The Experts below are selected from a list of 222 Experts worldwide ranked by ideXlab platform
David Dreisinger - One of the best experts on this subject based on the ideXlab platform.
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solvent extraction of silver and gold from alkaline Cyanide Solution with lix 7950
Mineral Processing and Extractive Metallurgy Review, 2014Co-Authors: Diankun Lu, Hongying Yang, David DreisingerAbstract:The cyanidation process is still the dominant technique for gold ore treatment. In this study, the potential use of the guanidine extractant LIX 7950 for recovering silver and gold from alkaline Cyanide Solution was investigated. The results indicate that LIX 7950 can effectively and efficiently extract silver and gold from their Cyanide Solution. The extraction of silver and gold with the extractant is favorable at low pH. High Cyanide to silver ratio tends to suppress silver loading while Cyanide concentration exhibits insignificant effect on gold extraction. The extraction of the mixture Solution of metal Cyanide complexes with the extractant indicated an extraction sequence of Au >A g > Zn > Ni > Cu > Fe. The loaded silver and gold can be stripped off efficiently with moderate strong NaOH Solutions at the presence of small amount of NaCN. The important findings in the research suggest that the extractant can be potentially used to recover silver and gold from alkaline Cyanide leachate and the barren c...
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A Review on Recovery of Copper and Cyanide From Waste Cyanide Solutions
Mineral Processing and Extractive Metallurgy Review, 2013Co-Authors: David Dreisinger, Fiona M. DoyleAbstract:The mainstream technology for leaching gold from gold ore is still leaching in aqueous alkaline Cyanide Solution. However, when copper minerals are present in the gold ore, high levels of free Cyanide must be maintained during leaching because many common copper minerals react with Cyanide, forming copper Cyanide complexes that deplete the Solution of free Cyanide. This results in a significant economical penalty through excessive Cyanide consumption and loss of valuable copper in tails. Environmental constraints controlling the discharge of Cyanide from mining industry are being tightened by local governments worldwide. The Solution chemistry of copper in Cyanide Solution and various technologies for the recovery of copper and Cyanide from barren gold Cyanide Solutions were reviewed in the paper. Direct recovery methods are mainly based on the acidification–volatilization–reneutralization (AVR) process or its modifications. These processes are not very efficient for treating low Cyanide Solutions and hig...
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copper solvent extraction from alkaline Cyanide Solution with guanidine extractant lix 7950
Transactions of Nonferrous Metals Society of China, 2010Co-Authors: David DreisingerAbstract:The use of the guanidine extractant LIX 7950 extracting copper and Cyanide from alkaline Cyanide Solution was investigated. The extraction of copper and Cyanide under different initial copper and extractant concentrations was examined and the stoichiometric extraction constant of Cu(CN)3 2− with LIX 7950 was calculated. Both the distribution coefficient and the stoichiometric extraction constant of Cu(CN)3 2− with LIX 7950 decrease when the temperature is varied from 25 ℃ to 45 ℃, indicating the extraction process is exothermic. The calculated enthalpy change of the reaction (ΔH Θ ) is about −190 kJ/mol. The copper extraction isotherms under different molar ratios of Cyanide to copper are established. The preferential extraction of Cu(CN)3 2− over Cu(CN)4 3− and CN − has been confirmed and a high Cyanide-to-copper molar ratio tends to suppress copper loading. The loaded copper and Cyanide can be stripped efficiently by the moderately strong NaOH Solutions (0.5−1.0 mol/L) and the
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studies on solvent extraction of copper and Cyanide from waste Cyanide Solution
Journal of Hazardous Materials, 2009Co-Authors: David DreisingerAbstract:Abstract The recovery of copper and Cyanide from waste Cyanide Solution with the guanidine extractant (LIX 7950) and the modified amine extractant (LIX 7820) has been investigated. Copper can be effectively extracted from alkaline Cyanide Solutions by both extractants. The free Cyanide remains in the aqueous phase due to the preferential extraction of Cu(CN)32− over Cu(CN)43− and CN− by the extractants. The selectivity of the metals with the extractants under different Cyanide levels has been examined. High Cyanide levels tend to depress extraction of copper and silver Cyanides, but exhibit insignificant effect on extraction of gold, zinc, nickel and iron Cyanides. A possible Solution to the separation of copper Cyanides and free Cyanide in Cyanide effluents has been suggested, by which copper can be concentrated into a small volume of Solution and the barren Cyanide Solution recycled to the cyanidation process.
