144 results about "Dithiocarbamate" patented technology

The invention discloses a degradable express bag material and a preparation method thereof, and relates to the technical field of high polymer materials. The invention discloses a degradable express bag material. The composite material is prepared from the following raw materials in parts by weight: 40 to 50 parts of poly (butylene adipate-co-terephthalate), 20 to 30 parts of polycaprolactone, 5 to 8 parts of modified bamboo fiber, 2 to 4 parts of modified nano montmorillonite, 3 to 6 parts of tributyl citrate, 0.1 to 0.3 part of antioxidant 1076, 1 to 2 parts of iron dithiocarbamate master batch, 2 to 3 parts of maleic anhydride grafted poly (butylene adipate-co-terephthalate) and 0.3 to 0.6 part of zinc stearate. 0.1 to 0.3 part of baicalein; and 1 to 3 parts of chitosan-sorbitol composite coating liquid. According to the degradable express bag material, poly (butylene adipate-co-terephthalate) and polycaprolactone are used as main degradable raw materials, modified bamboo fibers and modified nano-montmorillonite are matched to enhance the mechanical property, an antioxidant 1076, baicalein and the like are added to guarantee the stability and functionality, temperature is accurately controlled in the preparation process, multi-step modification is adopted for optimizing component combination, and the degradable express bag material is prepared. The performance is improved through the composite coating, degradability is achieved, and good usability is achieved.

The invention relates to the technical field of functional board manufacturing, in particular to a damp-proof and wear-resistant composite board and a laminating process thereof. The composite material is prepared from 40-50 parts of dithiocar-bamate modified epoxy resin, 30-40 parts of nano silicon dioxide-carbon quantum dot modified polyurethane, 5-8 parts of a graphene-silane-metal organic framework compound, 2-4 parts of magnetic field oriented silicon carbide whiskers and 1-3 parts of self-repairing microcapsules. The modified epoxy resin is prepared from epoxy chloropropane and mercapto silane through a reaction, the graphene compound is embedded into the ZIF-8 nanoparticles, and the silicon carbide whiskers are directionally arranged through a 0.5-1T magnetic field during lamination; the plate is of a three-layer structure, covalent bonds are formed among layers through a silane coupling agent, and the plate has moisture-proof, wear-resistant and self-repairing functions. The composite material is low in water absorption rate, high in wear resistance frequency, high in microcrack repairing efficiency, high in interlayer bonding strength, capable of being stably used in high and low temperature environments, efficient in preparation process and suitable for the fields of high-end buildings, electronic equipment and the like, and the moisture-proof grade reaches IP67.

The invention discloses a dithiocarbamate monomer, a holographic recording medium, a preparation method and a related device, the structural general formula of the monomer is as shown in G1 and G2, R1 represents any one of hydrogen, halogen and C1-C4 alkyl, R3 represents any one of hydrogen, halogen and C1-C4 alkyl, A1 represents C1-C4 alkyl, A2 represents hydrogen or methyl, n is a positive integer, and n = 1-10. The dithiocarbamate monomer provided by the invention has high refractive index, and the holographic recording medium with high sensitivity, high diffraction efficiency and high refractive index modulation degree can be obtained by applying the dithiocarbamate monomer to preparation of the photopolymer holographic recording medium; holographic recording media can be used to prepare volume holographic gratings, holographic optical elements, and optical devices.

The invention relates to the technical field of sewage treatment in environmental protection, in particular to a high-valence metal cation composite remover and a use method of the high-valence metal cation composite remover. The polyhydroxy compound, the polycarboxyl compound and the polyamido compound are one or more than two of dithiomethyl carbamate, dithioethyl carbamate, dithiopiperazine dicarboxylate, trithiocyanate, hyperbranched vinylamine dithiocarbamate and dodecyl sulfonate, and the polyhydroxy compound, the polycarboxyl compound and the polyamido compound are one or more than two of dithiomethyl carbamate, dithioethyl carbamate, dithiopiperazine dicarboxylate, trithiocyanate, hyperbranched vinylamine dithiocarbamate and dodecyl sulfonate; the inorganic matter is one or more than two of silicate, phosphate and carbonate. According to the method, after the ammonia water is added, the composite removing agent is added for reaction and precipitation, the method has the advantages that the technological process is simple, the agent adding amount is small, the removal rate of high-valence metal cations reaches 99.9% or above, the operation cost is low, the pH value in the process is low, ammonia volatilization waste is inhibited and controlled, and the problems of safety and environmental protection are solved, and the method is suitable for industrial production.

