Alkaline batteries have been used for more than fifty years and are currently commonly used indifferent portable storage devices. The spent batteries are classified as hazardous because of theirpotential threat to the environment and human health. However, there is no traceability of this wastein most third world countries. In the particular case of Chile, the application of the law 20.920, forcesto find sustainable treatment alternatives for these secondary sources of metallic values. Therefore, itis proposed the use of a mixture of sulfuric acid and hydrogen peroxide as the leaching reagent forzinc and manganese. The effects of metallurgical parameters such as sulfuric acid and hydrogenperoxide concentration were investigated.Alkaline batteries were collected and dismantled manually. The cathodic and anodic electrodematerial obtained was dried at 100 °C for 24 h and subsequently classified into different size fractions.After that, the material was washed in distilled water to remove the remaining potassium hydroxide.The leaching test was carried out in stirred flask at 60°C, 200 rpm and 2 h of leaching time. The resultsindicate that it is possible to achieve zinc extractions greater than 90 % independent of the acid dosageused. However, it is corroborated that the use of a reducing agent and temperature is necessary todissolve the manganese present in the sample. Improvements in manganese extractions are evidentwhen using a concentration of hydrogen peroxide of 10 vol. The best zinc and manganese extractionswere 99.8 % and 43 % respectively at 2M of sulfuric acid concentration and 10 vol % of hydrogenperoxide.
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