164 results about "Chloroacetic acid" patented technology

The invention discloses an anti-ultraviolet spinning yarn and a preparation method thereof, and relates to the technical field of spinning yarns. When the anti-ultraviolet spinning yarn is prepared, 2, 4, 6-tri (4-hydroxyphenyl) boroxane and methylphenyl phosphonium chloride are subjected to a reaction, and a phosphorus-boron composite flame retardant is prepared; the preparation method comprises the following steps: polymerizing indole and 5-(aminomethyl) indole to coat the surface of nano titanium dioxide to prepare pre-modified nano titanium dioxide; the pre-modified nano titanium dioxide and (3-acryloyloxypropyl) tri (trimethylsiloxy) silane are subjected to a reaction, and modified nano titanium dioxide is prepared; mixing poly (pentamethylene diamine adipate), the modified nano titanium dioxide and the phosphorus-boron composite flame retardant, and performing melt spinning to obtain polyamide fibers; spinning polyamide fibers to obtain polyamide spun yarns; the polyamide spinning yarn is sequentially finished with the chloroacetic acid finishing liquid and the isoliquiritigenin finishing liquid, and the anti-ultraviolet spinning yarn is prepared. The anti-ultraviolet spinning yarn prepared by the invention has excellent anti-ultraviolet, flame-retardant and anti-static properties.

The invention provides nano cellulose as well as a preparation method and application thereof. The preparation method comprises the following steps: (1) carrying out heating reaction on a mixed solution containing a biomass material and a eutectic solvent, and filtering to obtain fibers; (2) mixing the fiber with a solvent, and performing ultrasonic treatment to form the nano cellulose; wherein the eutectic solvent comprises a hydrogen bond donor and a hydrogen bond acceptor, the hydrogen bond donor is selected from 2-aldehyde acetic acid and / or chloroacetic acid, and the hydrogen bond acceptor is selected from choline chloride. The preparation method provided by the invention can effectively reduce the cost and energy consumption for synthesizing the nano cellulose.

The present invention provides a method for efficiently producing a nucleic acid oligomer. Specifically, the present invention provides a method for producing a nucleic acid oligomer represented by Formula (2), the method including a step of reacting a nucleic acid oligomer represented by Formula (1) with a dichloroacetic acid solution having a molar ratio of formaldehyde to dichloroacetic acid (formaldehyde mol / dichloroacetic acid mol) of 90×10−6 or less:wherein symbols have the meanings given in the description;wherein symbols have the meanings given in the description.

The invention discloses a preparation method of 3-quinuclidinone hydrochloride, which comprises the following steps: carrying out temperature control reaction on 4-picolinic acid and chloroacetic acid under alkaline water conditions to obtain an aqueous solution of a compound a, and directly entering the next reaction without post-treatment after the reaction is finished; adding a reducing agent alkaline water system into the aqueous solution of the compound a, controlling the temperature to react, controlling the temperature to adjust the pH value to 5-5.5 after the reaction is finished, extracting with n-butyl alcohol, and drying to obtain an n-butyl alcohol solution of a compound b, and directly entering the next reaction step; wherein the reducing agent is one of sodium borohydride and potassium borohydride; dropwise adding thionyl chloride into an n-butyl alcohol solution of the compound b, controlling the temperature to react after dropwise adding is ended, and concentrating to remove the solvent and unreacted thionyl chloride after the reaction is ended, so as to obtain a compound c; carrying out Dieckmann condensation reaction on the compound c at controlled temperature under the condition of organic alkali by using toluene as a solvent, carrying out hydrochloric acid quenching reaction after the reaction is finished, and directly carrying out next-step reaction after extracting and removing impurities from a water phase containing a hydrochloride solution of a compound d by using toluene; and carrying out a decarboxylation reaction on the compound d in a hydrochloric acid aqueous solution at controlled temperature, after the reaction is finished, adjusting the pH value to 10-13, extracting, and salifying to obtain a target compound TM, namely 3-quinuclidinone hydrochloride. The preparation method of 3-quinuclidinone hydrochloride provided by the invention has the advantages of economical and easily available raw materials, mild reaction conditions, efficient reaction, simple operation and low cost, and is suitable for industrial application.

