Lead production from recycled paste of lead acid batteries with SiC-Na2CO3

Resumo

A novel pyrometallurgical route was used to reduce the lead paste to obtain metallic lead with different additions of sodium carbonate at 850°C in a silicon carbide crucible. The process allows to obtain a high recovery of metallic lead in a single step and a slag constituted mainly by lead silicate. Products obtained were characterized by atomic absorption, X-ray powder diffraction and SEM-EDS techniques. A thermodynamic study was carried out with the software FactSage to determinate the compounds formation to the experimental conditions. High amounts of Na₂CO₃ and SiC promoted the formation of a lead sulfide compound which decreased the lead recovery.