44 results about "Sodium thiocyanate" patented technology

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 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 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 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 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 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 relates to the technical field of concrete admixtures, and particularly discloses a steam-cured aerated concrete admixture as well as a preparation method and application thereof, and the steam-cured aerated concrete admixture comprises the following components in parts by mass: 12-15 parts of polyoxyethylene laurate; 5-8 parts of lithium sulfate; 20 to 25 parts of triethanolamine; 4 to 7 parts of sodium thiocyanate; 5-10 parts of a water reducing agent; and 40-60 parts of a solvent. The method has the advantage that the production cost of the AAC block is reduced so as to improve the economic value of the AAC block.

The invention provides an ammonia separation process for ammonia synthesis and an ammonia synthesis process. According to the process, product gas obtained by ammonia synthesis exchanges heat with ammonia synthesis gas and then is input into an ammonia separation process; in the ammonia separation process, a lean working medium absorbs ammonia in the product gas to obtain a rich working medium, and residual gas after ammonia absorption is mixed with ammonia synthesis gas for recycling; an ammonia product is output after the rich working medium passes through a hydraulic turbine, flash evaporation and desorption processes, and an obtained lean working medium is returned to the ammonia separation process; wherein the working medium is an ammonia solution containing calcium chloride, sodium thiocyanate and sodium tripolyphosphate. According to the invention, a special working medium is adopted to absorb separated ammonia and desorb the output ammonia product, so that the separation of ammonia in the synthesis ammonia product gas is realized, the process flow is simplified, and the energy consumption is obviously reduced; the residual pressure in the ammonia synthesis process is fully utilized for power generation, heat in the technological process is fully recycled, and the energy utilization efficiency is high.

The invention relates to the field of metal surface treatment, and particularly discloses a gray passivation solution for zinc alloy and a passivation method. The gray passivation solution for the zinc alloy comprises the following components: 60-85 g / L of nickel chloride hexahydrate, 60-75 g / L of sodium thiocyanate, 5-10 g / L of ammonium chloride, 20-30 g / L of chromic nitrate nonahydrate, 10-15 g / L of cobalt chloride hexahydrate, 15-20 g / L of monopotassium phosphate, 40-60 g / L of zinc dihydrogen phosphate, 80-110 mL / L of a zinc nitrate solution, 20-30 g / L of manganese dihydrogen phosphate and 0.05-0.2 g / L of a surfactant, and a solvent of the gray passivation solution for the zinc alloy is pure water. The content of zinc nitrate in the zinc nitrate solution is 300g / L. The gray passivation solution for the zinc alloy has the advantages of being uniform in coating film surface, high in binding force and resistant to abrasion and corrosion.

The invention relates to the technical field of organic synthesis, and provides a continuous synthesis method of 1-isothiocyanate-2-chloro-2-propylene, which comprises the following steps: S1, dissolving sodium thiocyanate in a mixed solvent, adding 2, 3-dichloropropene, and carrying out nucleophilic substitution reaction to obtain an oil phase and a saline water phase; s2, the oil phase is subjected to a rearrangement reaction, a 1-isothiocyanate-2-chloro-2-propylene crude product is obtained, rectification is carried out, and 1-isothiocyanate-2-chloro-2-propylene is obtained; s3, after the saline phase is extracted, an organic matter phase and a saline raffinate phase are obtained, an extracting agent in the organic matter phase is recycled to serve as a regeneration extracting agent to be reused in extraction treatment, desalting treatment is conducted on the saline raffinate phase, and a sodium chloride solid is obtained; the mixed solvent is water and polyhydric alcohol. According to the technical scheme, the problem of low yield of the 1-isothiocyanate-2-chloro-2-propylene in the prior art is solved.

The invention discloses a thiophanate-methyl synthesis method, and relates to the technical field of pesticide synthesis, and the thiophanate-methyl synthesis method comprises the following steps: S1, dissolving sodium thiocyanate in water, adding a catalyst, adding methyl chloroformate, and after the reaction is finished, carrying out liquid separation to obtain methyl isothiocyano formate; s2, methyl isothiocyano formate is added into 1, 2-dichloroethane, and a methyl isothiocyano formate solution is obtained; the preparation method comprises the following steps: adding o-phenylenediamine into 1, 2-dichloroethane, stirring and dissolving, dropwise adding into a methyl isothiocyano formate solution, keeping the temperature to react for 30-60 minutes, cooling and crystallizing, thereby obtaining the o-phenylenediamine methyl isothiocyano formate. The catalyst comprises modified dialkylaniline; the modified dialkylaniline comprises magnesium lithium silicate serving as a carrier, and further comprises dialkylaniline. The thiophanate-methyl synthesized by the method provided by the invention has high yield and content.

