34 results about "Silver sulfate" patented technology

The utility model belongs to the technical field of reaction kettle cleaning, and particularly relates to a cleaning device for a vertical silver sulfate reaction kettle, which comprises a rotating shaft arranged in the reaction kettle, hollow inside and filled with cleaning water; a driving mechanism is arranged at the top end of the rotating shaft, so that the rotating shaft is driven to rotate when the driving mechanism is started; the cleaning mechanism is arranged on the outer wall of the hollow rotating shaft and is suitable for spraying cleaning water towards the inner wall of the reaction kettle through a water outlet end on the cleaning mechanism when the rotating shaft rotates; the auxiliary mechanism is in sliding connection with the cleaning mechanism and is suitable for sliding relative to the cleaning mechanism to press the water outlet end of the cleaning mechanism when the rotating speed of the rotating shaft is increased, so that the flow speed of the cleaning water is increased, and the inner wall of the reaction kettle is cleaned.

The present invention provides a method for preparing silver-coated copper powder, which relates to the technical field of metal powder preparation. This preparation method directly prepares a copper core by chemical reduction method, then uses electroless plating method to grow a silver layer on its surface, and finally uses jet milling to improve the density of the powder. In the present invention, reducing agents with different reduction effects are added twice to reduce copper sulfate, which reduces the initial reaction rate, makes the whole reaction stable, and improves the sphericity of copper crystal nuclei. At the same time, sulfate radicals in the reaction system can form silver sulfate precipitation with silver ions in the subsequent reaction, further slowing down the reduction rate of silver ammonia complex ions and enabling the dense growth of the silver layer. At the same time, the unreacted completely glucose remaining in the reaction system can continue to reduce silver ammonia complex ions when silver ammonia solution is added dropwise later. By strictly controlling the growth rate of silver powder from crystal seeds to particles, the present invention reduces the structural defects caused by rapid growth and improves the performance of the final product.

The invention provides a preparation method of silver-coated copper powder, and relates to the technical field of metal powder preparation. According to the preparation method, a copper core is directly prepared by adopting a chemical reduction method, then a silver layer is grown on the surface of the copper core by adopting a chemical plating method, and finally, the powder compactness is improved by adopting a jet mill polishing mode. The reducing agents with different reducing effects are added twice to reduce copper sulfate, so that the initial reaction rate is reduced, the whole reaction is stable, and the sphericity degree of copper crystal nucleus is improved; meanwhile, sulfate radicals in the reaction system and silver ions in the subsequent reaction can form silver sulfate precipitates, the reduction speed of silver-ammonia complex ions is further reduced, and the silver layer grows compactly; and meanwhile, the incompletely reacted glucose remained in the reaction system can be used for continuously reducing silver-ammonia complex ions when the silver-ammonia solution is subsequently dropwise added. By strictly controlling the growth speed of the silver powder from the seed crystal to the particles, the structure defects caused by rapid growth are reduced, and the performance of the final product is improved.

The invention discloses a method for recovering valuable metals from copper anode slime step by step, and belongs to the technical field of metallurgy and chemical industry. According to the method, through control over the oxidation-reduction potential, the oxidation-reduction potential is high in the leaching stage, and it is guaranteed that gold, selenium, tellurium and the like can be oxidized to enter a leaching solution; in the reduction stage, gold, selenium and tellurium products are reduced step by step according to the difference of gold, selenium and tellurium in reduction potentials; in the leaching stage, soluble chlorine salt is added while enough oxidation potential is guaranteed, enough chloride ions are provided for the solution, and therefore gold can enter the solution in the form of AuCl4-(tetrachloroauric acid); meanwhile, in the oxidation leaching stage, a small amount of silver enters the solution in the form of silver sulfate or silver complex, and under the condition that enough chloride ions are provided, silver is precipitated and retained in residues in the form of silver chloride, so that separation of gold and silver is achieved, and meanwhile dispersion of gold and silver in the leaching process is reduced. According to the method, valuable metal is efficiently separated and recycled.

