| A innovative technology with independent property right of knowledge on preparation of ultra-fine active zinc oxide by comprehensive utilization of zinc dross has been investigated and developed in this paper. The whole flow of preparation of ultra-fine active zinc oxide by comprehensive utilization of zinc dross and pilot test has been completed systemically. Testing showed that preparation of ultra-fine active zinc oxide by comprehensive utilization of zinc dross was feasible. Some main results of testing research were as fellows:i.In the course of testing of leaching zinc dross, leaching zinc dross by sulfuric acid was researched and the effects on the leaching rate of the zinc dross were analyzed by author, the optimum conditions of leaching testing of zinc dross were determined as fellows: liquid-solid ratio 6:1, stirring ratio 250r/min, granularity 120 mesh, the soaking time 5h, the concentration of sulfuric acid of 30%, and under these conditions, the rate of leaching zinc is above 92.0%.ii. In the course of testing of purification, on the basis of comprehending and comparing all present methods of the manganese-removal and iron-removal, the oxidizing method of manganese-removal in zinc sulfate solution using ammonium persulfate was put forward and the oxidizing method of iron-removal in zinc sulfate solution using the goethite process and oxidation- hydrolysis process was adopted. The effects on the manganese-removal rate and iron-removal rate of zinc sulfate solution is analyzed and discussed in detail. The optimum conditions of manganese-removal were determined as fellows: temperature 90C,pH=5.4, heated-time 2h, the quantity of ammonium persulfate above the quantity of theory counting 1.2 times and under the these conditions,the manganese-removal rate was above 99.86%. The optimum conditions of iron-removal were determined as fellows: oxygenation and reaction time of 1.5h, temperature 90~92C,pH 5.2-5.4, the quantity of hydrogen superoxide above the quantity of theory counting 1.8 times, additive time of 3h, and under the these conditions, the iron-removal rate was better. Moreover, the optimum purification conditions of lead-removal, cadmium-removal and cobalt-removal and so on by addingzinc power were determined as fellows: temperature 70~80C,pH 5.2-5.4, reactiontime of l~1.5h, the quantity of zinc power above the quantity of theory counting 2.8 times.iii. Preparation of precursor of basic zinc carbonate of active zinc oxide by means of ultrasonic radiation was introduced firstly, and a mechanism on preparation of precursor of basic zinc carbonate of active zinc oxide by means of ultrasonic radiation has been investigated emphatically as well as the effects on quality of precursor of basic zinc carbonate have been analyzed and discussed in detail. The optimum conditions of preparation were as fellows: the concentration of zinc sulfate solution of 1.8-2.Omol/L, the concentration of ammonium bicarbonate solution of 1.4~1.6mol/L, the time of ultrasonic radiation of 25~30min.iv. Preparation of active zinc oxide by means of microwave radiation to calcine precursor of basic zinc carbonate firstly, and a mechanism on preparation of ultra-fine active zinc oxide by means of microwave radiation has been investigated emphatically as well as the effects on quality of ultra-fine active zinc oxide have been analyzed and discussed in detail, the time of microwave radiation was 7~16 min; comparing microwave radiation calcining with conventional calcining, the calcining time of microwave radiation was one thirty to one twenty, the calcining time shortened hugely, energy consumption saved hugely, the quality of product improved.v. Experimentation and pilot test of the whole flow of preparation of ultra-fine active zinc oxide by comprehensive utilization of zinc dross have been completed. The microstructure, granularity and morphology of the product were characterized by EPMA-1600.EPMA-1600 studies showed that the ultra-fine active zinc oxide was spherical structure with distribution and granu...
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