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copper solvent extraction from waste Cyanide Solution with lix 7820
Solvent Extraction and Ion Exchange, 2009Co-Authors: David DreisingerAbstract:The use of a solvent mixture of a quaternary amine and nonylphenol (LIX 7820) to extract copper Cyanide from waste Cyanide Solution has been studied. Copper extraction is favorable at low pH, whereas a high Cyanide‐to‐copper ratio tends to suppress copper loading. The preferential extraction of Cu(CN)3 2− over Cu(CN)4 3− and CN− has been confirmed by the examination of both the extraction of copper and Cyanide by the solvent mixture under different experimental conditions. The solvent mixture also strongly extracted zinc and nickel from the Cyanide Solution, but it exhibits weak affinity for iron Cyanide complex and free Cyanide. The important findings suggested the potential application of the solvent mixture for the recovery of copper and Cyanide from waste Cyanide Solutions, by which copper can be extracted and concentrated into a small volume of Solution and the barren Cyanide Solution recycled to the cyanidation process.
Pan Lu - One of the best experts on this subject based on the ideXlab platform.
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solvent extraction of gold i from alkaline Cyanide Solution by dibutylcarbitol dbc with n octanol
Journal of Chemical Technology & Biotechnology, 2008Co-Authors: Pan LuAbstract:BACKGROUND: Currently, cyanidisation is preferred for the extraction of gold because it has a number of advantages over other methods. Gold(I) can be extracted with various extractants, but there are no reports on the extraction of gold(I) from Cyanide Solution by dibutylcarbitol (DBC). In this work the extraction of gold(I) from alkaline Cyanide Solution using DBC with n-octanol was studied. Several factors affecting the percentage extraction of gold(I), including DBC concentration, diluent concentration, equilibrium time, phase ratio, pH and gold concentration in aqueous phase, were investigated. RESULTS: The results showed that 96.2% of gold(I) could be extracted using an organic phase composed of 40% (v/v) DBC, 50% (v/v) n-octanol and 10% (v/v) odourless kerosene. The extraction was quite fast and equilibrium could be established within 2 min. Stripping of the gold-laden organic phase was carried out using sodium sulfite (Na2SO3) and sodium thiosulfate (Na2S2O3) Solutions, with Na2S2O3 proving better than Na2SO3. The percentage stripping of gold(I) was 96.5% when the Na2S2O3 concentration was 4% (w/w), and the stripping capacity of gold(I) exceeded 311.3 mg L−1 when the phase ratio (A/O) was equal to 0.2. CONCLUSION: Gold(I) can be extracted from aqueous Cyanide Solution by DBC in the presence of n-octanol and efficiently stripped by aqueous Na2S2O3 Solution. This method has the potential for practical application in the extraction and separation of gold. Copyright © 2008 Society of Chemical Industry
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Solvent extraction of gold(I) from alkaline Cyanide Solution by dibutylcarbitol (DBC) with n‐octanol
Journal of Chemical Technology & Biotechnology, 2008Co-Authors: Pan LuAbstract:BACKGROUND: Currently, cyanidisation is preferred for the extraction of gold because it has a number of advantages over other methods. Gold(I) can be extracted with various extractants, but there are no reports on the extraction of gold(I) from Cyanide Solution by dibutylcarbitol (DBC). In this work the extraction of gold(I) from alkaline Cyanide Solution using DBC with n-octanol was studied. Several factors affecting the percentage extraction of gold(I), including DBC concentration, diluent concentration, equilibrium time, phase ratio, pH and gold concentration in aqueous phase, were investigated. RESULTS: The results showed that 96.2% of gold(I) could be extracted using an organic phase composed of 40% (v/v) DBC, 50% (v/v) n-octanol and 10% (v/v) odourless kerosene. The extraction was quite fast and equilibrium could be established within 2 min. Stripping of the gold-laden organic phase was carried out using sodium sulfite (Na2SO3) and sodium thiosulfate (Na2S2O3) Solutions, with Na2S2O3 proving better than Na2SO3. The percentage stripping of gold(I) was 96.5% when the Na2S2O3 concentration was 4% (w/w), and the stripping capacity of gold(I) exceeded 311.3 mg L−1 when the phase ratio (A/O) was equal to 0.2. CONCLUSION: Gold(I) can be extracted from aqueous Cyanide Solution by DBC in the presence of n-octanol and efficiently stripped by aqueous Na2S2O3 Solution. This method has the potential for practical application in the extraction and separation of gold. Copyright © 2008 Society of Chemical Industry
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Performance of MSO-TBP on Synergic Extraction Gold from Cyanide Solution
Nonferrous Metals, 2006Co-Authors: Pan LuAbstract:The gold extraction process from alkaline Cyanide Solution with the synergic system consisted of MSO and TBP is studied.By the experimental results,there is the obvious synergic effect in this MSO and TBP system for gold extraction from alkaline Cyanide Solution.The maximum synergic coefficient,165,is achieved at 0.8 of the molar fraction of MSO,The gold extraction is quickly in this synergic system,the extracting equilibrium can be built within 2 minutes.Even in low phase ratio,the gold extraction rate is still high,the gold extracting recovery is up to 94.7% at phase ratio(O/A) 0.6.The alcoholic H in long-chain molecule is of remarkably effect on the gold extraction,however,it only plays an assistant role in extraction process.
