The method of extracting gold from solutions
(57) Abstract:Use: for the extraction of gold from gold-bearing solution by sorption. Entity: recovery of gold from solutions carried out by sorption using as a sorbent of hydrated gas II patterns, with higher sorption capacity. It receives sufficient conditions for hydrate formation in the intensive mixing of fresh water with gas. Improved efficiency of extraction. 1 table, 1 Il. The invention relates to the physical chemistry of solutions and can find application in mineral processing, specifically for the recovery of precious metals from enriched concentrates, as well as for the extraction of gold from sea water and other solutions.The known method, which is widely used and implemented on the technological cycles of Ziph (1). This technology involves the leaching of the concentrate, washing gold and cyanide extraction of gold adsorption column, pre-saturated resin AM 25. However, because of the difficulty of manufacture of sorbent resins, its sorption capacity is limited. A relatively small capacity of the sorbent undergoes further ominaisuus negative impact on the development process of sorption.There is also known a method of extracting gold from solutions consisting in the adsorption of gold on polyamine (2). This method is complicated by the observance of secondary and tertiary nitrogen atoms in the structural sorbent of polyethylenimine, which determine the interval of measuring the acidity of a solution. Sorption conditions at pH 5-1 requires additional energy costs. Synthesis of nitrogen-containing hetero-chain sorbents on the basis of Iminov and guanidino different basicity requires the consumption of expensive chemical reagents, holding a thin chemical reactions with directional properties of the obtained substances and parameters of sorption complicates the technological process.The invention consists in the fact that the proposed method comprising processing the original gold-bearing solution sorbent, characterized in that before the sorption pH of the initial solution is brought to a value of 7.6, and sorption is carried out at 274 275 K, a pressure of 0.2 MPa using as adsorbent crystalline received by the fresh water connection gas gidratoobrazovaniya, size 0,22 0,4 mm Solid crystalline previously used for technological purposes for fresh water, the dehydration of gases and of oil for storage gasometric fossil, namely, for the recovery of gold from solutions were not used. Thus, the proposed solution meets the criterion of "novelty". In comparison with the known technical solutions in the proposed method the new properties are:
use as a sorbent cheap molecular compounds from local material on the basis of water (hydrated), distinguish the ease of synthesis and dissociation after the process of adsorption for water, gas and gold, which simplifies further fine-tuning of the known methods;
improving the efficiency of gold recovery due to higher sorption capacity and specific surface area of the proposed hydrated, and also due to the fact that the crystalline not absorb water, its sorption capacity is stable. Thus, the claimed method meets the criterion of "inventive step".The essence of the method is illustrated on the drawing, which shows a General flow chart of extraction of gold from solution. The crystalline get under intensive mixing of fresh water and gas under conditions sufficient for their education. Gases and liquids, in which the sizes of the molecules d>0,66 nm can not form hydrates due to steric conditions. In the event that apolnet two large and six small cavities KC-1. If gases gidratoobrazovaniya with the size of the molecules 0,501<d>is 0.59 nm (COS, (CH2)3and so on) fill only two large cavity hydrates patterns KC-1. Large molecule gases-gidratoobrazovaniya 0,59<d<0,66 nm (propane, isobutane, and others ) form a crystalline structure two (KC-2) and fill only eight large cavities hydrate. This sixteen small cavities hydrates of this structure are filled with gases with smaller molecules, i.e., less of 0.48 nm (methane, hydrogen sulfide, and others).The obtained crystals of the hydrate is cooled below 253 K for 8 to 10 h, after which they are crushed, sieved and select the faction 0,22 0,4 mm of the Crystalline fraction 1 fill pre-thermostated column 4 pressure gauge 5. The input column, fitted with a valve for regulating flow 6, connect under pressure, at which the crystalline sustainable, in the processing system for the extraction of gold from solution and thermostatic at a temperature of 274 275 K, a pressure of 0.2 MPa. Demolition of crystalline prevents safety nets 7 in the upper and lower parts of the column. To maintain a positive pressure column is provided with a check valve 8. The flow of filtrate is measured rhodometra the good ions. In crystals of gas hydrates sorption is subjected only neutral atoms, these crystals sustainability are in a neutral medium at a pH of 7.6. Therefore, the acidic solution timesaving complex is neutralized with caustic soda solution. While gold ions are restored to the neutral atom according to the scheme:
