The solid sodium hydroxide neutralized acidic As-containing wastewater till pH value was 6.Green copper arsenite was prepared after copper sulfate was added into the neutralized wastewater when the molar ratio of Cu t...The solid sodium hydroxide neutralized acidic As-containing wastewater till pH value was 6.Green copper arsenite was prepared after copper sulfate was added into the neutralized wastewater when the molar ratio of Cu to As was 2:1 and pH value of the neutralized wastewater was adjusted to 8.0 by sodium hydroxide.The arsenious acid solution and red residue were produced after copper arsenite mixed with water according to the ratio of liquid to solid of 4:1 and copper arsenite was reduced by SO2 at 60℃for 1 h.The white powder was gained after the arsenious acid solution was evaporated and cooled.Copper sulfate solution was obtained after the red residue was leached by H2SO4 solution under the action of air.The results show that red residue is Cu3(SO3)2·2H2O and the white powder is As2O3.The leaching rate of Cu reaches 99.00%when the leaching time is 1.5 h,molar ratio of H2SO4 to Cu is 1.70,H2SO4 concentration is 24%and the leaching temperature is 80℃.The direct recovery rate of copper sulfate is 79.11%and the content of CuSO4·5H2O is up to 98.33%in the product after evaporating and cooling the copper sulfate solution.展开更多
The preparation of granulated adsorption material of water-quenched slag/rectorite composite and the treatment of Cu ( Ⅱ )-containing copper smelter wastewater with the adsorption material were studied. The experim...The preparation of granulated adsorption material of water-quenched slag/rectorite composite and the treatment of Cu ( Ⅱ )-containing copper smelter wastewater with the adsorption material were studied. The experimental results showed that under the conditions with the mass ratio of water-quenched slag to rectorite of 1:1, 10% additive of industrial starch (IS), and 50% water, and a calcination temperature of 400 ℃, the granulated adsorption material prepared had a density of 1.06 kg/m^3, a porosity of 62.29%, water absorption rate of 58.82%, and compressive strength of 2.22 MPa. The efficiency of wastewater treatment was the best, whereas the rate of spallation loss was low. Under the conditions of natural pH, with the addition of the granulated adsorption material of 0.05 g/mL, a reaction time of 40 minutes, and temperature of 25 ℃, the efficiency of the granulated adsorption material for the removal of Cu ( Ⅱ ) ions from the copper smelter wastewater attained 98.2%, and the quality indexes of the wastewater after treatment conformed with the first level of integrated wastewater discharge standard (GB8978-1996). The reclamation of the used granulated adsorption material was carried out by de-sorption of the Cu ( Ⅱ) ions from the surface with 1 mol/L sodium chloride solution. The de-sorption rate was 96.4%, and the adsorption material can be reused many times to treat copper smelter wastewater.展开更多
The enrichment of copper from copper–cyanide wastewater by solvent extraction was investigated using a quaternary ammonium salt as an extractant. The influences of important parameters, e.g., organic-phase components...The enrichment of copper from copper–cyanide wastewater by solvent extraction was investigated using a quaternary ammonium salt as an extractant. The influences of important parameters, e.g., organic-phase components, aqueous pH values, temperature, inorganic anion impurities, CN/Cu molar ratio, and stripping reagents, were examined systematically, and the optimal conditions were determined. The results indicated that copper was effectively concentrated from low-concentration solutions using Aliquat 336 and that the extraction efficiency increased linearly with increasing temperature. The aqueous pH value and concentrations of inorganic anion impurities only weakly affected the extraction process when varied in appropriate ranges. The CN/Cu molar ratio affected the extraction efficiency by changing the distribution of copper–cyanide complexes. The difference in gold leaching efficiency between using raffinate and fresh water was negligible.展开更多
Bone charcoal (BC) is being developed as a treatment for decontamination of polluted water. In this study, bone charcoal was obtained by pyrolysis of cow bones and tested for the elimination of copper from aqueous sol...Bone charcoal (BC) is being developed as a treatment for decontamination of polluted water. In this study, bone charcoal was obtained by pyrolysis of cow bones and tested for the elimination of copper from aqueous solutions. The minimum time to reach the removal equilibrium by adsorption was 10 min with a maximum of copper removal equal to 9615 mg/g. Different kinetics models were applied to fit the experimental data: the pseudo second-order model correlated the results with a linear correlation coefficient equal to 1.展开更多