This invention provides a continuous method for preparing high-purity creatine monohydrate, comprising the following steps: a) adding chloroacetic acid aqueous solution dropwise to an aqueous methylamine solution, stirring at room temperature for 2 hours after the addition is complete; b) heating to 50-60°C and holding for 1 hour to remove most of the methylamine, then heating to 95°C to evaporate the methylamine aqueous solution for 1 hour; c) adding sodium hydroxide solution dropwise to the solution from step b) at 95°C, then heating to 105°C and concentrating under reduced pressure for 1.5 hours to approximately half the original volume, obtaining a creatine solution with a concentration of 30%-40%; d) cooling the solution from step c) to 40-60°C and adding a catalyst; e) drying to obtain pure creatine monohydrate. This invention reduces the methylamine equivalent, saving costs, and eliminates the need for purifying creatine for direct use in the next reaction; it can simultaneously lower the system reaction temperature and pH value to inhibit the formation of byproducts dicyandiamide and creatinine, and eliminates the need for debittering agents for purification and debittering, thus saving production costs.

The invention belongs to the technical field of glycine preparation, and particularly discloses a preparation method of glycine. The method comprises the following steps: controlling the reaction temperature, efficiently synthesizing ammonium chloroacetate from chloroacetic acid and liquid ammonia in a reactor, carrying out catalytic ammonolysis on the ammonium chloroacetate and ammonia gas in a reactor filled with a solid catalyst to realize continuity and reinforcement of the process, and carrying out alcohol precipitation crystallization, separation and purification to obtain glycine. The solid catalyst provided by the invention has the advantages of simple preparation, reproducibility, long service life, no metal pollution, easily available raw materials, controllable cost, long-acting cyclic utilization, high efficiency, simple recovery and the like; the method for preparing glycine by using the solid catalyst solves the problems of high consumption, high recovery cost, low production and purification efficiency and pollution caused by the traditional catalyst, and is a key technology for green and low-cost industrial production of glycine.

The utility model relates to a chloroacetic acid production device for processing glycine, which is characterized in that an interlayer is arranged in the outer wall of a chlorination kettle, the side end is connected with a liquid level meter a, and a discharge pipe is arranged on the lower surface; a radar liquid level instrument, a chlorine feeding pipe, an on-line component analyzer, an on-line thermometer, an on-line hydrometer, a condensation pipe, a catalyst filling pipe and an acetic acid feeding pipe are sequentially arranged on the upper surface, the lower end of the chlorine feeding pipe is connected with a gas distributor, and the condensation pipe is externally connected with a condenser; the catalyst filling pipe is externally connected with a catalyst metering tank; a liquid level meter b is connected to the side end of the kettle body, a discharging pipe is arranged on the lower surface of the kettle body, a water supplementing pipeline is connected to the right side of the upper surface of the kettle body, a liquid inlet pipe and an online moisture measuring device are arranged on the left side of the upper surface of the kettle body, and the liquid inlet pipe is communicated with the discharging pipe; the upper end of the stirrer is connected with a stirring motor, and the lower end is connected with a frame-type stirring paddle; the utility model has the advantages of reasonable structural design and good use effect.

The application provides a preparation method of a rare earth metal adsorption and separation resin and a resin extraction column. The preparation method comprises the following steps: adding an oil phase composed of styrene, divinylbenzene, a pore former and an initiator into an aqueous phase containing a dispersant and an inorganic salt to perform suspension polymerization, so as to obtain a white ball resin; performing phthalimide and hydrolysis on the white ball resin, so as to obtain a primary amine resin; performing reaction on the primary amine resin with chloroacetic acid and an alkaline medium, so as to perform carboxymethylation on part of the primary amine sites; and performing reaction on the obtained intermediate resin with phosphorous acid, formaldehyde and an acidic medium, so as to perform phosphonic acid methylation on the remaining part of the primary amine sites. The white ball resin is first subjected to amination, and then part of the carboxymethylation and part of the phosphonic acid methylation are sequentially performed, so that the carboxyl type chelation sites and the phosphonic acid type chelation sites are simultaneously reserved in the same resin bead, thereby being beneficial to improving the comprehensive adsorption performance and separation performance of the resin on the rare earth metal.