< / BR>Neutral gold atoms form in the liquid medium of the colloid-dispersed system, cleanse it from the sludge and thermostatic at 274 275 K.Molecular compounds gas with water to form a second crystal structure of the hydrate with the ideal formula 8M1x 16M2x 136 H2O, where M1and M2respectively the large and small cavities. Gas molecules fill only eight large cavities, sixteen small cavities remain free. When passing the solution through the hydrated sorbent gold atoms gradually accumulate in small cavities of the crystal structure to form a face-centered cubic structure of the fourteen atoms.Lattice parameters, particle size and degree of filling of small cavities hydrate in the table.In these tables, the degree of filling of cavities 1,0 characterizes the maximum 100%resultsstart small cavities. Each cavity may include one face-centered cubic structure of 14 gold atoms. Thus, 136 g-mol (2448 g) of water when full, cavities can absorb 224 g-atom (44 130 g) of gold. From the data, the maximum capacity of the sorbent, it follows that if one hundred free of cavities in the crystal structure of the sorbent is at least one cavity is filled recentrifuging cubic structure of gold, 2.5 kg of water can absorb 300 500 grams of gold. The dimensions of the structural units of iron, its compounds and other metals do not allow absorb in the small cavities of molecular compounds.The degree of extraction of gold from solution is increased by the repetition of cycles of sorption and increase the degree of filling of the cavities of molecular structures.Example. In the pressure vessel to control the temperature and pressure is placed 100 ml of fresh water and thermostatized at 275 K. At this temperature in the vessel is pressurized to 0.5 MPa gas. In these conditions of intense mixing system produces crystal structure of KC-2. Username crystals at subzero temperatures below 253 To fill the sorption column with a diameter of 5 mm, height 150 mm In order to create an ISI of 0.2 MT and at a pH of 7.6 is set solution flow rate 2 l/h The test was subjected to 15 grams of gold concentrate (primary bulk concentrate), the gold content in it to 17.7 g/T. After leaching in the original tiomochevina solution (1 l) contained 0,266 mg of gold, 27 g of oxides and salts of iron (magnetites). The original solution is pre-processed with alkali solution to pH of 7.6. At a temperature of 275 K, the addition of 0.2 MPa solution is passed through a sorbent for 30 min (flow rate 2 l/h). After sorption in eluent the gold content is of 0.066 mg, the content of oxides and salts of iron and 26.8 g Sorbent (hydrate) decompose and it is determined by the sorbed amount of gold (0.2 mg), the percentage of extraction 75,2, the presence of oxides and salts of iron, a small amount (about 0.2 mg). A face-centered structure of iron oxide have a size 0,839 nm that cannot fit in the available cavity hydrates (of 0.48 nm). The method of extracting gold from solutions, including sorption, characterized in that before the sorption pH of the initial solution is brought to a value equal to 7.6, and sorption is carried out at 274 275 K, 0.2 MPa using as adsorbent crystalline received by the fresh water connection gas gidratoobrazovaniya, size 0,22 0,4 mm
FIELD: noble metal hydrometallurgy.
SUBSTANCE: invention relates to method for acid leaching of platinum method from secondary raw materials, in particular from ceramic support coated with platinum metal film. Target metals are leached with mixture of hydrochloric acid and alkali hypochlorite at mass ratio of OCl-/HCL = 0.22-0.25 and redox potential of 1350-1420 mV.
EFFECT: decreased leaching temperature, reduced cost, improved platinum metal yield.
FIELD: metal recovery, in particular noble metals from technologically proof raw materials.
SUBSTANCE: method includes raw grinding to 0.2 mm; blending with batch containing halogen salts and/or oxygen-containing salts, and mixture opening: cake cooling, leaching with simultaneous reaction pulp agitation with hot water, and metal recovery from solution and insoluble residue. Opening is carried out in electrical furnace at 100-120oC preferably at redox potential of 1.8-2.6 V, by elevating of temperature up to 450-560oC at rate of 8-10oC/min and holding for 1-7 h at highest mixture redox potential. Opened and cooled cake is grinded and leached in opened agitator.