Eringathodi Suresh - One of the best experts on this subject based on the ideXlab platform.
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Specific Recognition and Sensing of CN− in Sodium Cyanide Solution
Organic Letters, 2010Co-Authors: Sukdeb Saha, Amrita Ghosh, Prasenjit Mahato, Sandhya Mishra, Sanjiv K Mishra, Eringathodi SureshAbstract:Specific recognition of CN− in sodium Cyanide Solution was achieved using two imidazole-based receptors (A and B). Visually detectable color changes were associated with the formation of hydrogen bonded adducts, A·CN− and B·CN−. Ratiometric fluorescence response was achieved for receptor A on binding to CN−, and this reagent was used for imaging bacterial cells pre-exposed to 1.42 μM CN− Solution.
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specific recognition and sensing of cn in sodium Cyanide Solution
Organic Letters, 2010Co-Authors: Sukdeb Saha, Amrita Ghosh, Prasenjit Mahato, Sandhya Mishra, Sanjiv K Mishra, Eringathodi SureshAbstract:Specific recognition of CN− in sodium Cyanide Solution was achieved using two imidazole-based receptors (A and B). Visually detectable color changes were associated with the formation of hydrogen bonded adducts, A·CN− and B·CN−. Ratiometric fluorescence response was achieved for receptor A on binding to CN−, and this reagent was used for imaging bacterial cells pre-exposed to 1.42 μM CN− Solution.
Sukdeb Saha - One of the best experts on this subject based on the ideXlab platform.
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Specific Recognition and Sensing of CN− in Sodium Cyanide Solution
Organic Letters, 2010Co-Authors: Sukdeb Saha, Amrita Ghosh, Prasenjit Mahato, Sandhya Mishra, Sanjiv K Mishra, Eringathodi SureshAbstract:Specific recognition of CN− in sodium Cyanide Solution was achieved using two imidazole-based receptors (A and B). Visually detectable color changes were associated with the formation of hydrogen bonded adducts, A·CN− and B·CN−. Ratiometric fluorescence response was achieved for receptor A on binding to CN−, and this reagent was used for imaging bacterial cells pre-exposed to 1.42 μM CN− Solution.
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specific recognition and sensing of cn in sodium Cyanide Solution
Organic Letters, 2010Co-Authors: Sukdeb Saha, Amrita Ghosh, Prasenjit Mahato, Sandhya Mishra, Sanjiv K Mishra, Eringathodi SureshAbstract:Specific recognition of CN− in sodium Cyanide Solution was achieved using two imidazole-based receptors (A and B). Visually detectable color changes were associated with the formation of hydrogen bonded adducts, A·CN− and B·CN−. Ratiometric fluorescence response was achieved for receptor A on binding to CN−, and this reagent was used for imaging bacterial cells pre-exposed to 1.42 μM CN− Solution.
Faiz Bukhari Mohd Suah - One of the best experts on this subject based on the ideXlab platform.
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a closed loop electrogenerative recycling process for recovery of silver from a diluted Cyanide Solution
RSC Advances, 2019Co-Authors: Faiz Bukhari Mohd Suah, Nadia Mansor, Hairul Hisham Hamzah, Norita MohamedAbstract:A closed-loop process for the complete recovery of silver from a diluted silver Cyanide Solution has been constructed based on an electrogenerative process. It was shown that the reduction of silver was a mass transport controlled process. Under optimal experimental conditions, 100% of silver was recovered from 500 mg L−1 and 100 mg L−1 silver Cyanide Solutions by using a reticulated vitreous electrode (RVC) as the cathode. The Cyanide Solution was recycled and reused so that a closed-loop process was obtained. In addition, the RVC in this study can be used repeatedly up to 10 cycles with a calculated relative standard deviation of 1.90%.
