Based on the properties of antimony(Sb)and arsenic(As),a method was proposed to enhance gold recovery during iron matte smelting.The impact of Sb and As on gold enhancement capture was investigated using an exclusion ...Based on the properties of antimony(Sb)and arsenic(As),a method was proposed to enhance gold recovery during iron matte smelting.The impact of Sb and As on gold enhancement capture was investigated using an exclusion method.The results demonstrated that both Sb and As significantly improved the gold recovery rate.As the Sb or As content increased,the gold recovery rate increased.The enhancement effect of Sb was better than that of As,and the optimal results were achieved through the synergistic effects of Sb and As.Under optimized conditions,the gold recovery rate reached 97.12%,whereas the gold content in the slag decreased to 1.70 g/t.Sb captured and aggregated free gold as an Au-Sb alloy,whereas As-Fe alloy also captured free gold.The growth of the gold-captured phase size enhanced the settling velocity,thereby promoting gold recovery.展开更多
Applying bio-oxidation waste solution(BOS)to chemical-biological two-stage oxidation process can significantly improve the bio-oxidation efficiency of arsenopyrite.This study aims to clarify the enhanced oxidation mec...Applying bio-oxidation waste solution(BOS)to chemical-biological two-stage oxidation process can significantly improve the bio-oxidation efficiency of arsenopyrite.This study aims to clarify the enhanced oxidation mechanism of arsenopyrite by evaluating the effects of physical and chemical changes of arsenopyrite in BOS chemical oxidation stage on mineral dissolution kinetics,as well as microbial growth activity and community structure composition in bio-oxidation stage.The results showed that the chemical oxidation contributed to destroying the physical and chemical structure of arsenopyrite surface and reducing the particle size,and led to the formation of nitrogenous substances on mineral surface.These chemical oxidation behaviors effectively promoted Fe^(3+)cycling in the bio-oxidation system and weakened the inhibitory effect of the sulfur film on ionic diffusion,thereby enhancing the dissolution kinetics of the arsenopyrite.Therefore,the bio-oxidation efficiency of arsenopyrite was significantly increased in the two-stage oxidation process.After 18 d,the two-stage oxidation process achieved total extraction rates of(88.8±2.0)%,(86.7±1.3)%,and(74.7±3.0)%for As,Fe,and S elements,respectively.These values represented a significant increase of(50.8±3.4)%,(47.1±2.7)%,and(46.0±0.7)%,respectively,compared to the one-stage bio-oxidation process.展开更多
Cyanide is the most widely used reagent in gold production processes. However, cyanide is highly toxic and poses safety haz-ards during transportation and use. Therefore, it is necessary to develop gold leaching reage...Cyanide is the most widely used reagent in gold production processes. However, cyanide is highly toxic and poses safety haz-ards during transportation and use. Therefore, it is necessary to develop gold leaching reagents that can replace cyanide. This paper intro-duces a method for synthesizing a gold leaching reagent. Sodium cyanate is used as the main raw material, with sodium hydroxide and so-dium ferrocyanide used as additives. The gold leaching reagent can be obtained under the conditions of a mass ratio of sodium cyanate,sodium hydroxide, and sodium ferrocyanide of 15:3:1, synthesis temperature of 600℃, and synthesis time of 1 h. This reagent has a goodrecovery effect on gold concentrate and gold-containing electronic waste. The gold leaching rate of roasted desulfurized gold concentratecan reach 87.56%. For the extraction experiments of three types of gold-containing electronic waste, the gold leaching rate can reach over90% after 2 h. Furthermore, the reagent exhibits good selectivity towards gold. Component analysis indicates that the effective compon-ent in the reagent could be sodium isocyanate.展开更多
基金financially supported from the National Natural Science Foundation of China(No.52274358)the Natural Science Foundation of Hunan Province,China(No.2020JJ4718)+2 种基金the Major Science and Technology Projects of Gansu Province,China(No.22ZD6GC017)the Young Scientists Fund of National Natural Science Foundation of China(No.51404296)the National Key Research and Development Program of China(No.2018YFC1901604).
文摘Based on the properties of antimony(Sb)and arsenic(As),a method was proposed to enhance gold recovery during iron matte smelting.The impact of Sb and As on gold enhancement capture was investigated using an exclusion method.The results demonstrated that both Sb and As significantly improved the gold recovery rate.As the Sb or As content increased,the gold recovery rate increased.The enhancement effect of Sb was better than that of As,and the optimal results were achieved through the synergistic effects of Sb and As.Under optimized conditions,the gold recovery rate reached 97.12%,whereas the gold content in the slag decreased to 1.70 g/t.Sb captured and aggregated free gold as an Au-Sb alloy,whereas As-Fe alloy also captured free gold.The growth of the gold-captured phase size enhanced the settling velocity,thereby promoting gold recovery.
基金Project(52274348)supported by the National Natural Science Foundation of ChinaProject(2022JH1/10400024)supported by the Major Projects for the“Revealed Top”Science and Technology of Liaoning Province,China。
文摘Applying bio-oxidation waste solution(BOS)to chemical-biological two-stage oxidation process can significantly improve the bio-oxidation efficiency of arsenopyrite.This study aims to clarify the enhanced oxidation mechanism of arsenopyrite by evaluating the effects of physical and chemical changes of arsenopyrite in BOS chemical oxidation stage on mineral dissolution kinetics,as well as microbial growth activity and community structure composition in bio-oxidation stage.The results showed that the chemical oxidation contributed to destroying the physical and chemical structure of arsenopyrite surface and reducing the particle size,and led to the formation of nitrogenous substances on mineral surface.These chemical oxidation behaviors effectively promoted Fe^(3+)cycling in the bio-oxidation system and weakened the inhibitory effect of the sulfur film on ionic diffusion,thereby enhancing the dissolution kinetics of the arsenopyrite.Therefore,the bio-oxidation efficiency of arsenopyrite was significantly increased in the two-stage oxidation process.After 18 d,the two-stage oxidation process achieved total extraction rates of(88.8±2.0)%,(86.7±1.3)%,and(74.7±3.0)%for As,Fe,and S elements,respectively.These values represented a significant increase of(50.8±3.4)%,(47.1±2.7)%,and(46.0±0.7)%,respectively,compared to the one-stage bio-oxidation process.
基金financially supported by the National Natural Science Foundation of China (No.51974016)。
文摘Cyanide is the most widely used reagent in gold production processes. However, cyanide is highly toxic and poses safety haz-ards during transportation and use. Therefore, it is necessary to develop gold leaching reagents that can replace cyanide. This paper intro-duces a method for synthesizing a gold leaching reagent. Sodium cyanate is used as the main raw material, with sodium hydroxide and so-dium ferrocyanide used as additives. The gold leaching reagent can be obtained under the conditions of a mass ratio of sodium cyanate,sodium hydroxide, and sodium ferrocyanide of 15:3:1, synthesis temperature of 600℃, and synthesis time of 1 h. This reagent has a goodrecovery effect on gold concentrate and gold-containing electronic waste. The gold leaching rate of roasted desulfurized gold concentratecan reach 87.56%. For the extraction experiments of three types of gold-containing electronic waste, the gold leaching rate can reach over90% after 2 h. Furthermore, the reagent exhibits good selectivity towards gold. Component analysis indicates that the effective compon-ent in the reagent could be sodium isocyanate.