EFFECT: environmentally friendly method with increased yield; utilization of unconventional noble and non-iron metal sources.
1 cl, 2 tbl
FIELD: non-ferrous metallurgy; leaching-out polymetallic hard-to-open materials.
SUBSTANCE: proposed method includes treatment of material with chlorine in aqueous solution containing chlorine ions which is stirred in anode space of electrolyzer with separated anode and cathode spaces; as a result pulp is obtained; leaching-out operation is performed in anode space of electrolyzer separated from cathode space by cation-exchange membranes; operation is performed in aqueous solution containing hydrochloric acid in presence of nitrogen oxides at additional delivery of chlorine-containing gas by suction of this gas into rarefaction zone formed by impeller stirring the pulp. Gas formed during leaching-out process is combined with chlorine-containing gas; layer of finely-dispersed particles formed on surface of pulp is removed and is fed to stirring zone in lower part of anode space; productive leaching-out solution obtained after separation of it from insoluble residue is delivered to cathode space of electrolyzer; leaching-out process is performed at anode potential ensuring discharge of chlorine ions and cathode potential not exceeding the potential of discharge of hydrogen ions. Device proposed for realization of this method has housing with cover; interior of housing is divided into anode and cathode spaces with anodes and cathodes located inside them, units for loading the initial materials and discharging pulp formed during leaching-out process and units for mixing and feeding the chlorine-containing gas; anode space is made in form of chamber and cathode chambers are located on its opposite sides; anode chamber walls contain cation-exchange membranes; stirring unit is provided with impeller located below lower edge of anodes; vertical fins are provided on inner surface of anode chamber at level of impeller.
EFFECT: increased rate of extraction of beneficial components from initial material into solution for further extraction of them from solution.
17 cl, 3 dwg, 1 tbl, 8 ex
FIELD: mining art; hydro-metallurgical processing of ores and concentrates; extraction of beneficial components by underground leaching, heap leaching, vessel leaching and tank leaching.
SUBSTANCE: proposed method includes preparation of material for leaching-out process, delivery of leaching solution, discharge, collection and reworking of productive solution; intensification of leaching-out process is performed through ultrasonic treatment of material which is preliminarily saturated with solution of reagent (or water)inert to beneficial component and dissolving harmful admixtures. After discharge of leaching solution (or water), beneficial component is leached-out by leaching solution till reduction of its concentration in productive solution corresponding to maximum level obtained during standard leaching-out process. Then periodic ultrasonic treatment of material is performed again at contact with leaching solution till concentration of beneficial component in productive solution gets equal to permissible level for reworking of this solution in settling plant. Periodicity of ultrasonic treatment is determined by special relationship; radiators are mounted in cylindrical cavities (wells) or on surface of material.
EFFECT: enhanced intensification and efficiency due to increased rate of extraction of beneficial components; reduced consumption of reagents.
5 cl, 3 dwg,1 ex
FIELD: metallurgy; production of platinum and palladium concentrates and silver from platinum-containing raw materials.
SUBSTANCE: proposed method includes sulphatizing roasting and/or sulphatizing of platinum-containing raw material at temperature of 200-600 C for 1-17 hours. Cinder is molten with sodium chloride at mass ratio of 1:(1-10) at temperature of 600-900 C; fusion cake is leached-out with water at mass ratio of fusion cake to water equal to 1: (1-10) at temperature of 80-90 C. After filtration of this pulp filtrate and residue are obtained; filtrate settles separating the silver concentrate in form of sediment of insoluble salt of silver chloride from liquid phase. Silver concentrate is washed with solution of concentrated hydrochloric acid and water at mass ratio of 1:10; leaching residue is washed with solution of concentrated hydrochloric acid and water at ratio 1:1, after which it is washed with water. Washing water is mixed with liquid phase obtained after separation of silver chloride from filtrate and sediment in form of platinum-palladium concentrate is let to settle; this sediment is separated by filtration and is washed with water.
EFFECT: complete primary extraction of platinum metals from platinum-containing raw material; reduced toxicity; reduced duration of process; reduced power requirements.
