68 results about "Sodium thiocyanate" patented technology

The invention provides a gold leaching agent for treating high-carbon gold-bearing minerals and a gold leaching process, and belongs to the technical field of hydrometallurgy. According to the gold leaching agent, guanidinium thiocyanate is used as an agent main body, a hydroximic acid compound is used as a complexing synergist, and soluble inorganic salt of ferric iron is used as a competitive adsorbent. In a leaching system, guanidine thiocyanate can be decomposed to generate guanidine, sodium sulfide, sodium thiocyanate and water. Thiourea anions are converted into cyanamide under the alkaline condition, then cyanamide is slowly released and decomposed into cyanide ions, the cyanide ions are complexed with gold ions, and gold leaching is achieved. Namely, guanidinium thiocyanate has the effect of releasing the cyanide ions step by step, and slow release of the cyanide ions is realized. The gold leaching agent system does not contain cyanide (sodium cyanide, potassium cyanide and the like) and is a clean and environment-friendly agent system, and efficient leaching of gold in high-carbon gold-bearing minerals can be achieved through the synergistic effect of all functional agent components.

The present invention discloses a low-temperature resistant and early-strength type alkali-free liquid accelerating agent and its preparation method, belonging to the technical field of alkali-free liquid accelerating agents. The composition includes 12-15 parts of aluminum sulfate, 2-5 parts of sodium thiocyanate embedded by β-cyclodextrin, 5-8 parts of calcium hydroxide deactivator, 3-5 parts of fiber, 5-10 parts of hydrophilic polymer substance, 3-5 parts of cationic surfactant, 6-10 parts of polyaluminum chloride, and 2-3 parts of air-entraining agent. The low-temperature resistant and early-strength type alkali-free liquid accelerating agent of the present invention can improve the frost resistance of sulfate alkali-free accelerating agents, reduce the viscosity of cement slurry, promote the hydration reaction of C3S, shorten the setting time of concrete, and improve the later strength of concrete.

The invention relates to a method for separating sodium sulfate and sodium thiocyanate from a mixed waste salt solution, which comprises the following steps: carrying out catalytic oxidation, decoloration treatment and first solid-liquid separation on the mixed waste salt solution, and carrying out first evaporation concentration, first cooling crystallization and second solid-liquid separation on the obtained pretreated solution to obtain a sodium sulfate crude product and a filtrate, washing the sodium sulfate crude product, and carrying out third solid-liquid separation to obtain sodium sulfate; carrying out second evaporation concentration on the filtrate, adding sodium thiocyanate seed crystal, carrying out second cooling crystallization and fourth solid-liquid separation to obtain a sodium thiocyanate crude product and residual liquid, washing the sodium thiocyanate crude product, and carrying out fifth solid-liquid separation to obtain sodium thiocyanate; and circulating the washing waste liquid and the residual liquid to the pretreatment solution for mixing and recycling. According to the method, evaporation concentration is combined with cooling crystallization, sodium sulfate and sodium thiocyanate which are high in purity and extraction rate can be obtained through separation, and the whole preparation process is low in energy consumption and more environmentally friendly and integrally has good economic benefits.

The utility model discloses a sodium thiocyanate anti-caking stock bin which comprises a bin body with a discharging port formed in the bottom, a feeding port and a mounting hole are formed in the top of the bin body, a dehumidification device is arranged in the mounting hole and comprises a filter screen, a sealing plate, a motor, auger blades and super absorbent resin particles, the sealing plate is in flange connection with the mounting hole, the filter screen is of a cylindrical structure, and the motor is connected with the motor. The top of the filter screen is fixedly connected with the lower surface of the sealing plate, the motor is installed on the sealing plate, the auger blade is located in the filter screen, the outer diameter of the auger blade is smaller than the diameter of the filter screen, the motor drives the auger blade to rotate, and the super absorbent resin particles are located in the filter screen. The moisture absorbent is arranged to adsorb moisture in the bin body, and the problem that sodium thiocyanate absorbs water and hardens is prevented.

