Antimony Removal by Sodium Nitrate in Lead Purification Process

The modified Harris Process which uses sodium carbonate and sodium nitrate is currently being used to remove antimony during the lead purification process in the battery manufacturing process. This study investigates the possibility of using sodium nitrate alone to remove antimony from lead. The process was carried out in a lead-purifying kettle. The optimum temperatures used were in the range of 600 – 650 ˚C. Turnaround time was reduced from 24 hours to 16 hours. Yield was increased from 67% to 78%. The purity of the lead obtained was 99.9% analysed by Atomic Absorption Spectroscopy which is ideal in the battery manufacturing. The results indicate that sodium nitrate can be used alone as a cost-effective method for the removal of antimony.