This invention discloses a rice straw-based liquid mulch film emulsion, its preparation method, and its application. The preparation method includes: treating pretreated rice straw with an alkaline solution in sodium hydroxide to obtain rice straw fibers and a silicon-containing black liquor; washing and bleaching the rice straw fibers to obtain bleached rice straw fibers; allowing the silicon-containing black liquor to stand, adjusting the pH value, and allowing it to stand again to obtain a silicon-containing dispersion; mixing and activating the bleached rice straw fibers with an alkaline alcohol solution, followed by etherification with chloroacetic acid to obtain carboxymethyl cellulose; mixing polyvinyl alcohol and carboxymethyl cellulose solutions, adding the silicon-containing dispersion under stirring, and then adding water to obtain the rice straw-based liquid mulch film emulsion. The rice straw-based liquid mulch film emulsion prepared by this invention can be used for soil covering in cultivated soils, exhibiting excellent film-forming strength, toughness, light-blocking properties, and soil cover adaptability. It has a wide range of raw material sources, a simple preparation process, and is suitable for large-scale promotion.

The utility model discloses a cleaning system for industrial glycine dirty materials by chloroacetic acid ammonolysis, which comprises a vibrating screening machine, a material dissolving tank, a clarifying tank and a crystallizing kettle which are sequentially connected through pipelines, the material dissolving tank is of a cylindrical structure, a stirring device is arranged in the material dissolving tank, a water inlet is arranged at the top of the material dissolving tank, a jacket is arranged on the outer side of the material dissolving tank, and the crystallizing kettle is arranged in the jacket. A steam inlet and a steam outlet are formed in the jacket, a liquid level transmitter and a temperature transmitter are arranged in the material melting tank, the bottom of the vibrating screen machine is connected with a feeding port of the material melting tank, a discharging port in the bottom of the material melting tank is connected with a feeding port in the top of the clarifying tank, and a filter is arranged on a connecting pipeline of the clarifying tank and the crystallization kettle. According to the method, different types of glycine dirty materials can be effectively cleaned, impurities in the different types of glycine dirty materials can be effectively removed, a pure glycine product is obtained, and recycling of resources is achieved.

The invention belongs to the technical field of acyclic compounds, and particularly relates to a method for preparing chloroacetic acid by hydrogenation reduction of dichloroacetic acid, which comprises the following steps: A1, adding a chlorination liquid containing dichloroacetic acid into a raw material storage tank, mixing with hydrogen, and heating to obtain a mixed material; a2, conveying the mixed material into a hydrogenation reactor loaded with a composite metal modified catalyst for reaction to obtain chloroacetic acid liquid and mixed gas; and A3, conveying the mixed gas to a stripping tower, condensing the mixed gas through a condenser to obtain hydrogen chloride gas and condensate, and conveying the condensate to the hydrogenation reactor again for recycling. According to the method disclosed by the invention, a byproduct, namely the chlorination liquid, generated in a chlorination reaction in a chloroacetic acid production process is used as a reaction raw material, dichloroacetic acid and trichloroacetic acid in the chlorination liquid can be effectively reduced into chloroacetic acid, and other substances in the chlorination liquid cannot be influenced.

The present invention provides a production method for purified dichloroacetic acid and an efficient production method for nucleic acid molecules using same. Specifically, the present invention provides: a production method for purified dichloroacetic acid in which the molar ratio of formaldehyde to dichloroacetic acid is 81×10-5 or lower and the molar ratio of dichloroacetic anhydride to dichloroacetic acid is 20×10-5 or lower, wherein dichloroacetic acid having a formaldehyde and / or dichloroacetic anhydride content higher than the aforementioned ratios is brought into contact with at least one compound having a lower boiling point than dichloroacetic acid selected from the group consisting of aliphatic alcohols, aliphatic amines, and water, and a fraction including an aprotic inert solvent having a boiling point lower than that of dichloroacetic acid is distilled from the produced mixed liquid in the presence of the solvent; and a production method for nucleic acid molecules in which the purified dichloroacetic acid is used as a deprotection agent.

