104 results about "Aqua regia" patented technology

The invention provides an agricultural soil heavy metal rapid detection method, and belongs to the technical field of heavy metal detection.The method comprises the steps that a sample is pretreated, a soil sample is air-dried and then ground, and the ground soil sample is sieved through a 100-mesh sieve; digesting graphite, weighing a sample, adding aqua regia, and digesting in a graphite digestion instrument; iCP-MS detection parameter optimization is carried out, and optimal working parameters of an instrument are determined; quantitative analysis is performed, and a standard curve is drawn; result analysis: calculating the content of heavy metal elements in the soil according to a calculation formula; high-flux detection of mercury and arsenic pollution is realized through combination of an integrated pretreatment process and an instrument, a corrosion-resistant centrifugal tube is taken as an integrated reaction container, a dynamic digestion system of a graphite digestion instrument is combined, and the addition amount and extraction time of aqua regia are optimized, so that the reagent consumption is remarkably reduced on the premise of ensuring full-amount extraction of a target object, and the detection efficiency is improved. Meanwhile, the pollution risk and element loss caused by sample transfer in a traditional method are eliminated.

The invention discloses a method for determining the content of phosphorus in activated carbon for wine, and relates to the field of detection of food processing assistants.The method comprises the steps that phosphorus standard solutions and phosphorus determination reagents are mixed to prepare phosphorus standard solutions with different concentrations, and phosphorus standard series working solutions are prepared; extracting phosphorus in the activated carbon by using aqua regia, preparing a to-be-detected solution by using the same method as the standard solution, and respectively determining absorbance of the phosphorus standard series working solution and the to-be-detected solution by using a spectrophotometer; and quantifying by adopting an external standard method, and calculating the phosphorus content in the activated carbon sample for filtering the wine. The method provided by the invention can realize accurate qualitative and quantitative analysis of the phosphorus content in the activated carbon for filtered liquor, effectively solves the problem that no standard method for detecting the phosphorus content in the activated carbon for filtered liquor exists in the liquor industry on the premise of meeting the analysis accuracy, and is simple and convenient, low in detection cost, good in repeatability of the analysis method and high in stability.

The invention discloses a rapid enrichment-atomic absorption spectrum analysis method for low-content gold in gold ore, and relates to the technical field of gold ore analysis and detection.The rapid enrichment-atomic absorption spectrum analysis method comprises the following steps that an ore sample and a solid composite additive are mixed and roasted at the low temperature of 500-650 DEG C, and the additive contains alkali metal carbonate and zinc oxide; sulfur fixation, catalytic oxidation of organic carbon and stabilization of volatile elements can be synchronously realized; the method comprises the following steps: roasting gold-loaded activated carbon, dissolving the gold-loaded activated carbon in aqua regia to obtain a to-be-enriched solution, enabling the solution to pass through an adsorption column filled with modified activated carbon, pretreating the activated carbon with a 1-10% ammonium citrate solution to improve the selective adsorption capacity of the activated carbon on gold chloride complex ions, ashing the gold-loaded activated carbon, dissolving residues, fixing the volume, and measuring by using an atomic absorption spectrometry. According to the rapid enrichment-atomic absorption spectrum analysis method for the low-content gold in the gold ore, through cooperation of low-temperature roasting of the composite additive and selective adsorption of the modified activated carbon, the decomposition efficiency and enrichment selectivity of the ore difficult to treat are improved.

The invention relates to the technical field of preparation of iridium trichloride, in particular to a preparation method of high-purity iridium trichloride. Methanol, normal propyl alcohol and the like are added into reaction liquid obtained after ammonium chloroiridate and aqua regia are mixed and dissolved to serve as organic additives for nitrate removal, nitrate reacts with nitrate in the solution to generate gas, and nitrate ions are removed from the solution. Meanwhile, the added organic additives are all alcohol substances which are easy to remove and are extremely easy to volatilize in the subsequent reaction heating process, so that impurities which are difficult to remove cannot be introduced into a reaction system while nitrate is effectively removed, and the purity of a final product can be improved. Organic reducing agents with weak reducibility, such as oxalic acid, citric acid, vitamin C and sulfur dioxide, are used for carrying out reduction reaction, so that iridium powder cannot be separated out in the process of reducing tetravalent iridium, and the purity of trivalent iridium can be ensured. The crystal form of the obtained high-purity iridium trichloride is a beta form, and the purity of the high-purity iridium trichloride is greater than 99.997%.