1 tbl, 1 ex
FIELD: sludge recovery from surface depositions of chemical equipment.
SUBSTANCE: invention relates to method for recovery of sludge containing platinum-group metals from equipment using platinum metal-based catalysts. Method includes treatment with aqueous solution of active chemical agent (e.g. sodium-ammonium-substituted ethylenediaminetetraacetic salts) while controlling pH value and removing sludge retained on treated surface with diluted aqueous solution of mineral salts or mixture thereof. pH value is adjusted at 2-10, preferably at 3-9 by adding of organic acid selected from group containing citric, oxalic, maleic, phthalic, adipic, glutaric, succinic acids or basic agents selected from sodium hydroxide, potassium hydroxide, sodium carbonate or potassium carbonate, and hydrochloric acid, sulfuric acid or phosphoric acid is used as mineral acid.
EFFECT: recovery platinum-group metal with improved yield.
4 cl, 1 tbl, 12 ex
FIELD: noble metal metallurgy, in particular method for gold content determination in natural solid organic materials such as divot, state coal, brown coal, and black coal.
SUBSTANCE: claimed method includes sampling the probe of starting material, grinding, mixing with massicot, smelting to form bullion, parting of gold-silver globule, weighting of gold sinterskin. Probe is sampled from starting natural solid organic material. Before smelting mixture is packaged in lead foil, established in full-hot scorifying dish, and padded with borax and table salt.
EFFECT: precise method for gold content determination in natural solid organic materials.
1 tbl, 1 ex
FIELD: precious metals technology.
SUBSTANCE: method comprises treatment of initial material with reagent solution under microwave irradiation to transfer precious metals into solution. Initial material is preliminarily subjected to mechanical activation during 5 to 120 min while maintaining ratio of mechanical power supplied to specific surface area of activated material within a range of 0.0133 to 25 W-kg·m2. Microwave treatment starts directly after mechanical activation using acid and/or oxidant to form slurry from activated material and reagent solution. Irradiation is carried out to boiling temperature. Acid and/or oxidant is selected from HCl and/or Cl2, HCl and/or H2O, HCl and/or Br2, HCl and/or NaClO3, HCl and/or HNO3, HF and HCl and/or NaClO3, mixtures of H2SO4 and HCl and/or H2O2, mixtures of HCl and HBr and/or H2O2, mixtures of HCl and HI and/or NaClO3 and J2, HCl and/or Cl2 and Br2.
EFFECT: increased degree of precious metal recovery.
3 cl, 13 ex
FIELD: waste water treatment and hydrometallurgy.
SUBSTANCE: invention relates to recovering palladium from nitric acid, nitric acid-hydrochloric acid, and nitric acid-fluoride-hydrochloric acid solutions used for etching parts and units of equipment for isotope separation chambers. Palladium is sorbed from solutions having nitric acid concentration 30 to 250 g/L with mixture of epoxypolyamine-type low-basicity anionite, containing alternating groups of secondary and tertiary amines, ethers, and alcohols, and high-basicity anionite with quaternary ammonium base groups, content of low-basicity anionite (e.g. AN-31) being 98-99% and that of high-basicity anionite (e.g. AV17*8) 1-2%. Thereafter, anionites are subjected to stepped combustion: first for 2-4 h at 350-400°C and then for 2-4 h at 950-1000°C to produce metallic palladium, which is cooled under vacuum or in an inert gas atmosphere.
EFFECT: increased selectivity of refining process removing polyvalent metal impurities and increased degree of recovery.
6 tbl, 5 ex
FIELD: waste treatment.
SUBSTANCE: multicomponent waste material is preliminarily impregnated with solution of salt of metal-collector in amount ensuring weight content of metal-collector in melt exceeding content of metallic components therein. Material is then calcined and melted in reductive atmosphere after addition of slag-forming flux based on metal fluorides. Melt is stirred and kept in liquid state over a period of time long enough to allow separation of slag and metallic phases. Resulting slag and metal are tapped and mechanically separated when solidified.
EFFECT: achieved high degree of recovering metals in collecting alloy at minimum expenses.