| On the basis of summarization of the research results on the treatments of arsenic refractory gold ores and the leaching process of mechanical activation enhancing leaching, how to further study on the mechanism of mechanical activation enhancing leaching has been put forward by means of using modern analysis and test apparatus. Following several questions have been researched using Guangxi Guiguang arsenic-bearing gold concentrate and gold-carrying minerals-pyrite and arsenopyrite as test materials in the normal stirring leaching equipment and mechanic activation equipment ( stirring mill, rolling mill and vibrating grinder) respectively with the combination of modern analysis and test means, such as scanning electron microscope(SEM), X-ray diffraction (XRD) accurate analysis and so on:(D Researches on the technological conditions of one step leaching gold by sodium hypochlorite for finding the main influencing factors of gold leaching rate;(2) Examining thermodynamics and dynamics of enhancing liquid solid leaching process using mechanical activation ways;(3) Looking for the effects of different mechanical activation ways on the gold leaching from refractory gold ore and the enhancing effects;(4) Exploring the analysis method to test the characteristics of shape and appearance of semiconductor minerals by SEM without coating on the surface;(5) Studying the mechanism of mechanical activation enhancing leaching by the characteristics of shape and appearance;(6) Further verifying the process and the mechanism of mechanical activation enhancing leaching by the use of various test means including XRD, differential thermal analysis(DTA), specific surface analysis and so on.The following main conclusions have .been obtained on the basis of the experimental results and theoretical analysis through above researches:?In the system of NaOH ?NaCIO, Au, As and S can be leached simultaneously by one step, in addition, the leaching thermodynamics trends of As and S are bigger, but Au is mainly existed in the presence of H2AuO3" and HAuO32", the corresponding thermodynamics trend is smaller. The leaching process ismix-controlled model by chemical control and inner diffusion control.(D Mechanical activation can enhance the mineral leaching in the leaching gold system of NaOH桸aClO. The leaching rate of Au is up to peak by using 04mm corundum ball with 95% A12O3 as activation medium for 50~60min in the rolling mill when the initial concentration of sodium hypochlorite and sodium hydroxide are 2.3 mol/L and l.Omol/L respectively and liquid-solid ratio is 10, the leaching rate of Au is increased to 85% from 60% without activation, about 40% Au leaching rate is promoted. The leaching rate of As and S also are enhanced by 11% and 27% respectively.(3) The activation of accrete minerals, the heating decomposition loss of sodium hypochlorite and the presence of organic carbon in gold concentrate are the main reasons for the change of Au leaching rate with the change of reaction time hi wave peak state in the gold leaching system of NaOH-NaClO, it can clear this influence by increasing initial concentration of sodium hypochlorite.(4) The characteristics of shape and appearance of minerals after mechanical activation can be observed clearly and directly with improved SEM analysis way. Through XRD accurate analysis with the internal standard method of high-purified silicon, the calculation of unit cell constant, unit cell volume, interplanar distance and disordered degree, and the analysis of DTA, density and specific surface, the presence of amorphous substance on the mineral crystal after mechanic activation is verified unanimously. Floccule watched on the mineral surface in the analysis of SEM is live embodiment of amorphous substance.(5) In the leaching process of mechanical activation, minerals obtain energy and this energy makes crystal lattice distortion and produce defect, this embodiment is to produce high energy and high activity amorphous substance on the mineral crystal, A7G?of reactants is increased...
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