The application discloses an automatic control method for oxidation flocculation parameters in mancozeb wastewater treatment, and belongs to the technical field of industrial wastewater treatment and automatic control. In view of the problem that the existing process relies on manual experience and the oxidation and flocculation stages are improperly connected, the multifunctional modified material containing dithiocarbamate salt groups, quinone groups and pre-complexed manganese and zinc ions is prepared first; the material and hydrogen peroxide are synchronously added in the acid oxidation stage, and the control system monitors the redox potential change rate in real time; when the redox potential reaches the preset threshold value and the characteristic change point with the first derivative of zero or the change from positive to negative appears and is maintained for the preset maintenance time, the system is automatically adjusted to be alkaline, the modified material triggers the net capture and chelation crosslinking reaction, and finally solid-liquid separation is carried out; the polymer skeleton is protected from indiscriminate attack of free radicals, the problem of drug antagonism is overcome, and the stable and up-to-standard effluent quality is realized.

Bicycle chain lubricant comprising base oil, a tackifier, and an anti-wear additive being either zinc dialkyl dithiophosphates (ZnDTP), molybdenum dithiocarbamates (MoDTC), or a mixture of both. The b

The invention discloses a method and a system for adding a 3N electrolytic manganese metal additive. The method comprises the steps that S1, a manganese sulfate neutral solution is prepared, after manganese carbonate ore powder is subjected to acid dissolution, sodium dimethyl dithiocarbamate and a barium sulfide purifying agent are added to conduct impurity removal, purification and acid collection on the manganese sulfate solution, then air is introduced to remove iron, the manganese sulfate solution obtained after filter pressing is neutralized with ammonia water, the pH value of the solution is adjusted, and the qualified manganese sulfate electrolyte is prepared. According to the 3N electrolytic manganese metal additive adding method and system, an ammonium sulfite adding method is changed from adding in a manganese sulfate neutral liquid tank to dropwise adding an ammonium sulfite aqueous solution at a liquid inlet port of an electrolytic bath, and the concentration and the liquid inlet speed of the ammonium sulfite aqueous solution are controlled, so that the content of ammonium sulfite in the electrolytic bath is stable, and the condition of the electrolytic bath is stable; the addition amount of the additive is reduced, introduction of impurities is avoided, and meanwhile, oxidation-reduction reaction caused by too long retention time of ammonium sulfite in the liquid is reduced.

This invention belongs to the field of mineral flotation technology, and discloses a flotation collector for non-ferrous metal sulfide ores, its preparation method, and its application. The collector uses O,O-dialkyldithiophosphate as a starting material, and reacts sequentially with a halocarboxylic acid ester, hydrazine hydrate, potassium hydroxide, and carbon disulfide in anhydrous ethanol in a three-step reaction to obtain the target product, O,O-dialkyldithiophosphate hydrazide-N′-dithiocarbamate potassium. Its molecular structure simultaneously contains three active groups: a dithiophosphate group, an hydrazide group, and a dithiocarbamate group. This invention achieves efficient process connection and smooth transition by optimizing the material ratio, temperature, and time of each reaction step, and has advantages such as mild reaction conditions, simple operation, few side reactions, high yield, and stable product. The prepared collector exhibits excellent collecting performance and good selectivity for non-ferrous metal sulfide ores such as chalcopyrite, and is suitable for widespread application in sulfide ore flotation processes.