The invention provides a reflective integrated electrochromic device. The reflective integrated electrochromic device sequentially comprises a first substrate layer, a working electrode layer, an integrated electrochromic layer, a counter electrode layer and a second substrate layer, the integrated electrochromic layer comprises a metal source compound; the metal source compound is selected from silver chloride, silver acetate, silver nitrate, silver perchlorate, silver sulfate, silver cyanide, silver sulfide, silver hexafluorophosphate, silver tetrafluoroborate, silver tetrachloroaluminate, silver trifluoromethanesulfonate, silver bis (trifluoromethane sulfonimide), copper fluoride, copper chloride, copper cyanide, copper sulfate, copper acetate, copper aluminate, cuprous fluoride, cuprous chloride, cuprous cyanide, gold chloride and gold cyanide; the catalyst is one or more of gold sulfide, gold chloride, gold (II) sulfide, nickel chloride, nickel sulfate, cobalt chloride and platinum chloride. The device has a relatively large transmittance / reflectivity dynamic change range, can perform light and heat management at the same time, and can keep a stable coloring or fading state for one month or even several months under a no-load condition.

The invention relates to a vase solution for preserving cut lily flowers of an OT hybrid line and application of the vase solution. The vase solution takes water as a solvent and comprises salicylic acid, citric acid, calcium chloride, 6-benayl aminopurine, aspirin, ascorbic acid, silver thiosulfate and cane sugar. The vase solution can improve the ornamental quality of cut flowers, remarkably prolong the service life of flowering branches and delay turbidity of the vase solution; in addition, the soluble sugar content and peroxidase content of the petals can be increased, and the malondialdehyde content of the petals can be reduced. The vase solution provided by the invention has the advantages of low cost, and simple and easy preparation and use.

The invention discloses an acarus killing composition as well as a preparation method and application thereof, and relates to the technical field of pet supplies. The invention provides an acarus killing composition. The acarus killing composition comprises the following components in parts by weight: 0.3-1 part of a component A, 0.3-2 parts of a component B and 0.3-0.7 part of a component C, the component A comprises silver sulfate and silver; the component B comprises an ammopiptanthus mongolicus extract and a citronella extract; and the component C comprises dichlorobenzyl alcohol. Through a composite system of silver sulfate and silver, synergism of the ammopiptanthus mongolicus extract and the citronella extract and precise compounding of dichlorobenzyl alcohol, multi-mechanism synergistic acarus killing is achieved.

The present application relates to the field of metal particle preparation, in particular to a preparation method of silver crystal powder and application thereof. The present application provides a preparation method of silver crystal powder, which comprises adding silver sulfate and a reducing agent into an acid solution of a protective agent, and performing a reduction reaction under heating and stirring to obtain silver crystal powder. The present application provides a silver crystal powder, wherein the intensity ratio I (111) / I (200) of the silver crystal in (111) and (200) directions is greater than 4. The present application also provides a silver paste and a preparation method of the silver paste. The silver crystal powder provided by the present application has excellent shrinkage and crystallization properties, and the silver paste prepared by using the silver crystal powder has excellent high-temperature resistance and conductivity, and has a good prospect in application of electrode paste on the surface of electronic device electrodes.

The present invention discloses a method for preparing a solution of dinitrosoplatinous sulfate, which method comprises: 1) slowly adding an ammonium salt to an aqueous solution of potassium hexanitritoplatinate, stirring and heating for reaction to obtain a suspension containing ammonium hexanitritoplatinate precipitate, cooling, filtering, and washing with a cold ammonium salt solution to obtain a white solid of ammonium hexanitritoplatinate; 2) mixing the solid of ammonium hexanitritoplatinate with a dilute sulfuric acid solution, stirring and heating for reaction until no brownish-red gas is generated to obtain a solution of tetranitrosoplatinic sulfate; 3) after cooling the solution to room temperature, adding a reducing agent dropwise, stirring, and reacting until no more bubbles are generated to obtain a solution of dinitrosoplatinous sulfate. The present invention solves the problems of the addition of current dechlorination reagents such as silver sulfate, incomplete chlorine removal and additional introduction of silver ions. The whole technological process is simple, the overall cost is low, the economy is high, and it is suitable for industrial production.

