precipitating gold from sodium thiosulfate with sodium sulfide
2019-04-29T08:04:02+00:00
Thiosulfate leaching of gold—A review ScienceDirect
Electrochemical impedence spectral studies have shown that gold passivation can occur in the absence of copper (MacDonald, 1990) The appearance of an inductive arc in the potential range of gold dissolution in sodium thiosulfate solution is assigned to the passivation of the gold electrode accompanying its dissolution On an industrial scale, sodium thiosulfate is produced chiefly from liquid waste products of sodium sulfide or sulfur dye manufacture[2] In the laboratory, this salt can be prepared by heating an aqueous solution of sodium sulfite with sulfur or by boiling aqueous sodium hydroxide and sulfur according with the following equation:[3]a new plan Gold Refining ForumA process for recovering gold from thiosulfate leach solutions and slurries in which gold is loaded onto an ion exchange resin Gold is recovered from the resin by elution with polythionate ions and the resin is regenerated with sulfide or sulfite Gold is recovered from the eluate by precipitation with sulfide ions, cementation or electrowinningCAC A process for recovering gold from
Thiosulfate Questions and Discussion Page 2 Gold
We want to use sodium thiosulfate as a leach for ore crushed down to 150 mesh that contains (tested) microscopic gold, a little free gold that's too small to pick out with your fingers, and silver We have sodium thiosulfate in crystal form from a chemical company, but don't know the water to chemical ratio for putting it into solutionThe gold ore designated Sample C was subjected to thiosulfate leaching under oxygen pressure at varying initial sodium thiosulfate concentrations Samples of the ore were prepared and leached as described in Example 3 except the temperature was maintained at 60° C in each test and the initial sodium thiosulfate concentration was variedMethod for thiosulfate leaching of precious metal Sodium hydroxide solution was prepared by dissolving solid sodium hydroxide in deionized water, and it was used as the pH adjustment solution in the thiosulfate precipitation experiments The preparation of selenosulfate solution was achieved by dissolving selenium powder (Alfa Aesar Chemical selenium powder, 325 mesh, 995%) in hot sulfite An investigation of mercury stabilization techniques
USB2 Method for thiosulfate leaching of
Processes are provided for recovering precious metals from refractory materials using thiosulfate lixiviants The processes can employ lixiviants that include at most only small amounts of copper and/or ammonia and operate at a relatively low pH, reduction of polythionates, inert atmospheres to control polythionate production, and electrolytic solutions which provide relatively high rates of The products in solution as a result of the sodium sulfide leach reaction include sodium thioantimonite and sodium thioarsenite, along with some mercury and gold This solution is contacted with elemental sulfur at a temperature of about 80° C in order to produce sodium thioantimonate and sodium Sodium sulfide leach process Equity Mining Sodium thiosulfate reacts with hydrochloric acid to form sulfur and sulfur dioxide (Equation 1) Na 2 S 2 O 3 (aq) + 2HCl(aq)→ S(s) + 2 SO(g) + 2NaCl(aq) Equation 1 The kinetics of the reaction can be analyzed by graphing the concentration of Na 2 S 2 O 3 as a function of both reaction time andRate of Reaction of Sodium Thiosulfate and Hydrochloric
a new plan Gold Refining Forum
On an industrial scale, sodium thiosulfate is produced chiefly from liquid waste products of sodium sulfide or sulfur dye manufacture[2] In the laboratory, this salt can be prepared by heating an aqueous solution of sodium sulfite with sulfur or by boiling aqueous sodium hydroxide and sulfur according with the following equation:[3] Your Gold Recovery Kit Includes 500g bottle of Sodium Metabisulfite NC10319 500g bottle of Urea NC2620 Sodium metabisulfite is commonly used to precipitate dissolved gold out of aqua regia and gold chloride solutions When it is dissolved into water sulfur dioxide gas is created which is excellent at precipitating gold from the solutiongold extraction for urea sodium metabisulfite ratio in fiji Cyanidation is a hydrometallurgical process in which precious metals (gold and silver) are dissolved from the ore by solutions of sodium cyanide or potassium cyanide (HHE 1988; US EPA 1994)The cyanide heap leaching is mainly used for the recovery of gold from lowgrade ore, while leaching in the reactor is used for higher grade ore (US EPA 1994)Biorecovery of nanogold and nanogold compounds
A Method for Leaching or Dissolving Gold from Ores or
native gold from goldbearing ores or the dissolution of gold metal during the recycling of electronic and precious metal scrap is performed every day using hazardous chemicals such as sodium cyanide or aqua regia These chemicals represent health and safety risks for workers and a serious threat for the environment However, even if several Restrictive requirements for maximum concentrations of metals introduced into the environment lead to search for effective methods of their removal Chemical precipitation using hydroxides or sulfides is one of the most commonly used methods for removing metals from water and wastewater The process is simple and inexpensive However, during metal hydroxide precipitation, Removal of Heavy Metal Ions from Water and Sodium sulfide or yellow sodium polysulfide Yellow sodium polysulfide is used to dissolve sulfides of metals including gold sulfide (Au2S) If in the patent, sodium sulfide was used to precipitate gold sulfide, they first acidified the solution to pH3 with Sulfuric acid or with hydrochloric acid Concerning the steel wool, don't change the pHThiosulphate DroppedTesting for PM? Page 2