The invention discloses premixed flow-state solidified soil and a preparation method thereof, and the premixed flow-state solidified soil comprises the following components in parts by weight: 100 parts of silty clay; 8 to 15 parts of a curing agent; 48 to 90 parts of water; wherein the curing agent comprises the following components: 10 to 15 parts of sulphoaluminate cement; 40 parts to 55 parts of superfine steel slag powder; 30 to 40 parts of fly ash; 0.5 to 1.5 parts of sodium silicate; 0.1 to 0.3 part of a foaming agent; 0.1 part to 0.2 part of sodium thiocyanate; 0.1 part to 0.2 part of hydroxymethyl cellulose; 0.05 part to 0.2 part of triisopropanolamine; 0.1 part to 0.5 part of calcium nitrate; and 0.5 to 1 part of a polycarboxylic acid water reducing agent. The preparation method of the premixed flow-state solidified soil is suitable for using silty clay as a raw material, and greatly improves the strength, compactness, fluidity and other properties of the premixed flow-state solidified soil.

The invention discloses an MOFs adsorbent of cumene and a preparation method and application thereof, and belongs to the technical field of adsorbent preparation, and the preparation method comprises the following steps: step 1, preparing an MIL-101 adsorbent; 2, the MIL-101 adsorbent is soaked in a thiocyanate solution for 10 min to 30 min, centrifugation, washing and drying are conducted, and the MOFs adsorbent of isopropyl benzene is obtained. The adsorption capacity of the MIL-101 adsorbent post-treated by the sodium thiocyanate to cumene gas is remarkably improved. Due to the introduction of sodium thiocyanate, a new functional group is grafted, and a new adsorption site is introduced, so that the adsorption capacity of the adsorbent on cumene gas is remarkably improved.

The invention discloses a low-carbon cementing material for coal mine paste filling, and belongs to the technical field of coal mine filling. The invention discloses a low-carbon cementing material for coal mine paste filling. The low-carbon cementing material comprises the following raw materials in parts by mass: 200-240 parts of furnace slag, 50-80 parts of carbide slag, 40-65 parts of desulfurized gypsum, 330-360 parts of fly ash, 10-20 parts of an active activator and 5-10 parts of a coagulant, wherein the active exciting agent is a mixed compound of sodium aluminate and sodium orthosilicate; the coagulant is a mixed compound of sodium thiocyanate and anhydrous calcium chloride. The cementing material adopts all solid waste raw materials, can be used for preparing a coal mine paste filling material, can reduce the filling cost of coal mining, improves the working efficiency of coal mining, and is beneficial to promoting the healthy and sustainable development of coal mine enterprises.

The invention provides a preparation method and device of prothioconazole. The preparation method comprises the following steps: carrying out Grignard reaction on o-chlorobenzyl chloride and magnesium powder in a mixed solvent of toluene and 2-methyltetrahydrofuran; the method comprises the following steps: carrying out Grignard addition reaction on a Grignard reagent and 2-chloro-1-(1-chlorocyclopropyl) ethanone; the preparation method comprises the following steps: carrying out substitution reaction on 1-chloro-2-(1-chlorocyclopropyl)-3-(2-chlorphenyl) propanol and hydrazine hydrate in an alcohol solvent; the preparation method comprises the following steps: carrying out ring closing reaction on 2-(1-chlorocyclopropyl)-1-(2-chlorphenyl)-3-hydrazino-2-alcohol, a formaldehyde solution, a sodium thiocyanate solution and a sodium hydrogen sulfate solution; the preparation method comprises the following steps: carrying out oxidation reaction on 2-(2-chlorocyclopropyl)-3-(2-chlorphenyl)-2-hydroxypropyl)-1, 2, 4-triazolidine-3-thioketone, air and inorganic alkali, so as to obtain prothioconazole. The method can improve the efficiency of the oxidation reaction and the yield and purity of prothioconazole, and is more suitable for industrial production of prothioconazole.

The present invention relates to the field of textile chemicals and high-performance fiber technology, and specifically to a polyacrylonitrile spinning solution, a preparation method thereof, and an application thereof. The preparation method of the polyacrylonitrile spinning solution comprises the following steps: (1) mixing a polyacrylonitrile resin with a first sodium thiocyanate aqueous solution at a temperature of 10 to 25°C, and dispersing and beating at a temperature of 15 to 25°C to form a slurry mixture; (2) mixing the slurry mixture with a second sodium thiocyanate aqueous solution at a temperature of 100 to 140°C, and then high-speed shearing at a temperature of 80 to 90°C to obtain a polyacrylonitrile spinning solution; the polyacrylonitrile resin has a number average particle size of 2 to 9 um, a particle size distribution index of 1.5 to 2.8, and a sedimentation value of 3.0 to 4.2. According to the preparation method of the present invention, the slurry viscosity in the preparation process of the polyacrylonitrile spinning solution is low, the fluidity is good, and it can be used for continuous production, and the prepared polyacrylonitrile spinning solution has a high solid content, a low viscosity, and good extrusion uniformity and stability.