The invention discloses a non-aqua regia gold extraction agent and method for recovering precious metal from waste containing precious metal. The non-aqua regia gold extraction agent is composed of nitrate, metal chloride and weak acid, by precisely regulating and controlling the concentrations of nitrate, chloride ions and hydrogen ions in the non-aqua regia gold extraction agent, the precious metal in the waste containing the precious metal can be subjected to green, efficient and selective oxidation leaching under the normal temperature condition, the precious metal ions in the leaching solution are subjected to reduction operation, and therefore the recovery rate of the precious metal in the waste containing the precious metal is improved. And a pure noble metal product can be obtained. Compared with a traditional aqua regia method, the method has the advantages that strong acid reagents such as concentrated nitric acid and concentrated hydrochloric acid are not used, corrosion to equipment and operation risks are remarkably reduced, and secondary emission of harmful gas is avoided. The method has the remarkable advantages of being environmentally friendly, easy and convenient to operate, mild in reaction condition, low in equipment requirement, high in leaching rate and the like, is suitable for large-scale and industrial production, and has wide application prospects and commercial value in the field of precious metal recovery.

The invention discloses a method for simultaneously determining total barium and sulfur in barite by inductively coupled plasma emission spectrometry. In this method, the sample is decomposed by melting with sodium carbonate and sodium hydroxide. The molten slag is extracted with hot water, nitric acid and a chromium internal standard solution are added, the crucible and the beaker are washed with dilute hydrochloric acid, water is added and shaken well, heated to boiling gently on a hot plate and then taken off and shaken well. After cooling, it is determined on an inductively coupled plasma emission spectrometer. The method of the invention makes use of the characteristic that barium sulfate has a relatively large solubility in reverse aqua regia, enabling barium and sulfur to coexist stably, and then simultaneously determines total barium and sulfur by inductively coupled plasma emission spectrometry, which has the characteristics of high detection efficiency, high precision, simple operation and low cost, and solves the technical problems that when determining total barium and sulfur in barite by traditional methods, sulfur and barium are difficult to coexist in the solution, usually two different methods are required to complete the determination, and even barium and sulfur need to be separated in advance, resulting in a long process and low detection efficiency.

The invention relates to the technical field of detection, and particularly provides a method for determining the quality and purity of silver in a silver-gold-plated product. The determination method comprises the following steps: dissolving a surface gold plating layer of a silver-plated product with aqua regia, and then dissolving a silver chloride protective film on the surface of silver with ammonia water, so that the problem that the mass of silver cannot be accurately weighed after the gold plating layer in the product is removed is solved, and the problem that the silver chloride protective film hinders the dissolution of pure silver with nitric acid to influence the determination is also solved. Thiourea is further adopted to dissolve a complex of diamine and silver, the situation that when silver is dissolved, added nitric acid reacts with the complex of diamine and silver to generate silver chloride precipitates is prevented, an ammonium nitrate solution is used for washing thiourea, a flame atomic absorption spectrometry method is adopted for conducting mass correction on silver in the solution obtained after aqua regia gold is dissolved, and the total silver mass is obtained through calculation. According to the determination method, the quality and the purity of the silver in the silver-plated product can be relatively accurately obtained.

The application provides a method for preparing chloroplatinic acid based on waste platinum catalyst, comprising the following steps: pretreating the waste platinum catalyst to obtain crude metal platinum; dissolving the crude metal platinum in aqua regia to obtain a mixed solution; adjusting the pH of the mixed solution to 2.0-3.0, adding a first batch of reducing agent and dispersant, and reacting at 70-80 DEG C for 8-20 min to perform the first step reduction; adjusting the pH to 3.0-4.0, adding a second batch of reducing agent and dispersant, and continuing to react at 70-80 DEG C for 8-20 min to perform the second step reduction, so as to obtain a nano platinum system; separating to obtain monodisperse nano platinum; dissolving the monodisperse nano platinum in a hydrochloric acid-hydrogen peroxide system, the molar ratio of hydrochloric acid to hydrogen peroxide being 4:1-6:1, the dissolving temperature being 130-140 DEG C, and the dissolving time being 20-30 min, so as to obtain a chloroplatinic acid solution; and evaporating and crystallizing the chloroplatinic acid solution to obtain chloroplatinic acid crystals.