The invention relates to the field of metal particle preparation, in particular to a preparation method and application of silver crystal powder. The invention provides a preparation method of silver crystal powder, which comprises the following steps: adding silver sulfate and a reducing agent into an acid solution of a protective agent, and carrying out reduction reaction under heating and stirring conditions to obtain the silver crystal powder. The invention provides silver crystal powder. The strength ratio I (111) / I (200) of silver crystals in the directions of (111) and (200) is larger than 4. The invention further provides the silver paste and a preparation method of the silver paste. The silver crystal powder provided by the invention has excellent shrinkage performance and crystallization performance, silver paste prepared from the silver crystal powder has excellent high temperature resistance and conductivity, and the silver crystal powder has a good prospect when applied to electrode paste on the electrode surface of an electronic device.

The invention relates to a hair dyeing composition and a preparation method thereof, the hair dyeing composition comprises a color developing agent and a hair dyeing agent, the hair dyeing agent comprises Tris and silver sulfate, and the color developing agent comprises sodium erythorbate or ferrous lactate. Tris is used as a dissolution promoting substance, so that the safety, the stability and the dyeing effect are remarkably improved.

The invention discloses a method for quickly testing chemical oxygen demand, which comprises the following steps of: 1, preparing a test solution which comprises the following components: A, a potassium dichromate solution (c is equal to 0.0250 mol / L); b, a mercury sulfate solution (100g / L); c, a silver sulfate-sulfuric acid solution (10g / L); 2, preparing a standard water sample; step 3, preparing a comparison reference sample, sequentially adding the standard water sample, the reagent B and the reagent A into the colorimetric tube, uniformly shaking, adding the reagent C into the colorimetric tube by using a pipette, uniformly shaking, and standing until the reaction is finished; 4, developing the water sample to be detected, sequentially adding the water sample to be detected, the reagent B and the reagent A into the colorimetric tube, uniformly shaking, adding the reagent C into the colorimetric tube by using the pipette, uniformly shaking, and standing until the reaction is finished; and 5, carrying out color comparison on the to-be-detected water sample obtained in the step 4 and a comparison reference sample.

The application discloses a silver sulfate silver ion slow-release compound, a preparation method and application thereof, and belongs to the field of chemical materials and slow-release technology. The preparation method of the silver sulfate silver ion slow-release compound selects modified porous materials as a slow-release carrier, precisely loads silver sulfate through impregnation or co-precipitation, constructs a gradient density regulation layer by using a high molecular polymer, and can introduce an environmental response additive to dynamically adjust the silver ion release rate. The application solves the problems that the silver ion release of the existing silver sulfate solution is too fast, the concentration fluctuation is large, and the silver ion release cannot adapt to complex scene requirements, has the characteristics of strong release controllability, wide adaptation range and low cost, and is suitable for various fields such as medical antibiosis and water purification.

The invention discloses an acidic corrosive liquid, which is used for revealing the ductility defect of cadmium telluride / cadmium zinc telluride. Comprising one of hydrofluoric acid, nitric acid, deionized water, lactic acid, silver nitrate or silver sulfate, and the volume ratio of the hydrofluoric acid to the nitric acid to the deionized water to the lactic acid is as follows: 10% of the hydrofluoric acid, 35% of the nitric acid, 25%-35% of the deionized water and 20%-30% of the lactic acid; one of the silver nitrate and the silver sulfate is used according to a set proportion. According to the acidic corrosive liquid and the preparation method thereof provided by the invention, a clean corroded crystal surface and clear defective corrosion pits can be obtained by using the acidic corrosive liquid, and the acidic corrosive liquid is simple to prepare, short in time consumption and good in practicability.

The invention discloses a preparation process and application of a lipid hydrocolloid silver sulfate acetate fiber dressing, and the preparation process comprises the following steps: sequentially adding thermoplastic rubber, liquid paraffin, tackifying resin, an antioxidant and a plasticizer into a kneading machine, stirring and mixing, then adding sodium carboxymethyl cellulose and silver sulfate, continuously stirring to uniformly mix, and thus obtaining the lipid hydrocolloid silver sulfate acetate fiber dressing. The preparation method comprises the following steps: preparing a hollow reticular cellulose acetate fiber spunlace non-woven fabric, adding medical vaseline, simethicone, liquid paraffin and citric acid to obtain a mixture, uniformly coating the hollow reticular cellulose acetate fiber spunlace non-woven fabric with the obtained mixture by adopting an extruder, cutting the hollow reticular cellulose acetate fiber spunlace non-woven fabric into a required shape, packaging, and carrying out radiation crosslinking to obtain the lipid hydrocolloid silver sulfate cellulose acetate fiber dressing. When the prepared dressing is used, a healing microenvironment with certain humidity and an antibacterial effect is provided, and the dressing is not adhered to the surface of a wound and peripheral skin, so that the dressing is free of pain and bleeding when being replaced, is particularly soft and easy to curl, and has relatively good compliance to the wound which is difficult to fix, and the antibacterial property of the dressing is further improved.