The invention discloses a low-temperature-resistant early-strength alkali-free liquid accelerator and a preparation method thereof, and belongs to the technical field of alkali-free liquid accelerators, the low-temperature-resistant early-strength alkali-free liquid accelerator comprises 12-15 parts of aluminum sulfate, 2-5 parts of beta-cyclodextrin embedded sodium thiocyanate, 5-8 parts of a calcium hydroxide inactivator, 3-5 parts of fiber, 5-10 parts of a hydrophilic polymer substance, 3-5 parts of a cationic surfactant, 6-10 parts of polyaluminum chloride, and 2-3 parts of an air entraining agent. The low-temperature-resistant early-strength alkali-free liquid accelerator can improve the frost resistance of a sulfate alkali-free accelerator, reduce the viscosity of cement paste, promote the hydration reaction of C3S, shorten the setting time of concrete and improve the later strength of the concrete.

The present invention relates to a modification and regeneration method of waste activated carbon, belonging to the technical field of activated carbon, and the method comprises the following steps: S1, preparing an intermediate material; S2, preparing modified carbon; S3, preparing an activated carbon product. The present invention adopts zinc chloride and sodium thiocyanate to synergistically activate the waste activated carbon, effectively activates and forms pores, and increases the active sites on the surface of the activated carbon. On this basis, it is compounded with steel slag micropowder and ferrocene, which effectively increases the adsorption capacity of the obtained activated carbon. Therefore, the activated carbon thus obtained has an excellent desulfurization and denitrification effect; in addition, the present invention also makes a self-made adhesive for the bonding of activated carbon, and polyvinyl acetate is added in the process of preparing the adhesive, and its certain bonding property increases the strength of the prepared adhesive; anhydrous borax is added to improve the density of the network structure in the system, and the adhesive and the activated carbon are cross-mixed to form a tight whole, thereby enhancing the compressive strength of the obtained activated carbon.

The invention provides an anti-permeability and anti-sulfate corrosion additive for organic nano concrete, and belongs to the technical field of concrete. The additive disclosed by the invention contains ethylenediamine methylene sodium phosphate, sodium polyacrylate, sodium thiocyanate, polylactic acid-glycolic acid copolymer (PLGA), hydroxypropyl ethanolamine, a modified nano graphite material, chitosan quaternary ammonium salt, a silane coupling agent, nano volcanic ash powder and other components in a specific proportion. Wherein the modified nano-graphite material is prepared by modifying nano-graphite powder with polyether amine and a silane coupling agent; all the components are matched and the additive is prepared by adopting a special preparation method, and the additive has good impermeability and sulfate corrosion resistance when being used in concrete, and is stable and reliable.

The present invention discloses a method for synthesizing diafenthiuron, which comprises: in the presence of an organic acid or an organic base, a compound represented by formula (I) and a compound represented by formula (II) are subjected to a condensation reaction to obtain diafenthiuron. In the present invention, in the presence of an organic base or an organic carboxylic acid, the compound represented by formula (I) and the compound represented by formula (II) are subjected to condensation reaction to prepare diafenthiuron, and the conversion rate and selectivity are high. Compared with the sodium thiocyanate method, the method provided by the present invention has a short process step, avoids high-temperature thermal decomposition reaction, improves process safety, is suitable for industrial production, and has broad application prospects.

The invention discloses a method for measuring the content of sodium thiocyanate in milk, which comprises the following steps: firstly, at least carrying out deproteinization treatment on a milk sample to be measured to obtain a pretreated sample; secondly, uniformly mixing the pretreated sample with a ferric salt solution to form a mixed sample, fully reacting the mixed sample in a static magnetic field, and then detecting the light absorption value of the obtained reaction mixture at the wavelength of 455 nm in the static magnetic field; and then calculating the content of sodium thiocyanate in the milk sample to be detected according to the light absorption value and a standard curve formula. Compared with the prior art, the detection method provided by the invention has the advantages of high precision, sensitivity and accuracy, simplicity in operation, good safety and the like.

