10 results about "MONOCHLOROACETIC ACID" patented technology

The present application relates to a kind of preparation method of trifluoromethyl pyrazole compound, belong to the technical field of organic synthesis.The specific method is: (1) trifluoroacetyl ethyl acetate is first with hydrazine hydrate cyclization reaction and generates compound of formula III;(2) under the catalysis of base, compound of formula III is reacted with difluoromethylation reagent and generates compound of formula II;(3) compound of formula II is reacted with methylating agent and obtains compound of formula I;The difluoromethylation reagent is difluoro-monochloromethane or sodium difluoro-monochloroacetate;The methylating agent is chloromethane, bromomethane, iodomethane, dimethyl sulfate or dimethyl carbonate.The present application is prepared by changing reaction route, and the higher-priced raw material methylhydrazine is replaced, and isomer impurity is no longer generated in the product prepared.Not only raw material cost is reduced, but also the purity of product is improved.

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 invention relates to a preparation method of fatty acid amide propyl betaine, and belongs to the technical field of surfactants. The preparation method provided by the invention comprises the following steps: S1, adding N, N-dimethyl propane diamine into an initial raw material, and carrying out heating reflux reaction to obtain fatty acid amide propyl dimethylamine; the initial raw materials comprise at least one of fatty acid and derivatives thereof; s2, adding water, monochloroacetic acid and a sodium hydroxide aqueous solution into fatty acid amide propyl dimethylamine, heating and carrying out quaternization reaction to obtain a crude product; s3, hydrolyzing the crude product under the conditions that the temperature is 70 to 100 DEG C and the pressure is 0.1 to 0.5 MPa, so as to obtain the fatty acid amide propyl betaine. According to the preparation method provided by the invention, other impurities do not need to be introduced for post-treatment, the prepared fatty acid amide propyl betaine can effectively hydrolyze residual monochloroacetic acid and dichloroacetic acid, by-products are reduced, the product safety is remarkably improved, and the fatty acid amide propyl betaine has a relatively high application value.

Topical formulations comprising peroxyacids prepared in situ from trichloroacetic acid, dichloroacetic acid, monochloroacetic acid or acetic acid and hydrogen peroxide are useful for promoting hair growth and for preventing hair loss.

The invention belongs to the technical field of wastewater treatment, and particularly relates to a modified chitosan-based material as well as a preparation method and application thereof. The preparation method of the modified chitosan-based material comprises the following steps: dropwise adding acid into a precursor aqueous solution, and carrying out protonation reaction to prepare a protonated chitosan solution; adding tripolyphosphate into the protonated chitosan solution, and carrying out a cross-linking reaction to prepare modified chitosan powder; the precursor aqueous solution is a chitosan aqueous suspension or a Schiff base chitosan solution; the acid is hydrochloric acid or monochloroacetic acid. And subsequently, adding water, sodium alginate and a cross-linking agent into the modified chitosan powder to prepare the modified chitosan hydrogel. The defects that an existing chitosan derivative is not developed in pore structure, not obvious in specific surface area and not rich in active sites are overcome, and the problems that when an existing chitosan-based uranium removal material is used for treating weak-acid uranium-containing wastewater, complexing strength is low, adsorption capacity is small, separation and recovery are difficult, and potential secondary pollution is caused are solved.