The invention relates to a method for rapidly determining the amino acid content of a copper-containing plating solution, which comprises the following steps: respectively preparing a potassium dichromate-sulfuric acid-silver sulfate mixed solution and a potassium dichromate-sulfuric acid mixed solution, and respectively sampling in a digestion colorimetric tube as a reagent tube A and a reagent tube B; establishing an amino acid standard curve; the method comprises the following steps: taking a to-be-detected solution of a copper-containing plating solution, putting the to-be-detected solution into a reagent tube A for digestion, and after digestion is finished, reducing the temperature to room temperature to obtain a sample A; taking the other part of to-be-detected copper-containing plating solution, putting the to-be-detected copper-containing plating solution into a reagent tube B, and washing and cooling the wall of the reagent tube to obtain a sample B; and determining the absorbance of the sample A by taking the sample B as a determination zero point according to the amino acid standard determination curve to obtain the amino acid content in the sample A. According to the method, pretreatment is not needed, direct determination can be achieved, and compared with a traditional determination method in which pretreatment is needed for eliminating metal ion interference and then determination is conducted, the steps are simple, the determination range is wide, and good application prospects are achieved.

The invention relates to the technical field of preservation of picked fresh cut flowers, and discloses delphinium grandiflorum cut flower pre-treatment liquid as well as a preparation method and application thereof. The pre-treatment liquid is prepared from the following components in percentage by mass / volume: 200 to 300 mg / L of 8-hydroxyquinoline, 250 to 450 mg / L of citric acid, 25 to 45 mg / L of silver nitrate, 400 to 800 mg / L of aluminum sulfate, 25 to 45 mg / L of silver thiosulfate and 1.5 to 3.0 mg / L of 1-MCP; the concentration of the Tween-20 is 0.4%-0.8% by volume, the problems that petals of delphinium grandiflorum cut flowers fall off, flower color fades, stalks are bent and the like due to ethylene sensitivity and catheter blockage are solved through the synergistic effect of the multiple components, the bottle insertion time is prolonged to 24-28 days, and the yield of the delphinium grandiflorum cut flowers is improved. The invention further provides an efficient and stable pretreatment liquid preparation process for ensuring the stability and permeability of components and a simplified pretreatment method, and is suitable for fresh cut flower manufacturers, logistics enterprises and terminal retailers. The contradiction between high toxicity of AgNO3 (reduced by 35% compared with that of an early-stage formula) and low stability of STS in a traditional formula is solved. The invention further provides an efficient and stable pretreatment liquid preparation process for ensuring the stability and the permeability of the components, and the pretreatment method is suitable for fresh cut flower manufacturers, logistics enterprises and terminal retailers.

The method comprises the following steps: weighing a certain amount of soil samples, putting the soil samples into a triangular flask, adding an ethylenediamine tetraacetic acid disodium salt solution with specific concentration and volume, a potassium dichromate solution and concentrated sulfuric acid containing silver sulfate, uniformly shaking, standing and oxidizing in a heat preservation environment, and carrying out gradient elution to obtain the easily oxidized organic carbon in the soil. Then adding sodium diphenylaminesulfonate and a ferrous sulfate solution for titration, and determining the easily oxidized organic carbon after titration is completed. According to the method, the detection efficiency and accuracy are remarkably improved through operations such as complexing of ethylenediamine tetraacetic acid disodium salt with metal ions, catalytic oxidation of silver ions, accurate indication of an end point by an indicator, optimization of the concentration of an oxidizing agent, the use amount of sulfuric acid and oxidation time, and the like, and many problems existing in a traditional potassium permanganate oxidation method are effectively solved. Compared with a traditional method, the method has the advantages of being easy and convenient to operate, high in detection efficiency, accurate and stable in result and the like, the requirement for measuring the soil easily-oxidized organic carbon in batches can be better met, and powerful support is provided for soil quality evaluation and related carbon research.