The invention belongs to the technical field of environmental engineering, and particularly relates to a rapid prediction method for trichloroacetic acid generation potential in a water disinfection process. The rapid prediction method for the trichloroacetic acid generation potential in the water disinfection process comprises the following steps: constructing a training set and a test set which respectively and independently comprise a plurality of organic compounds and trichloroacetic acid generation potential values and key molecular characteristic parameters corresponding to each organic compound; an extreme gradient lifting machine learning algorithm is adopted to construct a trichloroacetic acid generation potential prediction model, and model precision verification is carried out; optimizing by adopting a Bayesian optimization algorithm to obtain a trichloroacetic acid generation potential optimal prediction model; and inputting the key molecular characteristic parameters of the target compound into the optimal prediction model to obtain the trichloroacetic acid generation potential value of the target compound. The rapid prediction method provided by the invention realizes rapid prediction of the TCAAFP value of the organic compound in the chlorine disinfection reaction, and has the advantages of convenient operation, low cost, strong stability and wide application range.

The invention discloses a high-wettability and strong-adhesion cross-linking enhanced dust fall material. The dust fall material comprises the following raw materials in parts by mass: 2-5 parts of pullulan, 2-5 parts of agarose, 5-15 parts of sodium hydroxide, 5-15 parts of chloroacetic acid, 5-15 parts of ethylene glycol diglycidyl ether, 3-11 parts of malic acid, 5-10 parts of a water-retaining agent, 5-10 parts of diluted hydrochloric acid and 1000-2500 parts of distilled water. The dust falling material has high wettability and strong adhesion, and can effectively settle coal dust in air; meanwhile, a coal dust consolidation layer formed after the dust falling material is sprayed is high in strength, reentrainment of dust can be effectively prevented, and the technical problems that the dust falling material is poor in dust falling effect, single in function and the like are solved.

The invention discloses a preparation method of a difluoromethyl reagent and application of the difluoromethyl reagent in synthesis of a nickel-catalyzed alkyl difluoromethyl compound. The preparation method of the difluoromethyl reagent comprises the following steps: in an inert gas atmosphere, adding potassium iodide, cuprous iodide and a water-containing dimethylformamide solution into a reaction container, heating, dropwise adding difluorochloroacetic acid of DMF (Dimethyl Formamide) into a reaction system, collecting difluoroiodomethane, and supplementing a 1-methyl-2-pyrrolidone NMP (N-Methyl Pyrrolidone) solution into the system. The invention provides a difluoromethyl reagent which is simple and convenient to operate, low in cost, high in yield, environment-friendly and beneficial to large-scale preparation and application of the reagent in synthesis of difluoromethyl substituted alkane compounds.

This invention belongs to the field of recycling and purification technology, specifically relating to a method for recovering the β isomer from a CME solution containing both β and α isomers. The method includes the following steps: concentrating the CME solution containing both β and α isomers and dissolving it in methanol with trichloroacetic acid to form a salt, followed by cooling and crystallization and filtration to obtain the trichloroacetic acid salt of the CME β isomer; then, ionizing the trichloroacetic acid salt of the CME β isomer in methanol with ammonia to obtain the CME β isomer. By reacting trichloroacetic acid with the α and β isomers of CME to form a salt, the different solubilities of the trichloroacetic acid salts of the α and β isomers are utilized to separate the trichloroacetic acid salt of the CME β isomer, and then ionizing the trichloroacetic acid salt of the CME β isomer with ammonia, the CME β isomer is recovered.

The invention provides a bagasse nanocellulose-based antibacterial composite film as well as a preparation method and application thereof, and belongs to the technical field of food packaging materials. The preparation method comprises the following steps: sequentially carrying out alkali treatment, bleaching treatment and acid treatment on bagasse to obtain bagasse microcrystalline cellulose; the preparation method comprises the following steps: reacting bagasse microcrystalline cellulose, absolute ethyl alcohol and chloroacetic acid, and shearing after the reaction is finished, so as to obtain chloroacetic acid grafted and modified bagasse nano cellulose; dispersing konjac glucomannan in water to obtain a konjac glucomannan dispersion liquid, then adding citrus essential oil and bagasse nanocellulose into the konjac glucomannan dispersion liquid to carry out a secondary reaction, adding a plasticizer after the reaction is finished, and adjusting the pH value with citric acid to obtain a film forming liquid; and drying the film forming liquid to obtain the bagasse nano cellulose based antibacterial composite film. The antibacterial composite film prepared by the invention has excellent tensile strength, water vapor permeability and antibacterial activity, and can be used for monitoring the freshness of high-protein food.

