Papers by Author: Hong Zhou Ma

Abstract: The aim of this paper is to contrast the effect of the microwave heating and traditional heating leaching vanadium from stone coal with sulfuric acid solution, contrast the leaching rate of vanadium, kinetics of leaching vanadium and the phase change s of slag. The experiment results show that the leaching rate and leaching velocity of vanadium with microwave heating was higher greatly than traditional heating, the kinetics of leaching vanadium with two heating methods was similar and accords with unreacted core contraction model with have solid product layer model, the illite in the stone coal was decomposed with microwave heating, but the traditional heating could not decomposed.

Abstract: Aiming at the difficulties of aurum leaching from arsenic gold ore, the behavior of arsenic and aurum leaching by the roasting pretreatment of arsenic gold ore is discussed. The result indicates as the following: the rate of aurum extraction is only 14.16% to this kind of refractory gold ore by choosing normal method of aurum extraction. However, the rate of fixing arsenic is up to 95.77% and the aurum extraction rate is 78.45% through the pretreatment of fixing arsenic roasting under optimum roasting conditions like adding amount of CaCO₃ by 3%, roasting temperature 650°C and roasting time 4 hours. The result is satisfactory.

Abstract: Techniques are applied for the sorption of rhenium from the leaching solution of the fume of calcinating molybdenite concentrate by 201×7 strong base anion exchange resin. By analyzing the main ion from the leaching solution be pretreatmented, the 201×7 strong base anion exchange resin be used in experiment. The influencing factors on the sorption were investigated, with medium pH, the existing form of the ion in the solution and the pH are greatly related to the ion exchange capacity , the result show that the resin not only have higher adsorption rate of ReO₄^-, but also have higher separation factor of ReO₄^- and MoO₄^2- when the leaching solution was pretreated pH at 9.0. The separation factor of ReO₄^- and MoO₄^2- reached to 980.5. 5%NH₄OH+9%NH₄Cl solution is a effective desorption reagent for molybdenum, the desorption rate is 96% and nitric acid solution is a effective desorption reagent for rhenium on the loaded resin after desorpted the MoO₄^2-,the desorption rate of ReO₄^- is 98%.

Abstract: Based on the high temperature compression simulation experiments, the mechanical behavior of Ti-6AI-2Zr-1Mo-1V alloy were studied over the range of temperature from 850°C to 1100°C , strain rate from 0.01 to 10s^-1. The results show that the flow stress reduces with temperature increasing at the constant strain rate and increases rapidly with strain rate increasing at the constant temperature. The stress index n and deformation activation energy Q is respectively 7.0874 and 610.463 kJ/mol at 850-950°C . While at 950-1100°C , n is 4.7324 and Q is 238.030 kJ/mol. From the obtained processing map, it is found that two unstable regions present at the lower temperature or higher strain rate and two optimum regions in hot deformation process. The unstable zones are 850-950°C , 0.001-0.008s^-1 of strain rate, and 940-1030°C , 2-10s^-1 of strain rate respectively. In the optimum zone with the temperature range of 1060-1100°C , strain rate of 0.05-0.65s^-1, and the peak efficiency of power dissipation of about 0.42; while in the other zone with the deformation temperature 890-940°C , strain rate of 0.06-0.18s^-1, and the peak efficiency of power dissipation of about 0.33.

Abstract: Technological process of microwave-assisted leaching of vanadium with sulfate solution has been defined on the base of phase and chemical constituents of stone coal. The influence factors such as content of sulfuric acid, microwave power, and leaching time were studied on leaching rate of vanadium from the stone coal. One element experiments and orthogonal design experiments are carried out to achieve optimized parameters. The experimental results showed that the leaching rate of vanadium was improved by the change of influence factors at some range. The single leaching rate of vanadium reached 80.9% under the optimal conditions of sulfuric acid content of 12%, microwave power 539w,leaching time of 2h.