The invention discloses a method for preparing large-specific-gravity platinum powder from crude platinum, and belongs to the technical field of platinum group metal refining. According to the method, efficient purification of platinum and preparation of large-specific-gravity platinum powder are realized by adopting a combined precipitation method through the core steps of dissolving for liquid preparation, ammonium chloride precipitation, dissolving for impurity removal, acidification precipitation, reduction and the like. The method comprises the following specific steps: dissolving crude platinum with aqua regia to prepare a crude platinum solution, precipitating with ammonium chloride to generate ammonium chloroplatinate, dissolving with a special reagent to remove platinum group metal and base metal impurities, acidifying, precipitating, further purifying, and finally reducing with a liquid phase to obtain the large-specific-gravity platinum powder. The method is short in technological process, easy in process control, simple in operation equipment and suitable for large-scale production, the product purity is higher than 99.99% of sponge platinum requirements in the national standard GB / T-1419, the tap density is larger than 3.5 g / mL, and the method has wide application value in multiple fields of jewelry, chemical engineering, medicine, electronics, ceramics and the like.

The invention relates to the technical field of steel and iron material performance detection, in particular to a corrosion method for displaying the original austenite grain boundary of martensitic steel, a corrosion solution does not contain picric acid, a nitric acid alcohol solution and an aqua regia solution, the danger is low, raw materials are easy to obtain, the corrosion process is easy to operate, and the efficiency is high. The original austenite grain boundary of the martensitic steel can be clearly displayed without using electrochemical corrosion complex equipment; a mixed solution of hydrofluoric acid and hydrogen peroxide is selected as a corrosive agent for the austenite grain boundary of the martensitic steel, the corrosivity of the corrosive agent is just matched with the corrosion resistance of the grain boundary of the martensitic steel with medium and low carbon and the Cr content smaller than or equal to 15 wt%, the corrosive agent has sensitivity to the grain boundary, the grain boundary can be clearly displayed, the corrosive agent is not sensitive to an intragranular martensitic structure, and the good inhibition effect is achieved; therefore, a perfect austenite grain boundary display effect is obtained.

The invention provides a method and a device for microwave digestion of a geological sample under normal pressure, the method for microwave digestion of the geological sample under normal pressure comprises the following steps: S1, taking a first preset amount of geological sample, grinding until the granularity is less than 200 meshes, putting into a digestion bottle, and adding hydrofluoric acid with a first preset volume and nitric acid with a second preset volume; s2, standing for a first preset time for pre-digestion; s3, performing microwave digestion on the pre-digested geological sample for a second preset time until the geological sample is completely dissolved in a solution of hydrofluoric acid and nitric acid; s4, cooling the geological sample solution subjected to microwave digestion; s5, placing the cooled solution of the geological sample on a heating plate for heating, and performing acid removal on the solution of the geological sample at a first preset temperature until thick liquid drops appear at the bottom of the digestion bottle; s6, cooling to normal temperature, adding aqua regia, and fixing the volume to 100 ml; and S7, placing the sample in an inductively coupled plasma mass spectrometer to test trace elements in the geological sample.

The invention belongs to the technical field of recycling of rare and noble metal secondary resources, and discloses a method for preparing a tungsten compound and chloroplatinate from a waste catalyst and application of the method. The method comprises the following steps: (1) firing and crushing the waste catalyst, (2) reacting the waste catalyst with acid, (3) filtering and discarding filtrate, (4) reacting the precipitate with ammonia water, filtering to obtain an ammonium tungstate solution, and retaining filter residues; (5) concentrating the ammonium tungstate solution, crystallizing, separating and drying to obtain an ammonium paratungstate finished product; and (6) reacting the filter residues retained in the step (4) with aqua regia to prepare chloroplatinate. And (7) firing the ammonium paratungstate at a high temperature to obtain tungsten trioxide. According to the method, tungsten and platinum can be effectively separated from the carrier, and the recovery rate of rare and precious metals is increased.