The utility model discloses a sodium thiocyanate anti-caking device, and relates to the technical field of sodium thiocyanate. Comprising a stirring barrel, a stirring assembly is arranged in the stirring barrel, the top face of the stirring barrel is fixedly connected and communicated with a feeding pipe, a discharging opening is formed in the center of the bottom face of the stirring barrel, the discharging opening is fixedly connected and communicated with a first conveying auger, and the end, away from the discharging opening, of the first conveying auger is fixedly connected and communicated with a second conveying auger; the end, away from the first conveying auger, of the second conveying auger is fixedly connected and communicated with the top face of the stirring barrel through a second discharging pipe, and the first conveying auger and the second conveying auger are perpendicular to each other. According to the utility model, the first conveying auger, the second conveying auger and the mixing drum form a circulating state, so that sodium thiocyanate circularly flows in the mixing drum, the first conveying auger and the second conveying auger, and the sodium thiocyanate can be in a loose state; and the phenomenon that the sodium thiocyanate is mutually extruded from a loose state to form a block mass due to long-term stacking and stacking extrusion is effectively avoided.

The invention discloses a self-cleaning filter for processing a sodium thiocyanate product and a use method, and relates to the technical field of chemical equipment. The filtering machine comprises a shell, a feeding pipe, a filtering tank, a filtering plate and a containing and receiving disc, and further comprises a lifting mechanism, a stirring mechanism, an overturning driving mechanism, a vibrating mechanism, a moving mechanism and a mounting mechanism. The lifting mechanism consists of a cylinder on the upper side of the shell and a lifting plate connected with the lower end of a piston rod; the stirring mechanism is arranged on the lifting plate and used for stirring materials in the filter tank; the overturning driving mechanism is connected with the filter tank and drives the filter tank to overturn and pour impurities; the vibration mechanism acts on the filter tank and assists in discharging residual impurities; the moving mechanism is arranged at the lower end in the shell and drives the containing disc to move horizontally. The mounting mechanism is connected with the moving mechanism and the containing disc, and the containing disc is detachably mounted. The at least two containing discs can be switched between the inner station and the outer station through the moving mechanism, and automation and high efficiency of the sodium thiocyanate processing and filtering link are achieved.

The invention provides a method for preparing a repair material for hydraulic concrete by using a solid waste material. The preparation method comprises the following steps: mixing 55-65% of a material A (water-quenched slag and copper slag), 30-40% of a material B (citric acid gypsum, red mud and spontaneous combustion coal gangue) and 4-6% of a catalytic complexing activator (cane molasses, iron ion catalytic complexing agent sodium thiocyanate leftovers, polyether amine, calcium ion catalytic complexing agent diisopropanolamine borate and water), and carrying out ball milling to obtain the concrete; the repairing material and water are uniformly stirred according to the ratio and then are brushed or sprayed on the base surface of the defective concrete, so that the effects of resisting scouring, resisting erosion and freezing and thawing can be achieved, the effect of further cracking and falling off of the concrete is inhibited, and the durability of the hydraulic concrete is improved.

The present invention relates to a method for separating sodium sulfate and sodium thiocyanate from a mixed waste salt solution. The method comprises subjecting the mixed waste salt solution to catalytic oxidation, decolorization, and a first solid-liquid separation, then subjecting the obtained pretreatment solution to a first evaporation concentration, a first cooling crystallization, and a second solid-liquid separation to obtain a crude sodium sulfate product and a filtrate, washing the crude sodium sulfate product, and subjecting the pretreatment solution to a third solid-liquid separation to obtain sodium sulfate; subjecting the filtrate to a second evaporation concentration, adding sodium thiocyanate seed crystals, and then subjecting the pretreatment solution to a second cooling crystallization and a fourth solid-liquid separation to obtain a crude sodium thiocyanate product and a residual liquid, washing the crude sodium thiocyanate product, and subjecting the pretreatment solution to a fifth solid-liquid separation to obtain sodium thiocyanate; and recycling the washing waste liquid and the residual liquid to the pretreatment solution for mixing and reuse. The present invention utilizes evaporation concentration combined with cooling crystallization to separate sodium sulfate and sodium thiocyanate with high purity and extraction rate. The entire preparation process has low energy consumption, is more environmentally friendly, and has good overall economic benefits.