The utility model discloses a system for recycling chloroacetic acid by dechlorinating dichloroacetic acid through photocatalysis, which relates to the technical field of chloroacetic acid synthesis equipment and comprises a collecting tank I used for collecting mother liquor containing dichloroacetic acid during preparation of chloroacetic acid, and the collecting tank I is sequentially connected with a plurality of stages of condensers and a filter I through pipelines. A filtrate outlet I of the filter I is sequentially connected with a storage tank, a photocatalytic reaction kettle, a plurality of stages of condensers and a filter II; a filtrate outlet II of the filter II is connected with the storage tank through a reflux pipeline; stirring mechanisms are arranged in the collecting tank I and the photocatalytic reaction kettle, an ultraviolet visible light lamp is mounted in the photocatalytic reaction kettle, a material inlet of the photocatalytic reaction kettle is connected with a mother liquor supply pipeline, a water supply pipeline, a catalyst supply pipeline and a hydrogen supply pipeline, and the collecting tank I is connected with a nitrogen pipeline. The yield of chloroacetic acid prepared by an acetic anhydride catalysis method is improved, the generation of waste liquid is reduced, and the treatment cost of wastewater is reduced.

This invention relates to the field of dichloroacetic acid preparation technology, specifically a method for preparing high-purity dichloroacetic acid. The method uses anhydrous dichloroacetic acid alkyl ester or anhydrous dichloroacetyl chloride as a single raw material. The method includes: adding deionized water to a corrosion-resistant reactor, starting stirring and cooling to 10-30°C, adding the single raw material and an acidic catalyst, reacting at 40-80°C for 1-8 hours, and then refining through multi-stage separation to obtain high-purity dichloroacetic acid. The anhydrous dichloroacetic acid alkyl ester is selected from methyl dichloroacetate, ethyl dichloroacetate, propyl dichloroacetate, or isopropyl dichloroacetate. The acidic catalyst is a ZrO₂-TiO₂ supported acid solid catalyst or a complex liquid organic acid catalyst.

The invention relates to a method for improving antioxidant activity of pine pollen polysaccharide by utilizing bifidobacterium fermentation, which comprises the following steps: S1, adding bifidobacterium liquid into pine pollen for fermentation to obtain a fermentation product; s2, adjusting the pH value of the fermentation product in the step S1 to be acidic, and adding protease for enzymolysis to obtain an enzymolysis product; s3, carrying out flash extraction on the enzymolysis product obtained in the step S2, and centrifuging to take supernate, so as to obtain a pollen pini crude polysaccharide extracting solution; and S4, adding a trichloroacetic acid solution into the pollen pini crude polysaccharide extracting solution obtained in the step S3, and dialyzing to obtain the pollen pini polysaccharide with improved antioxidant activity. Compared with the prior art, the pine pollen polysaccharide obtained through fermentation of bifidobacteria can obviously improve the antioxidant activity, improve the development and utilization value of pine pollen and improve the application and market competitiveness of the pine pollen polysaccharide in multiple fields compared with the pine pollen polysaccharide obtained through unfermented pine pollen polysaccharide.

The application relates to the technical field of biological detection, and particularly relates to a sample processing liquid and application thereof in ELISA detection of milk and milk products. The sample processing liquid comprises the following components in percentage by weight: 2-3% of ethylenediaminetetraacetic acid disodium salt dihydrate; 0.075-0.125% of trichloroacetic acid; 10-30% of methanol; and the balance is ultrapure water; and the sample is milk and milk products. The sample processing liquid provided by the application can efficiently and conveniently reduce the matrix interference of milk and milk products in ELISA detection, so that the accuracy, precision and recovery rate of detection can be significantly improved.

