| The waste carbon aluminum slag is the residual slag of carbon aluminum material used as fireworks and crackers.The aluminum content is very high and the composition is complicated.In this paper,for the purpose of comprehensively utilizing the waste carbon aluminum slag and protecting the environment,in order to extract the aluminum in the waste carbon aluminum slag,using sulfuric acid as the solvent,NH4F was used as leaching aid agent to soak up the waste carbon aluminum slag,and the alumina in the waste carbon aluminum slag was converted to aluminum sulfate solution.Under normal pressure,the effect of sulfuric acid concentration,sulfuric acid dosage,leaching temperature and leaching time on the dissolution rate of alumina in the process of leaching of waste carbon aluminum slag was investigated by single factor experiment,explore the role of the leaching aid agent in the leaching process,the optimal technology conditions are:the concentration of sulfuric acid is 40%,the leaching temperature is90?,the leaching time is 90min,the solid-liquid ratio of waste carbon aluminum slag and sulfuric acid is 1:5,the quality ratio of NH4F and waste carbon aluminum slag is 0.08,the leaching rate of aluminum has reached more than 83%.The aluminum in the waste caborn aluminum slag was assisted extraction by microwave thermal activation.The optimum conditions are:microwave power is 450W,microwave activation time is 10min,the concentration of sulfuric acid is 40%,the leaching temperature is 90?,the leaching time is 90min,the solid-liquid ratio of waste carbon aluminum slag and sulfuric acid is 1:5,the quality ratio of NH4F and waste carbon aluminum slag is 0.08,the leaching rate of aluminum has reached more than 90%.Using alkali soluble iron method,a certain amount of H2O2 solution was added into the prepared aluminum sulfate solution to convert Fe2+to Fe3+,evaporated to a definite volume,then added an excess amount of 4mol/L NaOH solution at a certain temperature after a certain time of reaction solution pH is greater than 12,the Al3+is converted into partial aluminate,which enters the solution,and the precipitates such as Fe,Mg and other metal ions in the solution was generated,eliminated by filtering,the removal rate of iron was above 98%;adjusting pH,introducing CO2 gas to producting Al?OH?3 precipitation,filtration,washing Al?OH?3 precipitation with deionized water.The Al?OH?3 precipitation is calcined at different temperatures to product alumina.Research shows that:The Al?OH?3 precipitation is calcined 2h under the temperature of800?and the the?-Al2O3 and?-Al2O3 will be obtained;calcined 2h under the temperature of 1200?and the?-Al2O3 will be obtained.Alumina powder is obtained by grinding.XRD,SEM and FT-TR methods showed that the product is?-Al2O3. |
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