Study On Recycling Sulfur From Oxygen Pressure And Acid Leaching Zinc Slag

Some oxygen pressure acid leaching of zinc slag contains about75%of element sulfur,which also contains a certain amount of precious metals, in order to improve the utilizationrate of resources, protect environment, enrichment precious metals, recycling of elementsulfur is necessary.Paper adopted hot filtering method and solvent method of kerosene, ammonium sulfide,xylene to recycle element sulfur from high pressure acid leaching zinc slag, and thedesulfurization results were studied and compared. Study showed that solvent method hadhigher desulfurization rate and less time than hot filtering method. And xylene has higherdesulfurization rate, less time than kerosene, ammonium sulfide, it did not dissolve preciousmetals. So choose xylene as desulfurizer, and do a further research on optimal conditions,minimum economic costs, cycle times, dynamics, microwave assist xylene desulfurizationand solubility for the sulfur in xylene.The results showed that the optimal conditions of liquid-solid ratio of8:1, stirring for10min at95°C, the xylene desulfurization rate is97.47%, at the same time, unit time unittemperature unit volume desulfurization rate represent economic cost, the optimal conditionsis liquid-solid ratio of7:1, stirring for5min at95°C, it is1.849g.(ml.°C.min)-1, theproduction cost is lower. Usually the actual production under the condition of high leachingrate is not the lowest economic cost, the actual production depends on the actual situation.Xylene can be recycled many times, the ninth desulfurization rate is about96%. Xylenedesulfurization follow contraction nuclear dynamics model, time has a linear relation with123R1R23, apparent activation energy is28.89KJ.mol-1, belongs to the internaldiffusion control. Using microwave assist xylene desulfurization, the optimal conditions isliquid-solid ratio6:1, high power for10min, the desulfurization rate can reach98.12%,compare with xylene desulfurization, the liquid-solid ratio from8:1fall to6:1, improve thedesulphurization rate, change control link and reduce the economic cost. The date ofsolubility for the sulfur in xylene is not complete, it has theoretical guidance meaning forextracting element sulfur to measure the solubility of sulfur in xylene at a series oftemperature. the experiment using gravimetric method and the correlation of the experimentdatas uses many models. the results showed that empirical model fitting effect is better, thefitting equations is:x=1.04241×10-6T3-9.81309×10-4T2+0.31033T-32.85829 R2is0.9984, relative error almost less than2%.