The invention relates to the field of macromolecules, and discloses a method for refining polyetherketoneketone and a polyetherketoneketone refined product. The method comprises the following steps: (1) treating a polyetherketoneketone complex by adopting a pretreatment agent; (2) the polyether ketone ketone crude product and a mixed chain supporting solution are mixed and washed, a first product is obtained, the mixed chain supporting solution comprises a main chain supporting agent and a cosolvent, the main chain supporting agent comprises one or more selected from parachlorophenol, trifluoroacetic acid, difluoroacetic acid, dichloroacetic acid and chloroacetic acid, the cosolvent comprises one or more selected from N, N-dimethylformamide and dimethyl sulfoxide, and the main chain supporting agent comprises one or more selected from dichlorophenol, trifluoroacetic acid, difluoroacetic acid, dichloroacetic acid and chloroacetic acid. The solvent is one or more of water, N-methyl pyrrolidone and N-methyl formamide; (3) adding a mixed aqueous solution into the first product to remove at least part of metal ions to obtain a second product; and (4) washing the second product for multiple times by using an organic solvent, and washing and drying to obtain the refined polyether ketone ketone. The content of aluminum ions in the polyetherketoneketone prepared by the method is low.

The invention provides a method for simultaneously detecting dichloroacetic acid and trichloroacetic acid in urine, and belongs to the technical field of analysis detection and occupational health / environmental health. According to the method disclosed by the invention, a synergistic pretreatment strategy of acidic sample loading, WAX / reversed-phase mixed mode solid-phase extraction, water / low-proportion organic phase step-by-step leaching and ammonia-water-containing organic phase elution is adopted; a technical route of protein precipitation, acidification pH regulation, purification and enrichment by adopting WAX / reversed-phase mixed mode solid-phase extraction on a 96-well plate and stable isotope internal standard isotope dilution LC-MS / MS quantification is adopted, the method can effectively reduce the matrix effect and realize high-throughput analysis in a high-salinity urine matrix, the quantitation limits of DCEA and TCAA are not higher than 0.30 g / L and 0.20 g / L respectively, and the method has the advantages that the method is simple and convenient to operate, and the method is suitable for large-scale popularization and application. The method is suitable for biological monitoring and risk assessment of occupational and environmental low-level exposure crowds.

The invention relates to the technical field of food detection, discloses an efficient detection method for six sugar alcohol compounds in dairy products, and aims to solve the problems that in the prior art, dairy product protein precipitation and high-efficiency dissolution of strong-polarity sugar alcohol are difficult to consider at the same time, and toxic precipitants, high-temperature treatment or complex solid-phase extraction are often depended on. The problems of tedious operation, high equipment threshold and poor detection stability exist in the prior art, trichloroacetic acid with optimized concentration is used for constructing a water phase system, and dissolution of six sugar alcohols and preliminary precipitation of protein are synchronously realized; the high-protein matrix of the milk powder is supplemented with precise supplementary precipitation, and the liquid milk is simplified; a specific chromatographic column and gradient elution are combined, linear correlation is established by adopting an external standard method, synchronous detection of six sugar alcohols is completed, high-temperature and solid-phase extraction consumables are not needed, two matrixes of milk powder and liquid milk are adapted, the operation time is short, the detection recovery rate is high, the precision is excellent, the existing pain point is effectively solved, and the batch detection requirement of a conventional laboratory is met.

The invention relates to the technical field of unqualified product treatment equipment, in particular to an unqualified product chloroacetic acid waste dissolving tank and a working method.The unqualified product chloroacetic acid waste dissolving tank comprises a dissolving tank body, a stirring device and a temperature control device.The dissolving tank body is provided with a feeding port and a discharging port, and the stirring device comprises a stirring shaft sleeve, stirring blades and a motor; the temperature control device comprises a heating jacket arranged outside the dissolving tank body in a sleeving mode, a connecting pipeline communicated with a heat source is arranged on the heating jacket, the temperature control device further comprises a temperature sensor, the detection end of the temperature sensor is located in the dissolving tank body, and the temperature sensor is in signal connection with the heat source through a controller. According to the technical scheme, chloroacetic acid waste and a solvent are fully contacted and mixed through the stirring device, the dissolving speed is greatly increased, the temperature control device ensures that the temperature in the dissolving tank body is stabilized in a proper dissolving temperature range, and effective treatment and recycling of unqualified chloroacetic acid waste are achieved.

