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In order to make the natural quartz up to the standard of high purity quartz sands, quartz ores are processed to obtain high purity quartz sands by the purifying technologies which include grinding, high-intensity magnetic concentration, flotation and acid leaching, washed by deionized water. The phase, morphology and composition of the prepared quzrtz sands were determined by X-ray diffraction, scanning electron microscope and inductively coupled plasma spectrometers.The results show that impurity minerals adsorb onto the quartz mineral surfaces. Magnetic minerals were removed by magnetic concentration experiment, while other impurities were removed by flotation and acid leaching experiments and they show excellent cleaning effect. Finally a high purity quartz product which contains higher than 99.95% SiO2, less than 0.003% Fe2O3, and less than 0.01% Al2O3 was obtained.

The extraction and stripping characteristics of Versatic 10 and its mixtures with Cyanex 301 were investigated for the recovery of cobalt and nickel from sulfate solutions containing magnesium and calcium. The optimum extraction factors of Versatic 10 were initial pH of 2.5, O/A ratio of 1/3, and saponification rate of 60%. The loaded Versatic 10 was stripped by using 2 mol/L H2SO4at O/A ratio of 1/1. The optimum volume ratio of Versatic 10 to Cyanex301 was 7/3 in the mixtures, which could effectively reduce the equilibrium pH to 3.50. And the loaded mixtures were stripped by using 2 mol/L H2SO4at O/A ratio of 1/2. The reaction principle of Versatic10 and metal ions is an ion exchange reaction. However, in the extraction reaction of and metal ions, besides the ion exchange reaction, the strong coordination effect between Cyanex 301 and metal ions also exists, which is much weakened in the extraction reaction of the mixtures and metal ions.

The effect of solvent extractants, such as M5774, Cyanex 272, P204, P507 and N235, on the activity and community structure of acidophilic microorganisms were tested. Cobalt extractant Cyanex 272 did not show much inhibition effect on the growth of acidophiles, while iron extractant N235 had great inhibition effect. When the culture solution contacted with iron extractant P204, nickel extractant P507 and copper extractant M5774, the inhibition effect increased gradually. 16S rRNA gene clone library were used to analyze the initial and extractant contacted final microbial community structure. The initial inoculation microbial populations were mainly composed by Leptospirillum ferriphilum and Acidithiobacillus ferrooxidans. After cultivated in solution containing extractant M5774, Cyanex 272, P204 and P507, the number of the two species decreased, while heterophilic Acidiphilium cryptum became the dominant population. When cultured by M5774 and Cyanex 272, the proportion of Acidithiobacillus ferrooxidans was higher than Leptospirillum ferriphilum, while when cultivated by P204 and P507, the number of Leptospirillum ferriphilum was higher.

In this paper, we jointly use the Pitzer model and the Meissner model to study thermodynamic laws of bioleaching solution in a lean nickel-cobalt ore in the Jilin Baishan, by using the Pitzer model to calculate activity coefficients of single electrolyte aqueous solutions and the Meissner model to calculate activity coefficients of components in the bioleaching solution. Also we studied the rules of activity coefficient of NiSO4 and CoSO4 in the solution. Results show that when separating and purifying foreign ions from bioleaching solution of the lean nickel-cobalt ore, the descending sequence of their ion concentration’s effect over the solution is Mg2+, Fe3+, Fe2+, Ni2+, Co2+ and Ca2+.

The tailing in a large lead-zinc-iron-sulfur multi-metallic mine has rich reservation in variety of metallic minerals. It has been difficult to recover because of all kinds of reasons. The challenges faced by lead-zinc ore beneficiation are, low grade and recovery of lead and zinc concentrate for fine disseminated grain size, high oxidation rate and close intergrowth. This paper presents a Pulp Potential Control Flotation by stages technique to improve the flotation performance of the lead-zinc ores. In the electrochemical potential controlling flotation processing, using DDTC as collector, the separation potential range of galena and sphalerite with pyrrhotite can be achieved. Flotation circuit of lead-zinc-silver tailing ore was achieved.

The influence of different concentrations of calcium nitrate on the growth and activity of acidophilic microorganisms were studied and the microbial community structures were compared by 16S rRNA gene clone library analysis. The addition of Ca (NO3)2 has a certain effect on the solution potential, and that the time needed to reach the steady potential were prolonged with the increase of Ca (NO3)2 concentration but not obvious when it was above 1.64 g.L-1. It also can be observed that the cell numbers decreased with the increase of Ca (NO3)2 concentration which can alter the cell osmolarity, and that the time entering the stationary phase of cell concentration was delayed with the addtion of Ca (NO3)2. With the addition of 0.41g.L-1 Ca (NO3)2, the percentage of Leptospirillum ferriphilum and Acidiphilium cryptum didn’t have great changes, while the uncultured Sulfobacillus sp., Acidithiobacillus ferrooxidans and Alicyclobacillus tolerans were also detected. With the addition of 2.05 g.L-1 Ca (NO3)2 or more, the Acidithiobacillus ferrooxidans become the dominant bacterium (which accounted for more than 90%).