The utility model relates to the technical field of water quality analysis, and discloses a COD (Chemical Oxygen Demand) water quality analyzer, which is characterized in that a liquid discharge pipe is arranged at the lower part of a bottom plate, the liquid discharge pipe is connected with a detection pipe and a blow-off pipe in parallel, an adjusting valve and a COD detector are arranged on the detection pipe, a stop valve is arranged on the blow-off pipe, a feeding pipe is arranged on a cover plate, a flushing water pipe is arranged on the upper side of a barrel, and the flushing water pipe tangentially enters the barrel; the device disclosed by the utility model has the beneficial effects that the frequency converter controls the rotating speed of the speed reducing motor to change at any time, and the stirring paddle with the inconstant rotating speed avoids the laminar flow phenomenon when sewage and silver sulfate are mixed, so that the removal rate of chloride ions is improved, the COD (Chemical Oxygen Demand) detection is more accurate, and the production efficiency is improved. Meanwhile, the COD detector and the reaction tank can be flushed after detection is finished, so that the influence of residues on next detection is avoided.

The invention discloses a method for reducing silver powder production wastewater treatment difficulty by using silver sulfate as a precursor. The method comprises the following steps: dissolving silver sulfate in ammonia water to form a silver-ammonia complex solution, adding a reducing agent, reacting, filtering to obtain a solid and a reaction tail liquid, washing the solid until the conductivity is less than 25 [mu] s / cm, drying, crushing and screening to obtain superfine silver powder; adding calcium oxide into the obtained reduction tail liquid, filtering after reaction to obtain calcium sulfate precipitate and ammonia-rich reduction tail liquid, adding an aerator into the ammonia-rich reduction tail liquid, introducing compressed air for aeration treatment, absorbing volatilized ammonia gas by using a serial absorption device, and recycling the obtained ammonia gas to dissolve silver sulfate. Silver sulfate is used as a silver precursor, and the growth of a silver crystal face is regulated and controlled through the directional adsorption effect of sulfate ions; and the reduction tail liquid is subjected to calcium oxide precipitation-aeration treatment-series adsorption, so that ammonia resources are recycled.

The utility model discloses a chlorine-containing waste sulfuric acid recovery treatment device which comprises a treatment box, the side wall of the treatment box is vertically and fixedly connected with a connecting seat, the connecting seat is vertically and fixedly connected with an electric telescopic rod, the bottom end of the electric telescopic rod is fixedly connected with a fixing plate, and the upper surface of the fixing plate is detachably provided with a collecting barrel. And the side wall of the collecting barrel is fixedly connected with a sealing element which is propped against the inner wall surface of the treatment box. The utility model relates to the technical field of waste sulfuric acid recovery. According to the chlorine-containing waste sulfuric acid recovery treatment device, silver sulfate in the collecting barrel is stirred, follow-up discharging is facilitated, after silver sulfate is generated, an electric telescopic rod can extend to drive a fixing plate to descend, the collecting barrel is moved to the outside of the treatment box, workers can detach the collecting barrel, and the labor intensity of workers is relieved. And the silver sulfate collected in the collecting barrel is discharged, the discharging operation is simple and rapid, and the discharging efficiency of the silver sulfate in the device is improved.

The invention belongs to the technical field of fresh cut flower preservation, and discloses babysbreath cut flower forcing liquid and a preparation method thereof. The catalytic liquid is prepared from, by mass, 0.6%-1.6% of 8-hydroxyquinoline, 1.0%-1.8% of citric acid, 80-150 mg / L of gibberellin, 0.4%-1.2% of ascorbic acid, 60-100 mg / L of silver thiosulfate and 0.4%-1.5% of aluminum sulfate. The concentration of Tween-20 is 0.2%-0.5% by volume percent, so that the synchronization of rapid blooming of lower-layer flower buds and anti-aging of upper-layer flowers of the babysbreath cut flowers is realized, the blooming time of the lower-layer flower buds is shortened, and the qualification rate of commodities and the vase life are remarkably improved. The method is suitable for the whole process of grading, pretreatment, transportation and bottle insertion after harvesting of the cut babysbreath flowers. The invention further provides an efficient and stable flower forcing liquid preparation process, component stability and permeability are guaranteed, working efficiency and unit area stubbles and yield are improved so as to adapt to market changes, and the flower forcing liquid has good development prospects in production, popularization and application of babysbreath cut flowers.