The invention relates to a quaternary ammonium salt collecting agent for reverse flotation of refractory hematite at room temperature and application of the quaternary ammonium salt collecting agent, the quaternary ammonium salt collecting agent is structurally a cationic compound with an ester group, n-caprylic alcohol and chloroacetic acid react to obtain octyl chloroacetate, and then the octyl chloroacetate reacts with tertiary amine. The molar ratio of n-caprylic alcohol to chloroacetic acid is 1: (1.05-1.15), the reaction temperature is 80-90 DEG C, and the reaction time is 7-9 hours; the molar ratio of the octyl chloroacetate to the tertiary amine compound is 1: (1.1-1.3), the reaction temperature is 70-90 DEG C, and the hematite room-temperature reverse flotation quaternary ammonium salt collecting agent is obtained by reacting in an acetonitrile solvent for 2-6 hours. The quaternary ammonium salt collecting agent with the ester group is independently applied to room-temperature reverse flotation of the refractory hematite.

An improved method of producing monochloroacetic acid (MCAA) is disclosed, which affords a colorless monochloroacetic acid product in any form that can be obtained by this method.

The utility model discloses a hydrogen chloride removal system suitable for a process of producing chloroacetic acid by an acetic acid method, and belongs to the technical field of glycine production. The hydrogen chloride removal system comprises a separation kettle, a condenser, a packing absorption tower and an acetyl chloride recovery tank, the separation kettle is connected with the chlorination reaction kettle, and the separation kettle is connected with the condenser; the condenser is connected with the separation kettle through a return pipe, a non-condensable gas outlet on the condenser is connected with the packing absorption tower through a non-condensable gas outlet pipe, and a vacuum pump is arranged on the non-condensable gas outlet pipe; the packing absorption tower is connected with an acetic acid inlet pipe, an upper gas phase outlet of the packing absorption tower is connected with a tail gas treatment system, and the packing absorption tower is connected with an acetyl chloride recovery tank through an acetyl chloride outlet pipe; the acetyl chloride recovery tank is connected with the chlorination reaction kettle through a recycling pipe and is also connected with the packing absorption tower through a circulating pipe. Acetyl chloride in a chloroacetic acid finished product is recovered and used for a chlorination process, so that the consumption of raw material acetic anhydride is reduced; and meanwhile, the loss amount of raw material liquid ammonia in the subsequent ammoniation process is reduced.

The invention belongs to the technical field of soil curing agents, and particularly relates to an anti-freeze-thaw sludge curing agent and a preparation method and application thereof. The sludge curing agent comprises the following raw materials in parts by mass: 40-60 parts of cement, 10-20 parts of an admixture, 10-20 parts of quicklime, 5-10 parts of gypsum, 5-8 parts of carboxylated porous resin, 0.5-0.8 part of a nonionic surfactant and 5-8 parts of activated carbon, and the carboxylated porous resin is of a three-dimensional network structure formed by condensation reaction of phenolated alkali lignin and dialdehyde. Meanwhile, porous resin microspheres are formed by utilizing a pore-foaming agent, and then the porous resin microspheres, chloroacetic acid and alkali are subjected to a reaction to prepare carboxylated porous resin microspheres. According to the non-ionic surface active agent disclosed by the invention, organic matters which are easy to migrate and free in the sludge are emulsified into micro-micelles, and the micro-micelles are adsorbed by the activated carbon, so that the micro-micelles are prevented from wrapping gel particles, hydration is hindered, a communicated pore network is prevented from being formed, and the freeze-thaw resistance of a sludge solidified body is improved. The inner surfaces of pores of carboxylated porous resin contain a large amount of phenolic hydroxyl groups and carboxyl groups, so that the migration activity of heavy metal ions is reduced.

This invention discloses a cross-linked carboxymethyl corn starch adsorbent, its preparation method, and its application. The method involves first mixing corn starch with 85%-95% ethanol (by mass) and stirring until homogeneous; adjusting the pH of the starch emulsion to 10-12, preheating at 50-60°C, adding 0.1%-0.15% epichlorohydrin (by dry starch weight), and continuously stirring for 1-2 hours; after cooling to room temperature, adding solid sodium hydroxide for alkalization, adding chloroacetic acid to the alkalized system, and reacting at 50-60°C for 2-4 hours; after the reaction, adjusting the pH of the reaction system to 6-7, filtering, washing, drying, and sieving to obtain the cross-linked carboxymethyl corn starch adsorbent. This invention overcomes the defects of poor structural stability and low adsorption capacity of unmodified starch. The resulting adsorbent is environmentally friendly, has excellent adsorption performance, and the preparation process is simple, controllable, and low-cost.