The present application belongs to the technical field of adsorbents, and relates to a kind of for adsorbing and settling palladium amidoxime polyacrylonitrile-based microspheres and preparation method thereof.The present application utilizes chitosan quaternary ammonium salt (Q-CS), polyacrylonitrile (PAN) and sodium thiocyanate-containing amidoxime polyacrylonitrile (PAO / NaSCN) to obtain palladium adsorption performance stable amidoxime polyacrylonitrile microspheres;Among them, amidoxime and functional groups such as hydroxyl, amino and the like in chitosan can play the role of palladium adsorption, thiocyanate in sodium thiocyanate plays the role of settlement, and polyacrylonitrile enhances the mechanical strength of microspheres.The microspheres can adsorb and settle nearly 76% of palladium ions in solution within 5min at room temperature, reach adsorption and settlement equilibrium after 600min, and the adsorption capacity can reach 242mg / g when adsorption and settlement reach saturation.

The invention discloses sludge-soil-based flow-state solidified soil and a preparation method thereof.The method comprises the steps that 1, potassium ferrate, sodium hydroxide, sodium tripolyphosphate and water are added into sludge soil and stirred and mixed, and sludge soil slurry is obtained; the mass of the potassium ferrate is 0.2%-0.7% of the mass of the mucky soil; 2, a curing agent and water are added into the mucky soil slurry, stirring and mixing are conducted, and flow-state solidified soil is obtained; the curing agent comprises sulphoaluminate cement, Portland cement, steel slag powder, fly ash, a plasticizer, sodium thiocyanate, calcium formate and sodium silicate. By adopting the preparation method disclosed by the invention, the shrinkage of the cured mucky soil can be reduced, the stable improvement of the curing strength of the early-stage, middle-stage, later-stage and long-term fluid-state cured soil is ensured, and the flowability of the fluid-state cured soil is improved.

The utility model discloses a sodium thiocyanate continuous production device which comprises a base, a feeding port is formed in the upper portion of the base, a screen is arranged between the feeding port and a discharging baffle, a fixing seat is arranged on the base, a first pressing frame and a second pressing frame are arranged on the fixing seat, the first pressing frame and the second pressing frame are both connected with the fixing seat in a sliding mode, and the first pressing frame and the second pressing frame are connected with the base in a sliding mode. A fixing block is arranged below the fixing seat, a sliding rod is arranged in the base, a spring is connected to the sliding rod in a sleeving mode, a cam is arranged on the base, two sets of symmetrically-distributed fixing frames are arranged on the base, and cleaning brushes are arranged on the fixing frames. The winding rod, the expansion roller and the like are matched with the first pressing frame and the second pressing frame to achieve timing transmission conversion of the screen, so that it is guaranteed that the screen is in the maximum filtering efficiency state when filtering sodium thiocyanate for a long time, and continuous production and production efficiency of sodium thiocyanate are guaranteed; and a worker does not need to regularly stop the production work of sodium thiocyanate to replace the screen.

The utility model discloses a sensor-based device for detecting furfural in insulating oil, which comprises a furfural sensor, a data processing module and a communication interface, the data processing module is simultaneously in communication connection with the furfural sensor and the communication interface, and a detection signal of the furfural sensor is transmitted to the data processing module for data processing. The processed detection signal is transmitted to external equipment through the communication interface; the furfural sensor comprises a reaction tank and a color sensor located at the top end of the reaction tank, an acidic sodium thiocyanate solution is contained in the reaction tank, and a detection signal corresponds to a detection value of the color sensor. According to the furfural detection device, the furfural concentration is determined by utilizing the reaction tank and the color sensor, the detection device is low in cost, furfural content detection and detection signal processing and transmission can be accurately realized, the application range of the furfural detection device is widened, and the detection cost is reduced.