The embodiment of the invention provides a method for preparing palladium nitrate at normal temperature and a preparation system thereof, and relates to the technical field of palladium nitrate preparation methods.The method comprises the steps that S1, aqua regia dissolution-oxidation is conducted to obtain an H2PdCl6 solution, S2, high-valence palladium liquid is subjected to ultrasonic reduction to obtain high-activity palladium powder, and S3, the high-activity palladium powder is obtained. The high-activity palladium powder obtained in the second step is filtered and washed, 0.50%-2% of pH maintaining agent is adopted for washing for 1-2 times, and then deionized water at the temperature of 40-50 DEG C is adopted for washing till the palladium powder is neutral; a certain amount of nitric acid is weighed according to the required concentration of palladium nitrate, then the high-activity palladium powder washed to be neutral in the step S3 is equally divided by weight, and sufficient nitric acid is sequentially and sufficiently stirred and dissolved in a segmented mode. According to the scheme, nitric acid does not need to be additionally added, and the obtained palladium nitrate is high in concentration.

A method for efficiently recovering iridium from organic coating liquids involves first mixing the coating liquid with an alkaline solution, stirring and reacting at room temperature, followed by solid-liquid separation. The solid is dried and dehydrated for later use, while the liquid is the supernatant. The supernatant is heated, and an alkaline solution is added and stirred to react. After sufficient settling, solid-liquid separation is performed again. The solid is dried and dehydrated, then ground together with the previously dried and dehydrated solid into powder. The powder is then calcined in a muffle furnace to obtain iridium and tantalum oxide powders. HF is added to the oxide powders to remove impurities such as Ta2O5, and solid-liquid separation is performed again. The solid is washed with water until neutral, dried and dehydrated, dissolved in aqua regia, and concentrated by heating to obtain chloroiridium acid. The method provided by this invention has a simple synthesis process, the supernatant after precipitation is free of iridium, the iridium loss rate is low, effectively reducing iridium loss in the organic liquid evaporation and concentration steps, and the HF removes tantalum, allowing direct dissolution of IrO2 in aqua regia, improving efficiency and reducing iridium loss during the process.

The invention relates to a sample pretreatment method for chromite microelement analysis. The method comprises the following steps: firstly, treating a sample to specific particle size distribution (Dv (50) lt, 5 [mu] m, Dv (90) lt, 20 [mu] m) through physical accurate grinding, and then adopting an improved two-step acid dissolution and digestion process: firstly, destroying main crystal lattices of minerals by using mixed acid, then, carrying out targeted dissolution on a residual insoluble phase by using aqua regia, and finally, carrying out chlorine removal treatment to obtain a solution to be detected. Through the synergistic effect of physical accurate grinding and secondary acid dissolution, almost complete decomposition of chromite is achieved, especially the extraction efficiency of key indissolvable elements such as Sc and Zn is improved by 20% or above, the accuracy and precision of ICP-MS analysis results are remarkably improved, and the problem that microelement measured value systematicness is low due to incomplete dissolution in a traditional method is solved.

The application provides a purification method of crude palladium, and belongs to the technical field of precious metal purification. In the application, the precious metals such as palladium in the crude palladium are dissolved by aqua regia, then the palladium ions are oxidized into high-valence palladium by an oxidizing agent, and then the high-valence palladium is precipitated into palladium salt by a precipitating agent, so as to improve the purity; then the palladium salt is dissolved by an inorganic solvent, so as to remove the impurities such as platinum, copper, iron and silver, thereby improving the purity of the palladium; the palladium ions in the filtrate are complexed by a first complexing agent, so as to obtain a sub-palladium salt precipitate, thereby removing the impurities and improving the purity of the palladium; then the palladium ions are further complexed by a second complexing agent, thereby further improving the purity of the palladium; and then electro-deposition is adopted, so as to ensure that the palladium ions are fully reduced into palladium powder, thereby improving the purity of the palladium. The experimental results show that the purity of the palladium powder obtained by the purification method is greater than or equal to 99.95%.

The invention belongs to the technical field of metallurgy, and particularly discloses a method for extracting gold from refractory iron-sulfur-gold concentrate by a wet process, which comprises the following steps: smelting the refractory iron-sulfur-gold concentrate by a pyrogenic process to obtain iron matte slag rich in gold and silver; the method comprises the following steps: crushing, ball-milling and slurrying the iron matte slag, introducing rich oxygen, carrying out pressure leaching under an acidic condition, and carrying out liquid-solid separation to obtain oxygen pressure leaching liquid and oxygen pressure leaching slag; cooling and crystallizing the oxygen pressure leachate to recover ferrous sulfate heptahydrate, and periodically vulcanizing, precipitating and recovering other valuable metals through crystallization mother liquor; sulfur, sulfur concentrate slag and gold and silver slag are separated from oxygen pressure leaching slag through conventional flotation, the sulfur concentrate slag is returned to the pyrogenic smelting process, and gold and silver products can be obtained by dissolving the gold and silver slag through aqua regia and selective reduction.