The invention belongs to the technical field of cement additives, and discloses a high-dosage industrial waste residue cement mineralization activity activator, which comprises a grinding aid and a mineralization enhancer, the grinding aid comprises bio-based alcohol amine, molasses, alpha-olefin sodium sulfonate and water; the mineralization enhancer comprises sodium thiosulfate, sodium thiocyanate, sodium formate and calcium sulfite type desulfurized gypsum. The cement mineralization activity exciting agent is applied to a cement grinding section, a grinding aid and a mineralization enhancer are synchronously doped, and the grinding aid and the mineralization enhancer form a synergistic superimposed effect, so that the technical problem of low 3d strength of cement is solved, and the strength of each age is stably improved by exciting the early hydration activity of the cement and a mixed material.

The application discloses a method for recovering cobalt from waste residues in the production of cobalt acetate by a hydrogen peroxide method, and adopts sodium thiocyanate and acetic acid to treat cobalt waste residues to obtain [Co(NCS)4] 2‑ solution, an oxide and unreacted metal cobalt; the obtained unreacted metal cobalt can be directly put into a synthesis kettle to participate in the production of cobalt acetate after being leached by sodium thiocyanate to remove surface impurities; the obtained oxide is reacted with sulfuric acid and hydrogen peroxide to obtain a cobalt sulfate solution; the obtained cobalt sulfate solution and the obtained [Co(NCS)4] 2‑ solution are reacted with sodium carbonate to obtain cobalt carbonate precipitation; the obtained cobalt carbonate precipitation is reacted with an acetic acid solution to obtain a cobalt acetate solution. The application does not produce toxic thiocyanic acid gas, and the sodium thiocyanate can be reused in the recovery process, so that the generation of waste liquid can be reduced, the cobalt recovery rate is high, and economic benefits are good.

The invention discloses a cleaning agent for online descaling. The cleaning agent is prepared from the following raw materials in parts by weight: 10 to 15 parts of modified microcline, 6 to 10 parts of octanol polyoxyethylene ether, 4 to 7 parts of sodium thiocyanate, 3 to 6 parts of sodium humate, 8 to 12 parts of modified tourmaline, 8 to 12 parts of deionized water and 2 to 4 parts of silane coupling agent KH560. According to the cleaning agent for online descaling, the octanol polyoxyethylene ether, the sodium thiocyanate and the sodium humate are matched with the modified microplagioclase and the modified tourmaline, balance improvement of the cleaning efficiency and the boiler corrosion protection performance of the obtained cleaning agent is achieved through blending and synergistic effects of the raw materials, and meanwhile the cleaning agent is remarkable in corrosion resistance and heat-resistant stability effect.

The present invention relates to a dry powder cement admixture, its preparation method and application. By mass percentage, it includes: sodium thiocyanate 4% - 8%, sodium thiosulfate 8% - 16%, organic alkanolamine 0.4 - 1.2%, polymer resin 16 - 32%, carrier 54 - 68%; the polymer resin contains sulfonic acid groups, acrylic acid groups, amide groups and graphene oxide. The technical problem to be solved by the present invention is how to provide a dry powder cement admixture that has good performance when used in combination with the concrete system of downstream suppliers; after significantly reducing the addition ratio of the cementitious material during concrete preparation, the strength of the concrete can still reach a good level, saving costs, and thus being more suitable for practical use.

The invention discloses mucky soil premixed flow-state solidified soil and a preparation method thereof.The method comprises the steps that 1, sodium thiocyanate, triisopropanolamine, a plasticizer, sulphoaluminate cement, Portland cement, steel slag powder, slag powder, fly ash and gypsum are stirred and mixed, and a curing agent is obtained; and step 2, adding the curing agent, the filling aggregate and water into the mucky soil, and stirring and mixing to obtain the flow-state solidified soil. The sodium thiocyanate, the sulphoaluminate cement and the gypsum cooperate to improve the early curing strength and reduce the shrinkage of the mucky soil during curing; portland cement improves the medium-term curing strength. The triisopropanolamine, the plasticizer, the steel slag powder and the slag powder cooperate to improve the later curing strength and improve the fluidity; the fly ash improves the long-term curing strength. All the components in the curing agent jointly play a synergistic role, the fluidity of the mucky soil is improved, the curing strength of the mucky soil is improved, and shrinkage during curing is reduced.

