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Germanium scattered metal, low levels in the earth's crust, the formation of an independent and deposits of economic value, most exist in the form of a compound silicate and sulfide ore. Due to the excellent physical and chemical properties of germanium, a very wide range of applications, is becoming increasingly important in the national economy and military in recent years, with the rapid development of the information industry and new energy, global demand along with the rapid growth of germanium, germanium recovery increasingly more concern and attention by the researchers. Yunnan enterprises atmospheric sulfuric acid leaching leaching slag containing germanium germanium, germanium leaching rate of only about 55% of the resource utilization is low, in order to improve the germanium comprehensive utilization of resources, the papers concentrated acid curing process slag leaching of an enterprise germanium to improve the leaching rate of germanium and comprehensive recovery of germanium purpose. Firstly, thermodynamic leaching of germanium, the kinetic theory, and maturation of concentrated acid the Si02 change process analysis, ripening concentrated acid leaching germanium provide theoretical support; then concentrated acid curing - flooding germanium technology experimental study by factor experiments to examine the influence of different factors on the process of concentrated acid, screening out the important factors, optimization experiments using response surface center rotary design method, optimization experiments, the establishment of an appropriate leaching model, and finally examined flooding the impact of various factors on the leaching rate of germanium, and leaching containing germanium solution subsequent processing and analysis. The main research contents are as follows: First E-pH diagram draw germanium water system, the E-pH diagram analysis, to draw raw germanium oxide can be dissolved in acid, and the acidity of the higher solubility of the better, increase the concentration of sulfuric acid can speed up the speed of the reaction, and the conventional leaching kinetics experiments, kinetic experiments such germanium-containing slag sulfuric acid leaching are within generate solid product layer diffusion control, germanium leaching kinetics equation can be expressed as: Kc = K0 · r-1 · [H2SO4] 1.654 · exp [-10640/RT]. Finally, through the the Si02 contrast changes in dilute acid and concentrated acid process, come to form a stable form of SiO2 in the concentrated acid conditions, can improve the filtration conditions and to reduce silica gel adsorption on germanium, improve the leaching rate of germanium. The concentrated acid maturation factor experiments show that the concentrated acid curing optimum conditions: the weight of the material to 40g conditions, the grinding time 4min, the amount of water and the amount of acid was 20 g, aging temperature of 80 ° C, the curing time 3h, germanium leaching rate was 71.6%. Obtained by experiment the particle size of the ripening process of the concentrated acid and sulfuric acid in an amount greater impact on the leaching rate of germanium, curing temperature and curing time of less influence, mainly because in the mixed acid process, the temperature instantly reach high, concentrated sulfuric acid and the reaction of the material at this stage. Optimize experimental design, response surface methodology central composite rotatable through experiments to establish the maturation of concentrated acid leaching of germanium regression mathematical model: Y =. 72.63 21.65χ1 0.53χ2 1.06χ3-0.100χ1χ2-0.24χ1χ3 0.12χ2χ2-11.27χ12-1.25χ22 1.47χ32. The correlation coefficient R of 0.9067, accuracy of 33.979 is greater than 4, R2adj = 0.9765, also found that the amount of sulfuric acid leaching rate of germanium significant. Design-Expert software best optimization parameters: the material under 40g conditions of the amount of sulfuric acid 30g, ripening time 44.52min, 43.56 ° C germanium leaching rate higher, the leaching rate of 79.14%. Under the conditions of this optimization, the process conditions has a short curing time, curing temperature is low, a high germanium leaching characteristics. Flooding experiments, the flooding process parameters: the leaching time was 1h, the acid concentration of 0 g / L, the leaching temperature of 90 ° C, the liquid to solid ratio of 4, germanium leaching rate of 78.88%, concentrated acid curing consolidated under the conditions germanium leaching rate of 78.88%. By the acidity of the solution after the flooding, the germanium ion concentration analysis and research on the industrial production of germanium sedimentation process, draw the concentrated acid curing - flooding after the solution for precipitation process. In short, on the basis of theoretical studies of the thermodynamics and kinetics of germanium slag leaching process, response curved central composite rotatable design method optimization experiments, such residue in germanium leaching rate, proved a concentrated acid curing The technology has obvious advantages in dealing with this type of slag, this study to expand the range of applications in the field of scattered metal concentrated acid curing process.
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