A quaternary ammonium group-grafted cation resin and a preparation method thereof are provided. The preparation method includes: adding a chloromethylated cross-linked polystyrene (PS) resin, trimethylamine hydrochloride, and a 20% sodium hydroxide aqueous solution successively to a reactor for a reaction under stirring at 30° C. to 40° C.; filtering a resulting reaction solution, followed by washing and drying to obtain a quaternary ammonium group-grafted resin; adding the quaternary ammonium group-grafted resin, 1,2-dichloroethane, silver sulfate, concentrated sulfuric acid, and fuming sulfuric acid successively for a reaction for 1 hour at 50° C. to 60° C., a reaction for 1 hour at 70° C. to 80° C., and a reaction for 5 hours at 115° C. to 125° C.; and cooling a resulting reaction solution to room temperature, followed by diluting, filtering, washing and drying to obtain the quaternary ammonium group-grafted cation resin.

The invention discloses a silver electrolysis purification residue treatment method, and relates to the technical field of non-ferrous metal smelting waste treatment. The method comprises the working procedures of presoaking treatment, pressure leaching, two times of solid-liquid separation and subsequent resource recovery, wherein during presoaking, process water, anode mud, concentrated sulfuric acid, silver electrolysis purification residues and urea are added into a presoaking kettle according to the proportion, and leaching is conducted for 2-3 h while stirring is conducted at the temperature of 80-90 DEG C; putting the pre-impregnated material into a high-pressure kettle, firstly carrying out anaerobic leaching for 0-2 hours, and then introducing oxygen to carry out pressure leaching for 4-8 hours under the conditions that the temperature is 120-130 DEG C and the pressure is 0.4-0.68 Mpa; the pressurized slag is pulpified and washed and then enters an alloying furnace to be blown into a silver anode plate, the silver anode plate is sent to a silver electrolysis process, the pressurized liquid enters a normal pressure kettle, iron powder is added at the temperature of 70-80 DEG C to react for 1 h, copper powder is added at the temperature of 80-90 DEG C to react for 4-6 h, after cooling and filter pressing, filter residues are sent to tellurium for refining, and filtrate is sent to copper salt for extraction. According to the method disclosed by the invention, the processes of presoaking, pressure leaching and normal-pressure leaching are cooperated, and harmless gas is generated through nitrate radical reaction during presoaking, so that the environmental protection problem of yellow smoke emission in existing treatment is thoroughly solved.

A reflective integrated electrochromic device, sequentially comprising: a first substrate layer (11), a working electrode layer (12), an integrated electrochromic layer (13), a counter electrode layer (14), and a second substrate layer (15), wherein the integrated electrochromic layer (13) comprises a metal source compound, the metal source compound being selected from one or more of silver chloride, silver acetate, silver nitrate, silver perchlorate, silver sulfate, silver cyanide, silver sulfide, silver hexafluorophosphate, silver tetrafluoroborate, silver tetrachloroaluminate, silver triflate, silver bistrifluoromethanesulfonimide, copper fluoride, copper chloride, copper cyanide, copper sulfate, copper acetate, copper aluminate, cuprous fluoride, cuprous chloride, cuprous cyanide, gold chloride, gold cyanide, gold sulfide, gold monochloride, aurous sulfide, nickel chloride, nickel sulfate, cobalt chloride, and platinum chloride. The dynamic change range of the transmittance / reflectance of the device is relatively large, and the device can achieve simultaneous management of light and heat, and can maintain a stable colored or faded state for one month, or even several months, under no-load conditions.

This application relates to the field of environmental monitoring and water quality analysis technology, and in particular to a mixed reagent, test reagent tube, and digestion method for COD detection of petrochemical wastewater. The components, by mass percentage, are: sulfuric acid 75.0–90.0%, potassium dichromate 0.5–1.0%, silver sulfate 1.0–2.7%, scandium sulfate 0.01–0.07‰, potassium hydrogen phthalate 0.1–0.25‰, glucose 0.1–0.25‰, with the remainder being pure water; the mixed reagent does not contain mercuric sulfate. This application enables mercury-free and highly efficient digestion of high-salt, high-organic-content petrochemical wastewater, improves the oxidation efficiency of benzene compounds and polycyclic aromatic hydrocarbons, reduces the detection limit to below 5 mg / L, and the wastewater is easy to treat, combining high accuracy with environmental friendliness.

