The effects of smelting temperature, dosage of sodium carbonate, zinc oxide and coke powders on lead recovery and sulfur-fixing rate were investigated based on thermodynamic analysis. The results show that direct recovery and total recovery of lead is 96.64% and 98.06% respectively and sulfur-fixing rate is 94.70% under the optimum conditions including mass ratio of sodium carbonate and solid of 2.84, dosage of zinc oxide of 1.1 times of theoretical value, mass ratio of coke powders and colloid sludge of 16%, and temperature of 880 ℃.