Method for separating tin from waste tinplate and preparing tin dioxide

• Main Authors: LIN XINGZHANG, TANG HONGHUI, LIU GENGHAO, TAN JINGJIN, LI ZHANGDONG
• Format: Patent
• Language: Chinese; English
• Published: 22.06.2011
• Subjects: CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION ORPROCESSING OF GOODS; FERROUS OR NON-FERROUS ALLOYS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; METALLURGY; PRETREATMENT OF RAW MATERIALS; PRODUCTION AND REFINING OF METALS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; TREATMENT OF ALLOYS OR NON-FERROUS METALS

The invention discloses a method for separating tin from waste tinplate and preparing tin dioxide. The method comprises the following steps: (1) grinding waste tinplate, screening; (2) washing the screen underflow with soda water; (3) filtering the washed material, leaching filter residue with sodium hydroxide solution and oxidant, filtering the leachate, wherein the filtrate is sodium stannate solution; and (4) introducing carbon dioxide in the sodium stannate solution, filtering, and washing to obtain the tin dioxide product. The preparation method of the invention has low cost and pollution and remarkable economic value and market competition.