The invention discloses a high chloride ion wastewater COD (Chemical Oxygen Demand) determination method which comprises the following steps: preparing silver nitrate standard solutions with different concentrations according to the chloride ion concentration in high chloride ion wastewater; taking a high chloride ion wastewater sample, and titrating with a silver nitrate standard solution until brick-red precipitate is generated; filtering the titrated water sample, metering the volume of the filtrate after filtration, and calculating the dilution ratio N according to the volume of the filtrate, N = the volume of the filtrate / the sampling volume of the chloride ion wastewater sample; preparing a COD (Chemical Oxygen Demand) digestion prefabricated reagent, and mixing a potassium dichromate standard solution with a sulfuric acid-silver sulfate solution; and uniformly mixing the filtrate with a COD digestion prefabricated reagent, carrying out heating digestion, cooling to obtain a digestion solution, measuring the COD measurement value of the digestion solution, and calculating the COD of the high chloride ion wastewater. The COD of the water sample can be directly measured after preliminary simple treatment, a masking agent mercury sulfate is avoided, use of the mercury sulfate is saved, and errors are reduced.

The invention belongs to the technical field of silver sulfate processing, and particularly relates to a silver sulfate processing device, a liquid inlet adjusting mechanism and an adjusting method. Wherein the liquid inlet mechanism comprises at least one liquid inlet pipe, and a liquid outlet is formed in the outer wall of the liquid inlet pipe; each liquid inlet adjusting mechanism is arranged in the corresponding liquid inlet pipe, and each liquid inlet adjusting mechanism comprises a moving part, the upper end face of the moving part is suitable for buffering liquid flowing from top to bottom in the liquid inlet pipe when the moving part slides to the position below the liquid outlet in the liquid inlet pipe; and the moving part is suitable for blocking the liquid outlet when sliding to the position coplanar with the liquid outlet.

The invention discloses a method for preparing superfine silver powder by taking sulfate radical as a protective agent, which comprises the following steps: (1) precipitation: adding sulfuric acid into a silver nitrate aqueous solution, mixing, and performing solid-liquid separation to obtain silver sulfate precipitate and a mixed acid solution containing nitric acid and sulfuric acid; (2) circulation: adding the silver block into a mixed acid solution, and heating and stirring until the silver block is dissolved; (3) dissolving: adding the silver sulfate precipitate into an ammonia water solution to obtain a clear silver ammonia solution; and (4) reduction is conducted, specifically, the reducing agent solution is added into the silver-ammonia solution in the stirring state, filtering is conducted after stirring, sediment is cleaned till the conductivity is smaller than 25 microseconds / cm, and superfine silver powder is obtained after drying and powder screening are conducted. Sulfuric acid is introduced to precipitate silver ions in the silver nitrate solution, cyclic utilization of the nitrate solution is achieved, the production cost is reduced, the silver nitrate solution serves as a protective agent in the reduction preparation process of the silver powder, agglomeration and oxidation of the silver powder are effectively prevented, and the sphericity degree of the silver powder is good, and particle size distribution is uniform.

The invention discloses a silver sulfate purification method and circulation system, and the purification method comprises the following steps: S1, adding silver carbonate into industrial silver sulfate slurry, carrying out gradient temperature control and stirring reaction until the pH value of the system is neutral, and obtaining deacidified slurry; s2, carrying out solid-liquid separation on the deacidified slurry to obtain a purified silver sulfate solid and a silver-containing mother solution; s2, the silver-containing mother liquor is subjected to electrolysis-carbonation treatment, regenerated silver carbonate is obtained, and the regenerated silver carbonate is reused in the step S1; according to the method, acid impurities are converted into silver sulfate in a targeted mode through silver carbonate, a silver resource closed-loop cycle is formed by coupling a mother liquor electrolysis-carbonation regeneration technology, silver carbonate is used as an acid removing agent, sulfuric acid is accurately removed and converted into silver sulfate in situ, a by-product CO2 is decomposed to drive reaction kinetics, and silver sulfate is obtained. Acid impurities in industrial silver sulfate are efficiently removed, closed-loop recovery of silver resources is achieved, and the production cost and environmental pollution are reduced.