The invention relates to the technical field of isotope solution storage, in particular to an antimony isotope standard solution and a preparation method and application thereof.The method comprises the steps that antimony isotope particles are dissolved in a mixed solution of reverse aqua regia and hydrofluoric acid and dried, and an antimony isotope solid matter is obtained; reverse aqua regia and hydrofluoric acid are ingeniously selected as a dissolving system, Sb < 3 + > is complexed by hydrofluoric acid to form [SbF6] < 3->, the problem of isotope ratio drift caused by Sb < 3 + > hydrolysis is effectively inhibited, the strong oxidizing property of the reverse aqua regia ensures that Sb is completely converted into Sb < 5 + >, and the content of the Sb < 5 + > is increased. Therefore, valence fluctuation is avoided, long-term stable preservation of the antimony isotope standard solution is achieved, and the problems that an existing antimony isotope standard solution is prone to hydrolysis and unstable in valence are effectively solved.

The application provides a method for jointly measuring gold and silver in smelting fumes, which adopts a fire assaying method to enrich gold and silver in the sample, and a large part of silver in the obtained gold-silver combined particle is dissolved by using a nitric acid solution, after filtration, gold in the filter residue is dissolved by using aqua regia, after silver chloride is precipitated and separated from gold and silver again, the remaining small amount of silver in the filter residue is dissolved, the segmented digestion method prevents "passivation" of silver in the combined particle when the aqua regia directly dissolves the silver, and ensures that the gold and silver in the combined particle are completely dissolved into the solution, and then atomic absorption spectrometry is adopted to jointly measure the gold and silver, compared with the existing gold-silver separate measurement method of measuring gold by the fire assaying method and measuring silver by the atomic absorption spectrometry, the detection process is shortened and the detection efficiency is improved, and therefore the method has a certain application prospect.

The present application relates to a method for determining high content copper, lead and zinc in polymetallic ore and copper-lead-zinc alloy by ICP-AES, and belongs to the technical field of ICP-AES analysis and testing, and the specific steps are as follows: the polymetallic ore and copper-lead-zinc alloy sample is decomposed into wet salt by aqua regia; then hydrochloric acid-ammonium acetate mixed extraction liquid is added, and the mixture is heated to micro-boiling for 10-15 min; the extracted sample is diluted with deionized water in a 250 mL volumetric flask; the diluted sample is shaken and left to clarify; 5 mL of supernatant solution is taken out with a 10 mL large-volume pipette and placed in a 50 mL colorimetric tube, 5 mL of hydrochloric acid-ammonium acetate mixed extraction liquid is added, and the mixture is diluted and shaken; the obtained sample is subjected to ICP-AES testing to determine the content of copper, lead and zinc. The present application avoids complicated operation, solves the problem of serious low test results caused by mutual influence of lead, copper and zinc during testing, and can improve the testing accuracy of high content copper, lead and zinc in polymetallic ore and copper-lead-zinc alloy.

The invention discloses a method for recovering ruthenium and iridium in a noble metal material based on a low-temperature plasma technology, and particularly relates to the field of noble metal recovery. The method comprises the following specific steps: putting a ruthenium and iridium-containing noble metal material into a low-temperature plasma reduction device, and carrying out low-temperature plasma treatment on the noble metal material by using a certain power in a chlorine atmosphere under a fixed low-pressure condition, converting a noble metal simple substance or a noble metal oxide which is difficult to dissolve in the aqua regia into a chloride which is easy to dissolve in the aqua regia, and finally carrying out various tests on the content of the noble metal in the filtrate. A novel precious metal material recovery technology is adopted, so that the precious metal can be dissolved in aqua regia more easily, and the purpose of improving the precious metal recovery efficiency is achieved. In the whole pretreatment process, the pollution to the environment is relatively small, and the energy consumption is relatively small; and the content of noble metals ruthenium and iridium which can be finally dissolved in aqua regia is relatively high, so that the method has more excellent economic benefits.