The invention discloses a low-cost T800-grade carbon fiber as well as a preparation method and application thereof. The preparation method comprises the following steps: polymerizing an acrylonitrile monomer, a comonomer, an initiator and a composite additive in a sodium thiocyanate aqueous solution to obtain a spinning solution; performing dry-jet wet spinning on the spinning solution to obtain nascent fibers; the nascent fiber is subjected to washing water drawing, drying densification, multi-stage steam drawing, pre-oxidation, carbonization and surface treatment, and the low-cost T800-grade carbon fiber is prepared. According to the invention, by adding the carbon nanotube and graphene composite additive, the initial temperature of pre-oxidation is reduced, and the energy consumption is reduced; and through a waste heat recovery system and process parameter optimization, the production cost and the energy consumption are reduced. The tensile strength of the prepared carbon fiber is larger than or equal to 5.8 GPa, the tensile modulus is larger than or equal to 295 GPa, the performance stability is high (the CV value is smaller than 4%), the cost is reduced by 30% compared with that of traditional T800-grade carbon fiber, and the carbon fiber is suitable for the fields of aerospace, wind power generation and the like.

The invention provides a combined catalyst and application thereof, and belongs to the technical field of fine chemical engineering. The combined catalyst consists of a phase transfer catalyst, an antioxidant and a buffering agent, the phase transfer catalyst is a crown ether phase transfer catalyst; the antioxidant is one or more of dilauryl thiodipropionate, disteaxyl thiodipropionate, triphenyl phosphate and pentaerythritol diphosphite ester; and the antioxidant is one or more of dibutyl thiodipropionate, disteaxyl thiodipropionate, triphenyl phosphate and pentaerythritol diphosphite ester. The buffering agent is one or more of potassium carbonate, sodium hydroxide and sodium bicarbonate. The combined catalyst is high in activity, and when the combined catalyst is used for a reaction for synthesizing sodium thiocyanate and chloropropyltriethoxysilane, the conditions are mild, the dosage of the combined catalyst is small, control is easy, operation is easy, the synthesis reaction time is short, the yield is high, few by-products are generated, the production cost is reduced, and the yield and quality of the product are improved.

The utility model discloses a kind of sodium thiocyanate solid-liquid separation equipment, including processing box, the top of processing box is passed through and is fixedly connected with its feed hopper, the inner wall of processing box is fixedly connected with separation frame, the bottom of feed hopper is fixedly communicated with the top of separation frame, the bottom of separation frame is passed through and is equipped with through opening, the inner wall of through opening is fixedly connected with screening net, the right side of separation frame is passed through and is equipped with discharge port. The utility model integrates solid-liquid filtration separation and solid drying function in the same main frame, without additional setting material transfer device or step-by-step operation process; through the collaborative design of hot air conveying and rotary stirring, hot air can be uniformly conveyed to the solid material area through the hollow structure, and the stirring assembly continuously turns the material during rotation, so that the hot air and the material are in full contact, effectively solving the problem of uneven local drying that easily occurs in traditional fixed drying structure.

The invention relates to the technical field of pesticide synthesis, and discloses a continuous synthesis method of thiophanate-methyl. The method comprises the following steps: preparing dry sodium thiocyanate into an aqueous solution, and continuously reacting with methyl chloroformate and a catalyst in a microreactor; and carrying out condensation reaction on the obtained intermediate and o-phenylenediamine dissolved in the composite solvent in series connection stirring kettles, and carrying out programmed cooling and crystal growing, separation, washing and drying to obtain the product. According to the method, side reaction is effectively inhibited, the product purity is high, the quality is stable, the production efficiency and the reaction yield are remarkably improved, and the microreactor and the reaction kettle are connected in series to realize whole-process continuous operation; by using the self-made efficient catalyst, the dosage of the catalyst is reduced, the reaction condition is mild, the reaction temperature is effectively reduced, the process time is shortened, meanwhile, the catalyst has no peculiar smell, the problem of irritating odor is avoided, and the operation environment is friendly.