The invention relates to the field of lubrication of ball screws, in particular to long-life creep-resistant lubricating grease for a high-precision ball screw, which comprises the following components in parts by weight: 65 parts of polyolefin, 5-10 parts of pentaerythritol ester, 5-10 parts of isocyanate, 2-5 parts of amine chain extender, 5 parts of PTFE (polytetrafluoroethylene), 1.0-1.5 parts of diphenylamine, 0.1-0.5 part of 2, 4-diphenyl-1, 3-pentanediol monoisobutyrate, 0.1-0.5 part of antioxidant, 0.1-0.5 part of antioxidant and 0.1-0.5 part of lubricant. The composite material is prepared from the following components in parts by weight: 0.5 to 1 part of 2, 6-butylated hydroxytoluene, 1.5 to 2 parts of molybdenum isocaprylate, 0.5 to 1 part of molybdenum bis (2-ethylhexyl) dithiocarbamate, 1 to 2 parts of zinc dialkyl dithiophosphate, 3 parts of calcium petroleum sulfonate, 1 to 1.5 parts of polyisobutene, 0.2 to 0.5 part of benzotriazole and 0.1 to 0.3 part of polymethacrylate. The isocyanate comprises HDI and IPDI, and the amine chain extender comprises TETA and TEPA. According to the invention, isocyanate and the amine chain extender react to form a polyurea macromolecular chain, and a high-energy hydrogen bond network is formed, so that the lubricating grease has relatively high creep resistance; the anti-creep performance is further enhanced through cooperation with the PTFE particles; meanwhile, through cooperation with diphenylamine, the oxidation resistance is promoted, the consumption is reduced, and the service life of the lubricating grease is longer.

A synthetic polyisoprene latex emulsion has pre-vulcanization composition and post vulcanization composition. The pre-vulcanization composition comprises insoluble amorphous sulfur extracted with zinc dithiocarbamate catalyst at 20° C. to form sulfur chain and transported to interior of synthetic polyisoprene particle forming physical attachment of sulfur to active sites. The degree of pre-vulcanization is verified by expansion of cast and dried film of latex in toluene in 20 minutes by means of a swelling index test. The latex emulsion is vulcanized at 90° C. to 120° C. for 3 to 5 minutes. Post-vulcanization composition with accelerators crosslink between synthetic polyisoprene particles, uniformly curing both in the inter-particle and intra-particle regions to produce high cross link density, uniform distribution of double bonds with zinc segregation at the boundaries of original particles. The condom exhibits high tensile strength, tensile modulus, elongation with excellent tear strength releasing below 10 ppb of nitrosamines.

The invention discloses an optimized synthesis method of bis (pentamethylene) thiuram tetrasulfide, which comprises the following steps: adding sulfur and piperidine into a reaction system in batches by utilizing the solubility difference of sulfur in carbon disulfide and water, so that condensation reaction is carried out step by step, the conversion rate of sulfur is increased, and the reaction system is controlled to keep constant temperature; and slowly dropwise adding hydrogen peroxide to carry out oxidation reaction to obtain the rubber vulcanization accelerator DPTT. According to the method, the condensation reaction process is split, so that the residual quantity of the intermediate product piperidine dithiocarbamate (PDC) and free sulfur is greatly reduced, and the content of bis (pentamethylene) thiuram tetrasulfide and the content of bis (pentamethylene) thiuram hexasulfide (DPTH) in the product are relatively stable. The total yield is stabilized at 96% or above, the initial melting point is stabilized at 112-114 DEG C, the PDC in the mother liquor is less than or equal to 6%, the free sulfur is less than or equal to 3%, the COD in the mother liquor is less than or equal to 3000 mg / L, the production operation is convenient and efficient, and the method has important industrial application value.

This invention proposes a lubricating oil composition for a four-stroke engine specifically designed for unmanned aerial vehicles (UAVs) and its preparation method. The lubricating oil composition for a four-stroke engine of this invention comprises the following components: (A) a nitrogen-containing organoboron compound; (B) an alkyl diphenylamine; (C) polyisobutylene succinimide; (D) sulfonates and / or sulfurized alkylphenol salts; (E) zinc dialkyl dithiophosphate; (F) dialkyl dithiocarbamate; (G) polymethyl methacrylate; and (H) a base oil in a major amount. The structure of the nitrogen-containing organoboron compound is shown in formula (I) and / or formula (II), with the definitions of each group provided in the specification. The lubricating oil composition for a four-stroke UAV engine of this invention exhibits excellent extreme pressure anti-wear, anti-oxidation, and detergency properties, effectively suppressing the increased wear caused by the high power-to-weight ratio and harsh lubrication conditions of four-stroke UAV engines.