文摘The solid sodium hydroxide neutralized acidic As-containing wastewater till pH value was 6.Green copper arsenite was prepared after copper sulfate was added into the neutralized wastewater when the molar ratio of Cu to As was 2:1 and pH value of the neutralized wastewater was adjusted to 8.0 by sodium hydroxide.The arsenious acid solution and red residue were produced after copper arsenite mixed with water according to the ratio of liquid to solid of 4:1 and copper arsenite was reduced by SO2 at 60℃for 1 h.The white powder was gained after the arsenious acid solution was evaporated and cooled.Copper sulfate solution was obtained after the red residue was leached by H2SO4 solution under the action of air.The results show that red residue is Cu3(SO3)2·2H2O and the white powder is As2O3.The leaching rate of Cu reaches 99.00%when the leaching time is 1.5 h,molar ratio of H2SO4 to Cu is 1.70,H2SO4 concentration is 24%and the leaching temperature is 80℃.The direct recovery rate of copper sulfate is 79.11%and the content of CuSO4·5H2O is up to 98.33%in the product after evaporating and cooling the copper sulfate solution.
基金Supported by the National Key Technologies Research and Development Program of China during the 1 lth Five-Year Plan Period (2007BAB22B01) and the Young Science Foundation of Jiangxi Province Education Office (GJJ11124).
基金National"973"Plan Research Project(No.2004CB619204)Educational Ministry Scientific and Technological Research Key Project(No.02052)
文摘The preparation of granulated adsorption material of water-quenched slag/rectorite composite and the treatment of Cu ( Ⅱ )-containing copper smelter wastewater with the adsorption material were studied. The experimental results showed that under the conditions with the mass ratio of water-quenched slag to rectorite of 1:1, 10% additive of industrial starch (IS), and 50% water, and a calcination temperature of 400 ℃, the granulated adsorption material prepared had a density of 1.06 kg/m^3, a porosity of 62.29%, water absorption rate of 58.82%, and compressive strength of 2.22 MPa. The efficiency of wastewater treatment was the best, whereas the rate of spallation loss was low. Under the conditions of natural pH, with the addition of the granulated adsorption material of 0.05 g/mL, a reaction time of 40 minutes, and temperature of 25 ℃, the efficiency of the granulated adsorption material for the removal of Cu ( Ⅱ ) ions from the copper smelter wastewater attained 98.2%, and the quality indexes of the wastewater after treatment conformed with the first level of integrated wastewater discharge standard (GB8978-1996). The reclamation of the used granulated adsorption material was carried out by de-sorption of the Cu ( Ⅱ) ions from the surface with 1 mol/L sodium chloride solution. The de-sorption rate was 96.4%, and the adsorption material can be reused many times to treat copper smelter wastewater.
文摘The enrichment of copper from copper–cyanide wastewater by solvent extraction was investigated using a quaternary ammonium salt as an extractant. The influences of important parameters, e.g., organic-phase components, aqueous pH values, temperature, inorganic anion impurities, CN/Cu molar ratio, and stripping reagents, were examined systematically, and the optimal conditions were determined. The results indicated that copper was effectively concentrated from low-concentration solutions using Aliquat 336 and that the extraction efficiency increased linearly with increasing temperature. The aqueous pH value and concentrations of inorganic anion impurities only weakly affected the extraction process when varied in appropriate ranges. The CN/Cu molar ratio affected the extraction efficiency by changing the distribution of copper–cyanide complexes. The difference in gold leaching efficiency between using raffinate and fresh water was negligible.
文摘Bone charcoal (BC) is being developed as a treatment for decontamination of polluted water. In this study, bone charcoal was obtained by pyrolysis of cow bones and tested for the elimination of copper from aqueous solutions. The minimum time to reach the removal equilibrium by adsorption was 10 min with a maximum of copper removal equal to 9615 mg/g. Different kinetics models were applied to fit the experimental data: the pseudo second-order model correlated the results with a linear correlation coefficient equal to 1.