| Manganese is one of the most important alloy elements in smelting alloy steel, but also manganese salt has intensive use in agriculture, light industry and chemicals. Therefore, the leaching technology of pyrolusite is always the important research content at home and abroad. The technology and kinetics of pyrolusite was studied in acid solution by using the cane molasses as reducing agent, which was the regeneration resource.The single factor experiment and orthogonal design were planned to study the effect of the process factors: temperature, time, sulphric acid concentration and cane molasses concentration and so on were taken in consideration in the experimental test. The optimum leaching condition were obtained using 2.35mol·L-1 H2SO4 and 75 g·L-1 cane molasses to pyrolusite for 120 min at 90℃and 200 r·min-1. These conditions resulted in leaching yields of 95% for Mn, with relatively low recoveries of 43.4% for Fe and 32.7% for Al.Temperature and sulphric concentration had the most important influence on the extraction of Mn, Fe and Al. Through the fractional experiment and single experiment, it was found the depression in Fe extractions in the presence of cane molasses.In addition, we had the study on the kinetics of the pyrolusite leaching. Leaching processing follows unteacted shrinking core model and the apparent activation energy was determined to be 45.62kJ·mol-1, the grades of sulphric acid and cane molasses were 0.518 and 0.280 respectively. It was concluded that the leaching process was controlled by chemical reaction control. The equation accorded with the kinetics characters was:1-(1-x)1/3= 2033.7/r0Ca0.518Cm0.280 exp((-45.62)/RT)t...
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