The application discloses a hydrogen fuel engine oil composite additive composition, which comprises 3.0-5.0% high-alkali-value magnesium sulfonate, 12.0-20.0% low-alkali-value calcium sulfonate, 3.0-4.0% high-alkali-value calcium sulfide alkyl phenol, 2.0-5.0% amine type antioxidant, 2.0-5.0% phenol type antioxidant, 2.0-5.0% alpha-naphthylamine, 1.5-3.0% dibutyl dithiocarbamic acid ester, 1.5-3.0% anti-wear agent, 0.2-0.5% fatty amide, and the rest is ashless dispersant. The application further discloses a hydrogen fuel engine oil composition, which comprises 14.4-15.5% composite additive composition, 7.0-9.0% tackifier, 0.2-0.5% pour point depressant, and the rest is base oil. The composite additive improves the demulsification performance of the hydrogen fuel engine oil under high-temperature and high-pressure conditions, and further improves the water separation property and other comprehensive use performances of the oil product.

A grease composition includes a base oil, a thickener, and an extreme pressure additive. The base oil contains trimellitate ester and poly-α-olefin. A proportion of the trimellitate ester to a total amount of the trimellitate ester and the poly-α-olefin is 10.0 mass % or more and 60.0 mass % or less. The thickener contains lithium 12-hydroxystearate and lithium stearate. A proportion of the lithium 12-hydroxystearate to a total amount of the lithium 12-hydroxystearate and the lithium stearate is 5.0 mass % or more and 95.0 mass % or less. The extreme pressure additive contains molybdenum dialkyl dithiocarbamate. A proportion of the molybdenum dialkyl dithiocarbamate to a total amount of the trimellitate ester, the poly-a-olefin, the lithium 12-hydroxystearate, the lithium stearate, and the molybdenum dialkyl dithiocarbamate is 0.6 mass % or more and 16.0 mass % or less.

The application discloses a heavy metal chelating agent and a preparation method thereof. The heavy metal chelating agent is obtained by controlling the synthesis of melamine formaldehyde resin prepolymer and introducing a dithiocarbamate salt group with a chelating function into the structure of the melamine formaldehyde resin prepolymer. The heavy metal chelating agent has the characteristics of high efficiency and stability, high heavy metal removal rate, fast settling speed of chelation products, low leaching, and low cost, and is suitable for industrialized treatment of heavy metal pollution in fly ash and industrial wastewater.

A method for producing a fluoropolymer by solution polymerization or dispersion polymerization, the method including: in the presence of an initiator, a chain transfer agent, and a solvent, (i) homopolymerizing tetrafluoroethylene; or (ii) randomly copolymerizing tetrafluoroethylene and at least one of a monomer represented by the following formula (1) or a monomer represented by the following formula (2). The chain transfer agent includes at least one selected from dithioester compounds, dithiocarbamate compounds, trithiocarbonate compounds and xanthate compounds. The fluoropolymer contains 50 to 100 mol % of a polymerized unit based on the tetrafluoroethylene. The formula (1): CF2═CR1R2 wherein R1 and R2 are as defined herein, the formula (2): CH2═CR3R4 wherein R3 and R4 are as defined herein.

The invention discloses a complexing inhibitor for inhibiting redissolution of heavy metal sulfide as well as a preparation method and application of the complexing inhibitor. The complexing inhibitor is prepared by compounding the following three components: a component A which is a metal salt, a component B which is an organic sulfur medicament and a component C which is an organic non-sulfur medicament, wherein the mass ratio of the component A to the component B to the component C is (1-2): (1-3): (2-6); the component A is selected from dithiocarbamate, and the component B is selected from at least one of dithiocarbamate, mercaptobenzothiazole or sodium dimethyl dithiocarbamate; and the component C is selected from at least one of chitosan, polyethyleneimine or 1-hydroxyethylidene-1, 1-diphosphonic acid. The inhibitor is especially suitable for preventing excessive sulfur ions from complexing and dissolving precipitated heavy metal sulfide in industrial wastewater treatment, and effectively controlling the concentration of heavy metal ions to rise.

