Title:
METHOD OF REGENERATING AND RECOVERING LEAD FROM LEADDSULFATEECONTAINING WASTE PRODUCT
Document Type and Number:
Japanese Patent JPS5493626
Kind Code:
A
Abstract:
A process of regenerating and recovering lead from lead sulphate-containing wastes which comprises (i) contacting the lead battery scrap with an aqueous solution of ammonium carbonate to form lead carbonate and ammonium sulphate, (ii) subjecting the solid phase containing the lead carbonate obtained by solid-liquid separation of the reaction product so formed to roast-reduction at a temperature ranging from about 350 DEG C. to about 700 DEG C. in the presence of a carbon material reducing agent to generate and recover the lead, (iii) double decomposing the liquid phase containing the ammonium sulphate obtained by said solid-liquid separation by the addition of calcium hydroxide in an amount such that the molar ratio of the calcium hydroxide added, expressed as Ca(OH)2/(NH4)2SO4, is about 1.05 to about 1.90 and that the concentration of a calcium sulfate slurry formed as a by-product is about 5 to about 10%, and further contacting ammonium hydroxide thus formed with carbon dioxide gas, to recover ammonium carbonate in a form of an aqueous solution for reuse in said contacting step (i), and (iv) recycling the aqueous ammonium carbonate solution of step (iii) to step (i).
Inventors:
OKUDA MASAAKI
TOMIZAKI KIYOTAKA
TOMIZAKI KIYOTAKA
Application Number:
JP25778A
Publication Date:
July 24, 1979
Filing Date:
January 06, 1978
Export Citation:
Assignee:
DIAMOND ENG CO LTD
International Classes:
C22B13/00; C22B7/00; (IPC1-7): C22B7/00; C22B13/04