The adsorption behaviors and mechanisms of gold from thiosulfate solution on strong-base anion exchange resin were systematically investigated.The comparison experiment of adsorption ability and selectivity for gold s...The adsorption behaviors and mechanisms of gold from thiosulfate solution on strong-base anion exchange resin were systematically investigated.The comparison experiment of adsorption ability and selectivity for gold showed that gel Amberlite IRA-400 resin with Type Ⅰ quaternary ammonium functional group had better adsorption performance.The increases of resin dosage,ammonia concentration and solution pH were favorable to gold adsorption,whereas the rises of cupric and thiosulfate concentrations were disadvantageous to gold loading.Microscopic characterization results indicated that gold was adsorbed in the form of [Au(S_(2)O_(3))_(2)]^(3–) complex anion by exchanging with the counter ion Cl^(–) in the functional group of the resin.Density functional theory calculation result manifested that gold adsorption was mainly depended on the hydrogen bond and van der Waals force generated between O atom in [Au(S_(2)O_(3))_(2)]^(3–) and H atom in the quaternary ammonium functional group of the resin.展开更多
A gold leaching process by using in situ oxidation products of added elemental sulfur in Ca(OH)2 solution was investigated. A gold concentrate containing 45 g/t Au was tested and 85%~87% of gold were leached. The leac...A gold leaching process by using in situ oxidation products of added elemental sulfur in Ca(OH)2 solution was investigated. A gold concentrate containing 45 g/t Au was tested and 85%~87% of gold were leached. The leached gold depends mainly on the initial molar ratio of elemental sulfur to the hydroxyl ion, the consumption of oxygen and the reaction temperature. Adding some surfactants, such as lignosulfonic calcium, at lower concentration increased the leached Au but at higher concentration decreased it. Both of thermodynamic analysis and experimental results show that thiosulfate is the major complexing agent for gold in the process.展开更多
A gold leaching process by using oxidation products of elemental sulfur in alkaline solutions was proposed and investigated. A gold concentrate and a residue from an arsenic refractory gold concentrate by acidic oxida...A gold leaching process by using oxidation products of elemental sulfur in alkaline solutions was proposed and investigated. A gold concentrate and a residue from an arsenic refractory gold concentrate by acidic oxidation leaching were tested. The residue contains 16.3% elemental sulfur and no more elemental sulfur was added in tests. For the concentrate elemental sulfur was added before leaching tests. The leaching ratio of gold depends mainly on the initial equivalent ratio of elemental sulfur to hydroxyl ions, the consumption of oxygen and the reaction temperature in the process. Analysis of the experimental results shows that thiosulfate is the majority complexing reagent for gold in the process. Over 90% gold was leached from the residue and 82%87% from the concentrate by using this process.展开更多
基金the financial support from the Natural Science Foundation of Hunan Province, China (No. 2023JJ40723)China Postdoctoral Science Foundation (No. 2022M723549)the National Natural Science Foundation of China (Nos. 52174271, 51504293)。
文摘The adsorption behaviors and mechanisms of gold from thiosulfate solution on strong-base anion exchange resin were systematically investigated.The comparison experiment of adsorption ability and selectivity for gold showed that gel Amberlite IRA-400 resin with Type Ⅰ quaternary ammonium functional group had better adsorption performance.The increases of resin dosage,ammonia concentration and solution pH were favorable to gold adsorption,whereas the rises of cupric and thiosulfate concentrations were disadvantageous to gold loading.Microscopic characterization results indicated that gold was adsorbed in the form of [Au(S_(2)O_(3))_(2)]^(3–) complex anion by exchanging with the counter ion Cl^(–) in the functional group of the resin.Density functional theory calculation result manifested that gold adsorption was mainly depended on the hydrogen bond and van der Waals force generated between O atom in [Au(S_(2)O_(3))_(2)]^(3–) and H atom in the quaternary ammonium functional group of the resin.
基金Supported by the National Natural Science Foundation of China (No.: 59674025)
文摘A gold leaching process by using in situ oxidation products of added elemental sulfur in Ca(OH)2 solution was investigated. A gold concentrate containing 45 g/t Au was tested and 85%~87% of gold were leached. The leached gold depends mainly on the initial molar ratio of elemental sulfur to the hydroxyl ion, the consumption of oxygen and the reaction temperature. Adding some surfactants, such as lignosulfonic calcium, at lower concentration increased the leached Au but at higher concentration decreased it. Both of thermodynamic analysis and experimental results show that thiosulfate is the major complexing agent for gold in the process.
文摘A gold leaching process by using oxidation products of elemental sulfur in alkaline solutions was proposed and investigated. A gold concentrate and a residue from an arsenic refractory gold concentrate by acidic oxidation leaching were tested. The residue contains 16.3% elemental sulfur and no more elemental sulfur was added in tests. For the concentrate elemental sulfur was added before leaching tests. The leaching ratio of gold depends mainly on the initial equivalent ratio of elemental sulfur to hydroxyl ions, the consumption of oxygen and the reaction temperature in the process. Analysis of the experimental results shows that thiosulfate is the majority complexing reagent for gold in the process. Over 90% gold was leached from the residue and 82%87% from the concentrate by using this process.