The application discloses a homogenous-heterogeneous dual junction coupled photocatalyst and a preparation method and application thereof. The preparation method of the homogenous-heterogeneous dual junction coupled photocatalyst comprises the following steps: mixing carbon nitride, lithium chloride and potassium chloride to obtain mixed powder, calcining the mixed powder, cooling and washing, and drying to obtain a precursor; mixing the precursor, ammonium chloride and sodium thiocyanate, grinding to obtain a mixture, calcining the mixture, cooling and washing, and drying to obtain homogenous junction carbon nitride; dispersing ferric chloride hexahydrate and sodium acetate in ethanol, adding H2O drop by drop to obtain a mixed solution, adding the homogenous junction carbon nitride into the mixed solution, ultrasonicating to obtain a dispersion liquid, heating the dispersion liquid, cooling and washing, and drying to obtain the homogenous-heterogeneous dual junction coupled photocatalyst; and the removal rate of the homogenous-heterogeneous dual junction coupled photocatalyst to TC is 99.8% within 20 min, the problem that the heterojunction is limited by the influence of acid and alkalinity is solved, and the pH application range of the photocatalyst is widened.

The invention discloses a stainless steel blackening agent and a preparation and application method thereof, and belongs to the technical field of chemical materials. Based on 1 * 10 < 3 > parts of stainless steel blackening agent, the stainless steel blackening agent comprises the following raw materials in parts by weight: 350-450 parts of strong base, 75-85 parts of sodium thiocyanate, 35-45 parts of sodium thiosulfate, 3-6 parts of stabilizer, 0.1-0.3 part of corrosion inhibitor and the balance of water. The invention further discloses a preparation method and an application method of the stainless steel blackening agent. According to the stainless steel blackening agent, the problems that an existing blackening agent is high in chromium concentration, large in environmental influence, complex in treatment method and uneven in black film layer can be solved, and the black film layer formed by the stainless steel blackening agent is even and bright, good in abrasion resistance and corrosion resistance and small in environmental influence.

The invention discloses a neodymium-iron-boron trivalent chromium plating method with a triple electrochemical protection effect and a plating layer structure. The method comprises the step of sequentially preparing a cyanide-free copper-zinc alloy plating layer, a cyanide-free copper plating layer, a nickel-copper alloy plating layer, a semi-bright nickel plating layer, a nickel-cobalt alloy plating layer, a trivalent chromium plating layer and a rare earth electrolysis protection film on a neodymium-iron-boron substrate. According to the process for preparing the cyanide-free copper plating layer, 18-24 g / L of polycuprous thiocyanate, 130-170 g / L of polysodium thiocyanate, 20-30 g / L of sodium hydroxyethylidene diphosphonate and 8-12 mL / L of a copper plating brightener are adopted, the pH value of a plating solution is 12-13, the temperature of a plating tank is 30-40 DEG C, the cathode current density is 0.5-1.5 A / dm < 2 >, the cathode movement speed is 3-5 m / min, oxygen-free electrolytic copper particles serve as an anode, and the anode movement speed is 3-5 m / min. The surface of the prepared trivalent chromium-plated sample piece is not rusted after being subjected to a neutral salt spray test for 142 hours according to the GB / T 10125-2021 standard.

The application discloses a FeNi2P / PCN-NaCA photocatalyst and a preparation method and application thereof, belongs to the field of photocatalysts, and solves the problem of the restriction of existing carbon nitride materials on the hydrogen peroxide production efficiency of photocatalysis. The preparation method comprises the following steps: dissolving iron chloride, nickel nitrate and terephthalic acid in N,N-dimethylacetamide, and performing a hydrothermal reaction to obtain a FeNi2P precursor; heating the FeNi2P precursor and anhydrous sodium phosphate in a nitrogen atmosphere to obtain FeNi2P; calcining melamine to obtain PCN; and mixing the PCN, sodium thiocyanate solid and FeNi2P, and calcining in a nitrogen atmosphere to obtain the FeNi2P / PCN-NaCA photocatalyst. The FeNi2P / PCN-NaCA photocatalyst can efficiently utilize light to produce hydrogen peroxide, and has the characteristics of good stability and reusability.