The invention belongs to the technical field of labor protection articles, and particularly relates to an environment-friendly butyronitrile glove and a preparation method thereof.The environment-friendly butyronitrile glove comprises a glove core, an environment-friendly butyronitrile rubber layer is fixed to the outer surface of the glove core in a gum dipping mode after the glove core is soaked in pretreatment liquid, and the environment-friendly butyronitrile rubber layer contains carboxyl butyronitrile latex; the environment-friendly butyronitrile rubber material is prepared by firstly pretreating carboxyl butyronitrile rubber latex and then mixing the pretreated carboxyl butyronitrile rubber latex with sodium dodecyl benzene sulfonate, a 5% potassium hydroxide solution, a 50% zinc oxide dispersion liquid, a 50% sulfur dispersion liquid, a 50% zinc dimethyldithiocarbamate dispersion liquid, a 50% titanium dioxide dispersion liquid, color paste and an alkali swelling type thickening agent. According to the invention, triple synergy of standard environmental protection, stable performance and controllable cost is realized, the industrial problem that protection performance, environmental benefits and economical efficiency are difficult to consider in the prior art is solved, and the dual requirements of modern environmental protection and use experience are met.

Some of the resin compositions are ultraviolet light or thermally curable, while others are ultraviolet light curable. One example of the ultraviolet light or thermally curable resin composition consists of a predetermined mass ratio of a (meth)acrylate cyclosiloxane monomer and a non-siloxane (meth)acrylate based monomer ranging from about >0:<100 to about 80:20; from 0 mass % to about 10 mass %, based on a total solids content of the resin composition, of an initiator selected from the group consisting of an azo-initiator, an acetophenone, a phosphine oxide, a brominated aromatic acrylate, and a dithiocarbamate; a surface additive; and a solvent.

Provided is a chloroprene polymer latex composition with which a dip-molded article having excellent flexibility and excellent tensile strength at break can be obtained. According to the present invention, provided is a chloroprene polymer latex composition containing a chloroprene polymer latex (A), a metal oxide (B), a vulcanization accelerator (C), sulfur (D), and an aromatic heterocyclic compound (E), the chloroprene polymer rubber obtained by freeze-drying the chloroprene polymer latex (A) having a toluene-insoluble component of 50-95% by mass, the chloroprene polymer latex composition contains 0.3-15.0 parts by mass of the metal oxide (B), 0.02-1.50 parts by mass of the vulcanization accelerator (C), 0.01-0.75 parts by mass of the sulfur (D), and 0.1-10.0 parts by mass of the heteroaromatic compound (E) per 100 parts by mass of the solid content of the chloroprene polymer latex (A), and the content of the metal oxide (B), the vulcanization accelerator (C), the sulfur (D), and the heteroaromatic compound (E) is 100 parts by mass of the solid content of the chloroprene polymer latex (A). The vulcanization accelerator (C) contains at least one of thiuram-based, dithiocarbamate-based, thiourea-based, guanidine-based, xanthate-based, and thiazole-based vulcanization accelerators, and the heteroaromatic compound (E) is represented by chemical formula (1).

The invention discloses a dithiocarbamate nickel (II) complex as well as a preparation method and application thereof, the chemical formula of the nickel (II) complex is [NiIILCl], and L is (E)-2-(phenyl (pyridine-2-yl) methylene) hydrazino methyl dithioformate. The nickel (II) complex is mild in synthesis condition and high in target yield. In-vitro MTT activity evaluation proves that the introduction of copper ions has a synergistic effect on the anticancer activity of the nickel (II) complex, so that the activity of the nickel (II) complex is improved from a micromole level to a nanomole level, and the amplification is as high as 200 times or more. Cell scratch experiments prove that the nickel (II) complex and copper (II) ions are combined for use, so that the migration resistance is achieved. A nickel (II) complex and copper ion combination strategy provided by the invention not only has a direct killing effect on cancer cells, but also can effectively inhibit the migration ability of the cancer cells, and shows huge application potential in the field of cancer treatment.