The invention relates to a method for measuring heavy metals in an electroforming solution, and particularly discloses a method for measuring the concentration of gold in a gold electroforming solution. The method comprises the following steps: 1) putting a gold electroforming solution into a beaker, adding acid (such as perchloric acid and nitric acid), heating to form a wet salt-shaped mixture, taking down and cooling, sequentially adding water, hydrochloric acid and aqua regia, and heating until the wet salt-shaped mixture is completely dissolved to form a solution to be detected; 2) drawing a standard curve on a machine by using a 1000 mg / L gold standard solution; (3) accurately transferring quantitative pretreated to-be-detected solution into a beaker, adding aqua regia, heating and dissolving on an electric heating plate, taking down and cooling, transferring into a volumetric flask, diluting with water to a set scale, and uniformly mixing to form a to-be-detected solution; 4, the solution to be measured is placed in a volumetric flask and diluted to the set scale of a beaker with water, dilution is conducted after even mixing, measurement is conducted on a machine, and finally the gold concentration in the gold electroforming solution is obtained.The method has the advantages that operation is easy and rapid, and the gold concentration can be accurately detected.

The invention relates to the technical field of high-purity noble metal catalysts, in particular to a preparation method of high-purity iridium powder, which comprises the following steps: iridium dissolution and liquid preparation: adding chloroiridic acid into deionized water, stirring and dissolving, and filtering to remove insoluble substances to obtain an iridium solution A; complexing and precipitating iridium: adding didecyl dimethyl ammonium chloride into the iridium solution A, heating to 80-90 DEG C, separating out a large amount of yellow precipitate, and filtering when the solution becomes colorless from orange red to obtain iridium-containing precipitate B; recrystallization: adding the iridium-containing precipitate B into deionized water for recrystallization, and filtering to obtain an iridium-containing precipitate C; dissolving the iridium-containing precipitate C to prepare a solution, namely adding the iridium-containing precipitate C into dilute ammonia water with the pH value of 8-9 to be dissolved to obtain an iridium solution D, and filtering to remove trace insoluble impurities; and reducing to obtain high-purity iridium powder: adding hydrazine hydrate into the iridium solution D under a micro-boiling condition for reaction, filtering after reduction to obtain iridium powder, boiling and washing with aqua regia, filtering, washing with deionized water, and drying in vacuum to obtain the high-purity iridium powder.

The application belongs to the technical field of wet assay, and provides a multi-module cooperative wet assay acid-dissolution automation device and method. The wet assay acid-dissolution automation device integrates a positive aqua regia real-time preparation pump group, a negative aqua regia real-time preparation pump group, a drop horizontal movement module and a cover opening module. The aqua regia real-time preparation, automatic cover opening, quantitative liquid addition and dynamic shaking are integrated in a single device, thereby solving the process fragmentation and cooperation failure caused by the traditional manual + multiple single machine mode.

This invention discloses a method for recovering gold from gold-containing materials using ultrasound-assisted persulfate extraction, belonging to the field of hydrometallurgical technology. The method involves mixing finely ground gold-containing materials, an acetonitrile aqueous solution, and persulfate, followed by ultrasound-enhanced leaching in an alkaline environment. After leaching, solid-liquid separation is performed to obtain a leachate and a leaching residue. The leachate is then evaporated and crystallized to achieve solvent recovery and reuse, as well as separation of the gold-containing solids. The gold-containing solids are then reduced and calcined to obtain elemental gold. Compared to traditional cyanide and aqua regia leaching processes, this invention eliminates the need for toxic substances and catalysts, significantly improving the selective extraction efficiency of precious metals through ultrasound enhancement. Simultaneously, the solvent can be recycled, reducing costs and avoiding excessive waste residue. This method is green, safe, and highly efficient, possessing significant potential for industrial applications.

The invention provides a method for simultaneously detecting gold and silver in smelting smoke dust, which comprises the following steps of: enriching gold and silver in a sample by adopting a fire assaying method, dissolving most of silver in obtained gold-silver particles by using a nitric acid solution, filtering, dissolving gold in filter residues by using aqua regia, filtering silver chloride again, precipitating and separating the gold and the silver, and detecting the content of the silver in the gold-silver particles. According to the sectional digestion mode, the situation that the silver in the combined particles is directly dissolved by the aqua regia to cause passivation is prevented, it is guaranteed that the gold and the silver in the combined particles are completely dissolved into the solution, and then the gold and the silver are jointly measured through the atomic absorption spectrometry. Compared with an existing gold and silver separate detection mode for detecting gold through a fire assaying method and silver through an atomic absorption spectrometry method, the detection process is shortened, the detection efficiency is improved, and therefore the method has a certain application prospect.