The invention relates to the technical field of salt extraction and recovery of sodium-process desulfurization waste liquid, in particular to a method and device for extracting product-grade sodium thiocyanate from sodium-process desulfurization waste liquid, and the method comprises the following steps: step a, primary decoloring treatment, step b, primary concentration crystallization, step c, secondary decoloring treatment, step d, freezing crystallization, step e, precise desalting, and step f, secondary concentration crystallization. A stepped process design of two-time decoloration, fractional crystallization and precise desalination is adopted, aiming at the physicochemical property difference of three core salts of sodium sulfate, sodium thiosulfate and sodium thiocyanate in the sodium-process desulfurization waste liquid, efficient separation is realized by accurately controlling process parameters, the sodium sulfate is preferentially separated out by utilizing the characteristic that the solubility of the sodium sulfate is relatively low at high temperature, and the sodium thiosulfate is separated out by utilizing a high-temperature crystallization method. The sodium thiocyanate is separated out in a targeted manner on the premise of ensuring that the sodium thiocyanate is in an unsaturated state, so that the technical problem that the sodium thiocyanate is easy to co-crystallize at low temperature is solved.

This invention relates to the field of oilfield chemical technology, and discloses a low-molecular-weight, high-viscosity ternary polymer flooding agent, its preparation process, and its application. The low-molecular-weight, high-viscosity ternary polymer flooding agent comprises the following raw materials by weight: simulated formation water: 986.2-995.9 g; sodium thiocyanate: 0.2-1.2 g; partially hydrolyzed polyacrylamide: 1.0-3.0 g; dodecyl hydroxypropyl sulfobetaine: 2.0-6.0 g; sodium salicylate: 0.9-3.6 g. The simulated formation water is prepared from deionized water, sodium chloride, calcium chloride, and magnesium chloride. Sodium thiocyanate is added to the simulated formation water to obtain a basic conditioning fluid; partially hydrolyzed polyacrylamide is added to obtain a polymer-based fluid; dodecyl hydroxypropyl sulfobetaine is added to obtain a mixed solution; and sodium salicylate is added to induce a rheological property transformation. This invention constructs a double interpenetrating network structure, solving the problems of insufficient viscosity enhancement and poor plugging.

The application discloses a high-performance concrete special antifreeze for severe cold regions and cold-resistant high-performance concrete, and the raw materials of the antifreeze include 6-10 parts of sodium thiocyanate, 5-8 parts of calcium nitrate, 7-10 parts of a composite phase change material, 3-5 parts of nano calcium carbide slag powder and 3 parts of sodium citrate in terms of mass fraction. The raw materials of the high-performance concrete include 330-360 parts of ordinary Portland cement, 60-90 parts of fly ash, 630-660 parts of fine aggregate, 1150-1200 parts of coarse aggregate and 8-10 parts of high-performance polycarboxylic acid water reducing agent in terms of mass fraction; and the high-performance concrete special antifreeze for severe cold regions is further included and the dosage is 7.5-9 parts. The antifreeze provided by the application is specially applied to severe cold regions (temperature fluctuation reaches-15 DEG C to-5 DEG C, and even reaches-20 DEG C in extreme regions), and in addition to antifreezing and early strength promotion, the working performance of concrete is ensured, the compressive strength of the concrete added with the antifreeze reaches 58.2 MPa, and the compressive strength loss after 200 freeze-thaw cycles is only 1.2-1.4%.

The invention discloses a magnesium alloy gold plating method with triple electrochemical protection effects and a plating layer structure. The process comprises the following steps: sequentially preparing a chemical zinc deposition layer, a cyanide-free copper-tin alloy plating layer, a cyanide-free copper-zinc alloy plating layer, a bright nickel-copper alloy plating layer, a nickel-phosphorus alloy plating layer, a gold plating layer and an anti-discoloration protective film on a magnesium alloy substrate. According to the cyanide-free copper-tin alloy plating process, 18-24 g / L of polycuprous thiocyanate, 0.2-0.6 g / L of stannous oxalate, 130-170 g / L of polysodium thiocyanate, 20-30 g / L of sodium 1-hydroxyethylidene-1, 1-diphosphonate and 8-12 mL / L of a copper-tin alloy plating brightener are adopted, the pH value of a plating solution is 12-13, the temperature of a plating tank is 30-40 DEG C, the cathode current density is 0.5-1.5 A / dm < 2 >, the cathode movement speed is 3-5 m / min, oxygen-free electrolytic copper particles serve as an anode, the copper particles are loaded into a titanium anode basket, the area ratio of the anode to the cathode is larger than 3: 1, and the anode movement speed is 3-5 m / min. And the surface of a plated part is not rusted after the plated part is subjected to an acetate mist test for 200 hours according to the GB / T 10125-2021 standard.