The invention belongs to the technical field of lubricating materials and particularly relates to wide-temperature-range lubricating grease for a helicopter transmission system as well as a preparation method and application of the wide-temperature-range lubricating grease. The wide-temperature-range lubricating grease for the helicopter transmission system comprises the following components: base oil, a thickening agent, a tribological property improver, an antioxidant, an adhesive and an antirust agent, the tribological performance improver is prepared from oxymolybdenum thiodibutyl dithiocarbamate, antimony dibutyl dithiocarbamate, tricresyl phosphate and bismuth sulfide according to the mass ratio of (3 to 5) to 1 to (1 to 3) to (0.1 to 1.5). The wide-temperature-range lubricating grease for the helicopter transmission system, provided by the invention, has outstanding high-temperature oxidation resistance, excellent extreme-pressure wear resistance and high-temperature performance and excellent low-temperature starting and operating torque, and can meet the use requirements of a lubricating grease product for the helicopter transmission system on wide temperature range and high load.

The application provides application of n-methyl-n-pentyl thiourea as a collector in a sulfur-oxygen mixed copper-cobalt ore and a synchronous flotation method, and relates to the technical field of flotation. In view of problems of the traditional sulfur-then-oxygen process, such as a complicated process, a complex process, and influence of changes of oxidation and sulfidation rates on the flotation effect of the sulfidized copper-cobalt ore, the application provides a new flotation process and reagent, does not need to use a sulfidation agent for sulfidation, simultaneously floats and sulfidizes and oxidizes the copper-cobalt ore, and simultaneously floats the oxidized and sulfidized copper-cobalt ore by using an activator sodium dimethyl dithiocarbamate and a chelate collector n-methyl-n-pentyl thiourea. The flotation process of the application is simple, efficient, clean and efficient, and provides a new method, a new process and a new way for the flotation of the complex sulfur-oxygen mixed copper-cobalt ore.

The application discloses a segmented leaching and adsorption reinforced silver recovery system and method, and belongs to the technical field of metallurgy. The system comprises two pre-leaching tanks, two silver adsorption tanks and at least four gold adsorption tanks connected in series, and the leaching tanks are connected in series. The silver adsorption tanks are filled with modified silver special adsorption carbon, and the gold adsorption tanks are filled with gold active carbon. The last gold adsorption tank is connected with the feeding end of a post-leaching thickener, the overflow supernatant of the post-leaching thickener is connected with the feeding end of a precipitation tank, and the discharging end of the precipitation tank is connected with the pre-leaching tank through a cyanide-resistant centrifugal pump. The system further comprises air lifters respectively inserted into the second silver adsorption tank and the last gold adsorption tank, and the air lifters are sequentially connected with a linear vibrating screen, a silver carbon desorption column or a gold carbon desorption column and an electrodeposition tank. The modified silver special adsorption carbon is loaded with a dithiocarbamate salt group on the surface. The system solves the problems of low silver recovery rate, long carbon extraction period, high reagent consumption and gold-silver adsorption competition in the existing whole mud cyanidation carbon pulp process.

The invention discloses a combined reagent for mixed flotation of copper-nickel sulfide ores and application, and belongs to the technical field of mineral flotation reagents. The combined medicament is composed of a component 1 (amine compound) and a component 2 (composite oil phase) which are independently subpackaged, and the component 2 is prepared by compounding sulfur-nitrogen ester, 2 # oil, N, N-dialkyl dithiocarbamate and a nonionic surfactant. Through step-by-step addition of the two components and synergistic compounding of the interior of the component 2, the agent has high collecting performance and good foaming performance, and the recovery rate of pentlandite and chalcopyrite is remarkably increased; meanwhile, the problems that a conventional medicament is easy to crystallize at low temperature and poor in flowability are effectively solved, and the medicament system is simple and low in cost. The method is particularly suitable for bulk flotation of the copper-nickel sulfide ore and has a wide industrial application prospect.