Precipitation reactions Reactions in aqueous solution
Salt Solubility Nitrates All are soluble Potassium, sodium and ammonium salts All are soluble Chlorides, bromides and iodides All are soluble except silver, lead(II) and mercury(II) salts (eg silver chloride) Sulphates All are soluble except lead(II) sulphate, barium sulphate and calcium sulphate Carbonates All are insoluble except those of potassium, sodium and ammoniumA sodium sulfate smelting process for treating complex antimony ore concentrate includes such steps as smelting with sodium sulfate, extracting, settling antimony and removing iron to obtain sodium antimonate and other valuable metal (Pb and Au) ore concentrates, and features great reduction of treatment cost, thorough separation of Sb, As, Pb, or Ag from each other, effectively increasing the CNA Method for smelting sodium sulfate So I was doing electrolysis on two silver electrodes and sodium thiosulfate Some observations The voltage drops extremely fast from 2 V to less than 1 V in 15 minutes, possibly because of the thiosulfate reduction Gases are liberated out of solution The solution turns black quickly Alert: I am using a fume hoodForming hydrogen sulfide from electrolysis of sodium
Composition and process for printed circuit etching
Example 2 was repeated with essentially no sodium in the solution except for solution concentrations of 38% hydrogen peroxide, 121% sulfuric acid, and the sodium thiosulfate was replaced with 1 g/l ammonium thiosulfate The etch time was determined when 98 g/l copper had accumulated and the results are reported in Table I as Example 3AThe role of ligands and oxidants in thiosulfate leaching of gold (iv) the effect of particular minerals to adsorb or precipitate gold and/or Despite the fact that the gold mining industry 03 M sodium thiosulfate and 3 M ammonia (pH 102) in the extraction of gold and silver from complex sulfide ores bycaustic soda and sodium thiosulfate leach for gold On an industrial scale, sodium thiosulfate is produced chiefly from liquid waste products of sodium sulfide or sulfur dye manufacture[2] In the laboratory, this salt can be prepared by heating an aqueous solution of sodium sulfite with sulfur or by boiling aqueous sodium hydroxide and sulfur according with the following equation:[3]a new plan Gold Refining Forum
Biorecovery of nanogold and nanogold compounds
Cyanidation is a hydrometallurgical process in which precious metals (gold and silver) are dissolved from the ore by solutions of sodium cyanide or potassium cyanide (HHE 1988; US EPA 1994)The cyanide heap leaching is mainly used for the recovery of gold from lowgrade ore, while leaching in the reactor is used for higher grade ore (US EPA 1994) native gold from goldbearing ores or the dissolution of gold metal during the recycling of electronic and precious metal scrap is performed every day using hazardous chemicals such as sodium cyanide or aqua regia These chemicals represent health and safety risks for workers and a serious threat for the environment However, even if severalA Method for Leaching or Dissolving Gold from Ores or The gold sulfide concentrate is obtained after flotation The grades are: gold 1115 g/t, silver 4317 g/t, copper 018%, aluminum 005%, sulfur 2526%, carbon 154% The recovery rate of gold flotation is 96% The goldcontaining sulfur concentrate is leached by a agitation leaching systemThe Ultimate Guide to Gold Cyanidation
Thiosulphate DroppedTesting for PM? Page 2
Sodium sulfide or yellow sodium polysulfide Yellow sodium polysulfide is used to dissolve sulfides of metals including gold sulfide (Au2S) If in the patent, sodium sulfide was used to precipitate gold sulfide, they first acidified the solution to pH3 with Sulfuric acid or with hydrochloric acid Concerning the steel wool, don't change the pH Processes are provided for recovering precious metals from refractory materials using thiosulfate lixiviants The processes can employ lixiviants that include at most only small amounts of copper and/or ammonia and operate at a relatively low pH, reduction of polythionates, inert atmospheres to control polythionate production, and electrolytic solutions which provide relatively high rates of US Patent for Method for thiosulfate leaching of Salt Solubility Nitrates All are soluble Potassium, sodium and ammonium salts All are soluble Chlorides, bromides and iodides All are soluble except silver, lead(II) and mercury(II) salts (eg silver chloride) Sulphates All are soluble except lead(II) sulphate, barium sulphate and calcium sulphate Carbonates All are insoluble except those of potassium, sodium and ammoniumPrecipitation reactions Reactions in aqueous solution
Forming hydrogen sulfide from electrolysis of sodium
So I was doing electrolysis on two silver electrodes and sodium thiosulfate Some observations The voltage drops extremely fast from 2 V to less than 1 V in 15 minutes, possibly because of the thiosulfate reduction Gases are liberated out of solution The solution turns black quickly Alert: I am using a fume hood The resulting sodium aluminate combines with water to form a hydrate, returning to the solution some of its alkalinity: 8NaAlO 2 + 16H 2 O ⇒ 8NaOH + 4Al 2 O 3 •3H 2 O(s) Caustic with coppercontaining phases Aerospace aluminum is commonly an alloy, and a formulated alkaline solution containing sodium sulfide will likely react with the Aluminum Surface Finishing Corrosion Causes and