The invention relates to the technical field of ionizing radiation and gold extraction, in particular to a method for selectively dissolving gold from gold ore through ionizing radiation. The method comprises the following steps: immersing a gold ore material to be extracted into a solution of an organic nitrile compound, carrying out radiolysis reaction under high-energy ray irradiation, and selectively dissolving gold in the gold ore. The method disclosed by the invention has the advantages of mildness, energy conservation, greenness, high efficiency, environmental protection and low cost, does not need to use strong corrosive aqua regia and highly toxic cyanide, and does not need other additional catalysts and oxidants. And meanwhile, base metals (such as iron, copper, zinc, nickel and the like) are not dissolved.

The invention discloses a sponge platinum preparation method and sponge platinum prepared by the same, belongs to the technical field of precious metal material preparation, and aims to solve the problems that existing sponge platinum is insufficient in purity, poor in morphology and granularity controllability, low in efficiency and insufficient in thermal stability, the purity of a raw material chloroplatinic acid is difficult to control, and safety and environmental protection are poor. The chloroplatinic acid is prepared by dissolving platinum powder and aqua regia at the temperature of 80-90 DEG C, evaporating and concentrating, refrigerating and crystallizing, and drying at the low temperature of 40-60 DEG C; the preparation method comprises the following steps: by taking chloroplatinic acid as a raw material, preparing a solution, stirring at 60-80 DEG C at 200-250r / min, adjusting the pH to 8-10 at a sodium hydroxide dropping rate of 1-3mL / min, adding formaldehyde to carry out reduction reaction, carrying out centrifugal separation at 1000-2000r / min, washing until no chloride ions exist, and drying at 100-120 DEG C for 0.5-1h to obtain the sponge platinum. Full-process parameters are optimized, the total impurity content of the prepared sponge platinum is smaller than or equal to 0.0005%, the sponge platinum is in a uniform porous spherical shape, the average particle size is 1-5 microns, the mass loss at the high temperature of 400 DEG C is smaller than or equal to 0.1%, the total reaction time is smaller than or equal to 2 h, the platinum recovery rate is larger than or equal to 99.5%, and the sponge platinum is safe and environmentally friendly and can meet the requirements of the fields of high-end electrons, precise catalysis and the like.

The invention discloses a continuous detection method for the content of copper, lead and zinc in gold mud, and belongs to the technical field of chemical analysis and detection. The method comprises the following steps: dissolving a gold mud sample in aqua regia at low temperature, forming an AgCl precipitate in a certain acidic environment to remove silver ions, reducing gold with sodium sulfite, adding sodium bromide and tartaric acid to mask interference, dispersing colloid, performing hot filtration separation, recovering gold and silver, and determining the content of copper, lead and zinc in a constant volume of filtrate. Tartaric acid and NaBr have a good synergistic effect, form double complexation, are suitable for high-content lead samples, mask metal ion interference, disperse colloid and reduce physical adsorption of precipitates, are high in applicability and low in consumption for gold mud samples with complex matrixes, and can ensure that the contents of copper, lead and zinc can be rapidly and accurately measured in metallurgical production.

The invention relates to a method for determining the platinum content in platinum-tungsten alloy slag. The invention aims to solve the problems of incomplete digestion, platinum loss, matrix interference and the like when the high-tungsten low-platinum alloy slag is treated by the existing wet digestion technology. The method is based on a fire assaying enrichment principle, and comprises the following steps: mixing and melting a sample, lead powder and pure gold with known mass, carrying out soot blowing to obtain platinum alloy particles, dissolving the platinum alloy particles through aqua regia, determining the total amount of impurities in combination with ICP (Inductively Coupled Plasma) spectrum, and finally calculating the platinum content according to Pt (%) = (W2-W1-W3) / W0 * 100%. According to the method, efficient separation of platinum and tungsten is effectively achieved, the determination accuracy and reproducibility are remarkably improved, and the method is suitable for rapid, safe and high-precision analysis of various platinum-tungsten alloy slag.