METHOD FOR SEPARING RARE EARTH ELEMENTS IN A MIXTURE IN AQUEOUS SOLUTION The invention relates to a method for separating two elements E1 and E2, selected from rare earth elements, in a mixture in aqueous solution SA. The method uses at least one dithiocarbamate salt. (no figures)

This invention provides a Fenton oxidation reaction promoter and a method for promoting the Fenton oxidation reaction. The promoter, by weight, comprises the following components in parts: 10-50 parts of a metal salt, 5-35 parts of a reducing agent, and 0-20 parts of an auxiliary agent. The amount of metal in the metal salt is not less than the amount of reducing agent, and the metal salt is selected from at least one of zinc or copper salts. The reducing agent is selected from at least one of sodium sulfide, sodium hydrosulfide, hydrogen sulfide, potassium sulfide, and potassium hydrosulfide. The auxiliary agent is selected from at least one of xanthic acid derivatives and dithiocarbamate derivatives. The Fenton oxidation reaction promoter is dissolved or suspended in water and added to the Fenton oxidation reaction process. It can promote the reduction rate of ferric iron, improve the Fenton oxidation effect, reduce the amount of iron added in the Fenton reaction, and thus reduce the yield of iron sludge. This promoter has the characteristics of low dosage, good effect, and simple and convenient use.

The invention discloses a preparation method of sulfoalkyl (methyl) acrylate, which is characterized in that (methyl) acrylic acid and hydroxyalkyl sulfonic acid are used as raw materials, an acidic resin catalyst is adopted, and the sulfoalkyl (methyl) acrylate is prepared by reaction in the presence of a solvent and a compound polymerization inhibitor, the compound polymerization inhibitor is a combination of a phenolic compound and at least one of the following compounds (A)-(D): (A) a quinone compound; (B) a nitroxide radical compound; (C) an inorganic salt compound; and (D) copper N, N-di-n-butyl dithiocarbamate. By using the method, the polymerization side reaction in the reaction process can be effectively inhibited, and the method has the advantages of short reaction time, simple post-treatment and low content of the hydroxyalkyl sulfonic acid dimer in the product.

This invention relates to the field of mineral processing flotation reagents, specifically disclosing a high-efficiency collector for the flotation of sphalerite and its preparation method. The high-efficiency collector provided by this invention achieves synergistic enhancement of the functions of each component by compounding isopropyl xanthate, dialkyl dithiocarbamate, and mercaptoacetate, and introducing a designed and synthesized polymeric synergist. The three basic collector components together constitute a dense and stable primary hydrophobic adsorption layer. The introduced synergist, on the one hand, enhances the adsorption strength and selectivity on the surface of sphalerite through multiple functional groups; on the other hand, its grafted hydrophilic polymer chains can form steric hindrance at the mineral-water interface and regulate local hydrophilicity and hydrophobicity, thereby further optimizing the hydrophobic state of the mineral surface and inhibiting gangue inclusions. The composite reagent provided by this invention improves the recovery rate of useful minerals while ensuring concentrate quality.

The invention provides a rare-earth slow-release fertilizer as well as a preparation method and application thereof. The rare-earth slow-release fertilizer comprises rare-earth slow-release particles and a basic fertilizer, the rare earth sustained-release particle comprises an inner core formed by rare earth ions and a chelating agent, and a coating layer coating the inner core, the chelating agent comprises unsubstituted and / or alkyl substituted dithiocarbamate; the basic fertilizer comprises any one or a combination of at least two of nitrogenous fertilizer, phosphatic fertilizer or potash fertilizer. The rare earth slow-release fertilizer provided by the invention realizes gradient release of rare earth ions, has slow-release stability in a wide pH range, reduces soil rare earth loss, improves the bioavailability of the rare earth ions, and reduces the risk of environmental pollution.