The extraction and separation of ferrum and copper from waste ternary cathode material by Cyanex 302 (the main component is di (2,4,4-trimethylamyl) monothiophosphoric acid) was studied. The effects of H⁺ concentration, extractor concentration and temperature on the extraction and separation performance of Cyanex 302 were investigated. And the technological conditions for the stripping of ferrum and copper in supported organic phase were determined. The process flow of extracting ferrum and copper from waste ternary cathode material leaching solution is designed. The results show that the optimal extraction conditions are 0.1 mol/L Cyanex 302 concentration, 0.1 mol/L H⁺ concentration, room temperature.Under these conditions, the extraction rates of ferrum and copper are over 99.9%, while the extraction rates of Ni(Ⅱ), Co(Ⅱ), Mn(Ⅱ), and Li(Ⅱ) are all below 0.003%. The optimal stripping agent for ferrum is 1 mol/L H₂SO₄, and that for copper is 1.5 mol/L HNO₃.The process can effectively separate copper and ferrum from the leaching solution.

The removal of Mo(Ⅵ) from wastewater was studied by using jarosite after iron deposition in zinc leaching solution as adsorption material. The effects of the initial pH of simulated wastewater, the initial mass concentration of Mo(Ⅵ), the additon amount of jarosite and the adsorption time on the adsorption of Mo(Ⅵ) by jarosite were investigated, and the kinetic mechanism of the adsorption process was discussed. The results show that under the conditions of initial mass concentration of Mo(Ⅵ) of 40 mg/L, pH=3.0, additon amount of jarosite of 1.0 g/L and adsorption time of 240 min, the adsorption capacity of Mo(Ⅵ) can reach 13.21 mg/g. The adsorption process of Mo(Ⅵ) in wastewater by jarosite is more suitable to be described by quasi-second-order kinetic model, which belongs to chemical adsorption. The adsorption process of molybdenum by jarosite follows the Langmuir isothermal adsorption model and has higher fitting accuracy. The adsorption process belongs to monolayer molecular adsorption. This method has the advantages of simple process and low cost, and is expected to realize high-value recycling of waste residue.

The preparation of activated carbon from coffee grounds by activated roasting coffee grounds with NaOH and the adsorption and removal of Cu(Ⅱ) from wastewater containing copper were studied. The activated carbon of coffee grounds was characterized by SEM and EDS. The effects of initial pH of wastewater, initial mass concentration of Cu(Ⅱ), adsorption time and amounts of adsorbent on the adsorption of Cu(Ⅱ) were investigated. The results show that for the 50 mL simulated copper-containning wastewater with mass concentration of 50 mg/L and pH=6, under the optimal conditions of activated carbon from coffee grounds amounts of 10 mg, temperature of 25 ℃ and stirring speed of 150 r/min and adsorption time of 9 h, the Cu(Ⅱ) adsorption removal rate can reach 94.12%. Langmuir isothermal adsorption model and quasi-second-order kinetic model can describe the adsorption process well. The adsorption performance of Cu(Ⅱ) in wastewater is good.

Gallium, indium, cadmium, selenium, tellurium, germanium, thallium and other rare disperse elements are often present in copper deposits, and accurate analysis of these elements is beneficial to comprehensive utilization of minerals. The determination of Ga, Ge, In, Tl, Se, Te and Cd in copper ore by microwave digestion and inductively coupled plasma mass spectrometry was established. The symmetric sample size, acid system, ethanol concentration, microwave digestion work conditions and mass spectrum interference were optimized. The results show that under optimized conditions, the linear correlation coefficient of the calibration curve is greater than 0.999 5, and the detection limit is 0.002~0.19 μg/g. The relative standard deviations (RSD, n=6) are 2.63%~13.84%, and the standard recoveries are 90.4%~110.6%. The method is accurate and reliable, and the results are consistent with the standard method.

In order to promote the recovery and utilization of valuable resources in steel slag, the leaching behavior of each element in converter steel slag in mixed acid (citric acid+nitric acid) system was studied. The effects of mixed acid concentration, reaction time, reaction temperature, liquid volume to solid mass ratio, and slag particle size on the leaching rate of each valuable element were examined. The results show that acid concentration, reaction time, liquid volume to solid mass ratio, and slag particle size have significant impact on the leaching rate of calcium, magnesium, iron, manganese and phosphorus. The reaction temperature has little effect on the leaching rate of each element. Under the conditions of steel slag particle size of 65 μm, leaching temperature of 298 K, leaching time of 30 min, liquid volume to solid mass ratio of 300∶1 and stirring speed of 800 r/min, the leaching rate of phosphorus is 88.15% with 0.01 mol/L nitric acid and 20.8 mmol/L citric acid. And effective leaching of phosphorus is obtained.

The separation and enrichment of precious metal gold in chloride system with synergistic extraction system composed of DIBK (HA) and TBP (B) was stuied. The effects of extraction system and composition, extraction time, extraction temperature, aqueous chloride ion concentration,and extraction ratio (V_O/V_A) on the separation performance of gold extraction was investigated, and the extraction mechanism was preliminarily explored by slope method. The results indicate that under the conditions of synergistic extraction system of TBP-DIBK, total extractant concentration of 1.5 mol/L, n(TBP)∶n(DIBK)=1∶4, extraction time of 20 min,extraction temperature of 20 ℃, V_O/V_A= 2/1, aqueous chloride ion concentration of 6 mol/L, the extraction rate of gold can reach 98.82%.The maximum gold/copper extraction separation coefficient is 1 189.05. Gradient method suggests that the composition of the extract may be [AuCl₆·3A·B]. The extraction chemical reaction formula can be rewritten as: Au³⁺+6Cl^-+3HA+B→[AuCl₆·3A·B]+3H⁺.

The change of iron grade in the leaching residue and the leaching kinetics under normal pressure and pressure were examined. The pressure leaching of nickel and cobalt from a high iron and low grade laterite nickel ore in Indonesia with sulfuric acid was studied. The results show that under the conditions of acid/ore ratio of 260 kg/t, leaching temperature of 250 ℃ (corresponding to water vapor pressure of 4.0 MPa), liquid volume/solid mass ratio of 3/1, stirring speed of 300 r/min, particle size of 100 mesh and reaction time of 1 h, the leaching rates of nickel, cobalt and iron are 98.1%, 98.3% and 4.7%, respectively, and the iron grade can reach 51.3%. The leaching processes of nickel and cobalt under pressure and atmospheric pressure are in line with the shrinkage kernel model of interfacial chemical reaction control, and the activation energies of the reactions are 116 kJ/mol and 91 kJ/mol under pressure, respectively, and the activation energies of the reaction under atmospheric pressure are 41 kJ/mol and 53 kJ/mol, respectively. The leaching is mainly goethite under normal pressure, and chromite, magnetite and other mineral phases under high pressure.

The leaching of manganese from electrolytic manganese residue with sulfuric acid was studied, and the process parameters were optimized by single factor test and orthogonal test. The phase, structure, morphology and leaching kinetics of electrolytic manganese residue before and after leaching were analyzed. The leaching model was established and the leaching mechanism was explored. The results show that under the optimal conditions of particle size of 200 mesh, stirring speed of 400 r/min, leaching temperature of 95 ℃, sulfuric acid concentration of 1.5 mol/L, leaching time of 120 min and liquid volume/solid mass ratio of 11/1, the leaching rate of Mn can reach 97.90%. Manganese leaching kinetics accords with the liquid-solid shrinkage model and is controlled by chemical reaction. In the process of manganese leaching, the leaching rate of Mn can be improved by controlling the liquid volume/solid mass ratio and temperature.