Recycling manganese from dry battery cathode materials

But due to the dual reasons of management and technical, waste batteries’ pollution control is seriously lagging behind, causing the majority used batteries throw with household waste or landfill everywhere, of which the heavy metals and acid-base and other pollutants through a variety of ways to enter the human food chain. There are still some used batteries with household waste incineration landfill, causing serious pollution to atmosphere.

The battery contains a lot of useful metals. According to relevant statistics, Chinese waste batteries can recycle a considerable number of valuable metals each year, including 109200t manganese powder, 38200t zinc skin, 600t copper, 29600t metal, 2.48t mercury. Waste zinc-manganese dry batteries contain large amounts of unreacted MnO2, and other forms Mn. Manganese not only one of important cathode materials, also have quite a wide range of non-battery applications. In recent years, manganese’s non-battery uses has gradually expanded, in addition to the traditional metallurgical, chemical, metal powder, batteries and other areas, in environmental protection, advanced battery materials, ferrite, ceramic materials, etc. also have new uses. Since manganese has a strong catalytic oxidation and catalytic reduction, ion exchange and adsorption capacity, after through suitable chemical treatment forming, it is a excellent overall performance water filter, compared with the commonly used activated carbon, zeolite, water filter, it with stronger bleaching and remove heavy metals ability. Therefore, from waste zinc-manganese batteries will be recycled in various forms of manganese, has important environmental sense and good economic prospects.

Currently, many countries have set up a complete battery recycling processing system, the processing methods mainly have pyrometallurgical recovery method and hydrometallurgical recovery method. Some Chinese researchers on this basis, through improving traditional methods, and combined with the actual production, raise some with development prospects waste batteries utilization new technologies and processes. From the environmental point of view, the current fire method likely to cause serious air pollution, wet method use a lot of acid, cost too high, the treated effluent and waste likely to pollute the environment. For the disadvantage of existing methods, Chinese researchers have proposed using membrane electrolysis slurry method, restore the dry cathode material in the cathode chamber, prepared manganese sulfate solution, in the anode chamber turn into the manganese oxide, manganese dioxide or manganese oxide. Here introduce the experimental methods of battery cathode material reducing and leaching in the cathode chamber.

Vertical cut some used batteries, peel off the outer skin of zinc, weigh a certain amount of grinding good positive part, by a certain liquid and solid ratio, added to the sulfuric acid solution, uniform mixing electrolyte in the cathode chamber, constant current electrolysis in all factors conditions, the electrolysis time is 90min, every 15min sampling 3mL to filtered, sampling 1mL, diluted with deionized water to a 100mL flask, measuring the absorbance, calculating the concentration of manganese ions, and recovered.

Source:http://www.mhcmp.com