As an effective method for increase extraction efficiency and selectivity,synergistic extraction has been studied for many years because the theoretical and applicative importance. Using synergistic effect of two extractants, distribution ratios of their mixture can be obviously enhanced than those of their individual contributions. Separation of nickel and cobalt for bioleaching solution were studied using a synergistic extraction system with P507 andCyanex272. The test results indicate that the system has better extraction effect. Contrasts the separation effect on nickel and cobalt using three extraction systems of P507, Cyanex272, P507-Cyanex272. Identified during the initial pH value of 1.5-2.2, balance pH value under the condition of 4.0-5.0,synergistic extraction system of P507-Cyanex272 have a good separation effect of nickel and cobalt. The extraction kinetics was investigated using a constant interfacial cell with laminar flow. The effects of temperature, extractant and cobalt concentration were studied. Co extraction rate was compared in the different extraction systems of individual P507 and synergistic P507-Cyanex272 .The results indicated that the extraction apparent action energy in synergistic system was lower than that of signal P507.The separation factor of nickel and cobalt was increased in synergistic system.

Effect of microorganisms and nickel sulfide ore before and after bioleaching on the emulsification was investigated. The emulsion stability was evaluated by the disengagement time or the production rate of crud. The results indicate that no crud formed and the disengagement time of system was prolonged with increasing bacteria density. And a large number of bacteria dispersed at the water-oil interface and aqueous phase and rarely existed in organic phase. The influence of bacteria on the emulsion stability was attributed to the structural characteristics and the mass transfer viscosity. And the emulsion with nickel sulfide ore after bioleaching was more stable, characterized as higher production rate of crud and lower light transmittance of aqueous phase, because bacteria alter the surface properties of minerals and increase particles’ hydrophilicity.

Based on the bioleaching mechanism and electrochemical studies of metal sulfides, the dissolution rate of secondary copper sulfides and pyrite are controlled by redox potentials. Experiment on the bioleaching of the secondary copper sulfides under constant potential by sparging with nitrogen gas demonstrated, by analyzing Cu and Fe content of the bioleaching solution and residues, the pyrite and secondary cooper sulfides dissolution rates have large difference in various redox potential. The pyrite and secondary cooper sulfides have good selection when the redox potential controlled between 700mV and 760mV, we can realize the secondary copper sulfides bioleaching process be controlled, then supply theoretical guide for the iron-acid balance during copper bioleaching process.

The release of amino acids in the locus coeruleus (LC) of conscious, freely moving rats was studied in time periods of 3 min by use of push-pull superfusion under basal conditions and during application of various experimental stimuli known to influence the activity of the LC-noradrenergic system. Tail pinch for 3 min led immediately to a pronounced tetrodotoxin-sensitive increase in the release rates of the excitatory amino acids (EAA) glutamate (Glu) and aspartate (Asp) and to moderate increases in GABA and taurine (Tau) outflow. Immobilization stress for 9 min elevated the release of the EAA Glu and Asp, as well as that of the inhibitory amino acid GABA to a similar extent. A fall of blood pressure (BP) by nitroprusside or haemorrhage slightly enhanced the release rates of Glu and Asp. Noradrenaline-induced rise in BP, as well as hypervolaemia increased the release rate of GABA, but did not influence the release rates of Glu, Asp, Tau and arginine (Arg). The results provide direct evidence that the amino acid release pattern in the LC of conscious rats differs in response to various stimuli, according to the modality of the stimulus. A functional significance of excitatory and inhibitory amino acids in the regulation of LC activity during stress and haemodynamic changes is suggested.

During Zijinshan copper heap bioleaching, pyrite was leached in plenty resulting in high ferric concentration in solution. This affected bioleaching and extraction processing greatly. The paper studied the factors influencing in the course of leaching of pyrite and a mixture of chalcocite and pyrite respectively. It focuses on the effect of the redox potential for copper bioleaching so as to find key factors affecting the dissolution difference between chalcocite and pyrite. The experiment results showed that redox potential is an important influencing factor in bioleaching. Copper and pyrite extents of the leaching process were 95% and 11% respectively and there is great dissolution difference between them at redox potential 700 mV (SHE). It is indicated that copper can be selectively bioleached by controlling redox potential of bioleaching. The conclusion will provide theoretic foundation on balance of acid and iron during bioleaching for copper of higher S/Cu ratio. A simple sulfide, pyrite and chalcocite, were selected as test minerals. The samples were obtained from rich mineral in Zijin Mine. The concentrated samples were milled to obtain the size fraction of 320 mesh percent of 90. Bacterium culture: 9K culture medium contained the following composition in kg/m3 distilled water: (NH4)2SO4, 3.0; K2HPO4·3H2O, 0.5; KCl, 0.1; MgSO4·7H2O, 0.5; Ca(NO3)2·2H2O, 0.01. The initial ferrous concentration was 9.0g/L, the initial pH was adjusted to 1.6, and the temperature set at 30°C. The rotation speed of shaking bed was 150r/min. A three-day-old inoculum previously grown in medium was used in bioleaching process. A 5% inoculum was added to give an initial bacteria concentration in the medium was (3-6)×107 cells/m3. The experiments investigated factors influencing bioleaching including ferrous concentration and redox potential during bioleaching. The extent Cu leached was over 90%. Cu leached velocity increased as redox potential turned higher. Cu leached velocity rapid increased at redox potential 700mV. During chalcocite and pyrite bioleaching, redox potential is important factor to influence of bioleaching rate and the results showed that pyrite and chalcocite bioleaching rate was correlated with redox potential. It is indicated that copper can be selectively bioleached during copper bioleaching by controlling redox potential of bioleaching. It can be concluded that: (1) Pyrite and chalcocite bioleaching rate was correlated with redox potential. Redox potential was shown to be the key factor affecting the dissolution difference between chalcocite and pyrite. (2) Chalcocite and pyrite leaching efficiency were 95% and 11% respectively and there is great dissolution difference between them at redox potential 700 mV (SHE). (3) It is indicated that copper can be selectively bioleached during copper bioleaching by controlling redox potential of bioleaching.