Manufacturing process for a high viscosity lithium carboxymethylcellulose, wherein the lithium carboxymethylcellulose has a 1% viscosity of > 25000 mPa·s, characterized in that this process comprises the following steps: Mixing a cellulose, an aqueous solution of a polar solvent, and a sodium hydroxide solution in an ethanol solution; filling with nitrogen gas to create an inert atmosphere after vacuuming to remove air; carrying out an alkalization reaction under the inert atmosphere; subjecting a reaction product to etherification under normal pressure to obtain crude CMC-Na; acidifying the crude CMC-Na to obtain CMC-H; and adding the prepared CMC-H to a lithium salt ethanol solution to carry out a substitution reaction to obtain high-viscosity lithium carboxymethylcellulose; The amounts of cellulose, aqueous solution of the polar solvent, sodium hydroxide solution, and ethanol solution added in the alkalization reaction are 3 to 10 parts, 2 to 15 parts, 1 to 8 parts, and 5 to 25 parts, respectively, based on parts by weight; the aqueous solution of the polar solvent contains 20% to 85% methanol or isopropanol; the volume concentration of the ethanol solution is 70% to 95%; and the concentration of the sodium hydroxide solution is 25% to 50%. Specific steps of the alkalization reaction are as follows: Place the raw materials in the specified weight parts into a reactor, vacuum-seal for the first time to -10 to -25 kPa, then fill with nitrogen to 3 to 10 kPa, vacuum-seal a second time to -25 to -80 kPa, refill with nitrogen to 3 to 10 kPa, carry out the alkalization reaction; maintain a nitrogen gas pressure of 3 to 10 kPa during the reaction, and the duration of the alkalization reaction is 30 minutes; Specific steps of the etherification reaction are as follows: Addition of a product of the alkalization reaction to a monochloroacetic acid-ethanol solution to carry out an etherification reaction under normal pressure; a mass concentration of the monochloroacetic acid in the monochloroacetic acid-ethanol solution is 45% to 65%, a concentration of the ethanol in the monochloroacetic acid-ethanol solution is ≥93%, an amount of monochloroacetic acid-ethanol solution added is 2 to 10 parts by weight, and a duration of the etherification reaction is 30 to 80 min; The specific steps of the acidification reaction are as follows: Adding the crude CMC-Na to a sulfuric acid solution to carry out the acidification reaction in a normal pressure system; the concentration of the sulfuric acid solution is 10% to 40%, and the duration of the acidification is 60 to 180 min; the pH of the substitution reaction is 6.5 to 10.0 and the duration of the substitution reaction is 30 to 120 min.

The invention belongs to the technical field of chemical analysis and detection, and particularly relates to a method for distinguishing fatty alcohol-polyoxyethylene ether carboxylic acid prepared by an oxidation method and fatty alcohol-polyoxyethylene ether carboxylic acid prepared by a carboxymethylation method. According to the principle, the fatty alcohol-polyoxyethylene ether carboxylic acid product prepared by using two methods has different residual impurities, and the content of monochloroacetic acid and chloride ion impurities is determined by using an ion chromatography so as to identify the fatty alcohol-polyoxyethylene ether carboxylic acid product. The method is easy and convenient to operate, high in accuracy and precision and good in repeatability, and reliable technical support is provided for quality control and application and popularization of fatty alcohol-polyoxyethylene ether carboxylic acid products.

The present disclosure relates to the technical field of chloroacetic acid tail gas treatment, and one embodiment of the present disclosure provides a processing device for monochloroacetic acid synthesis tail gas, which comprises a first acetic acid absorption tower, a second acetic acid absorption tower, a third acetic acid absorption tower and a gas inlet pipeline, and further comprises heat preservation covers, sun protection covers, fixing mechanisms, heat preservation and sun protection mechanisms and connecting mechanisms, two heat preservation covers are movably sleeved on the first acetic acid absorption tower, the second acetic acid absorption tower and the third acetic acid absorption tower, and the sun protection covers are installed on the outer sides of the heat preservation covers. Through the above technical solution, the technical problem that the tail gas inlet pipeline and the acetic acid recovery tower in the processing device for monochloroacetic acid synthesis tail gas lack effective heat preservation and sun protection structures in the prior art, so that the temperature inside the tail gas inlet pipeline and the acetic acid recovery tower is affected by the outside world and rises, the tail gas is greatly lost when the air temperature is high, and the tail gas is easily greatly lost, thereby affecting the recovery efficiency of acetic acid is solved.

The invention provides a soluble cellulose-based alcohol disinfection wet tissue and a preparation method thereof.The preparation method comprises the steps that cellulose-based non-woven fabric is placed in a sealed container, and a first mixed solution composed of ethyl alcohol, water and sodium hydroxide is introduced into the sealed container; a second mixed solution composed of ethyl alcohol and monochloro fatty acid is introduced into the sealed container, then the temperature is raised and kept, the monochloro fatty acid is composed of monochloro acetic acid and other acids, the other acids are selected from at least one of monochloro propionic acid, monochloro butyric acid and monochloro valeric acid, and the mass ratio of monochloro acetic acid to other acids is (20-30): 1; cooling to below 30 DEG C, introducing a third mixed solution composed of ethanol and acetic acid into the sealed container, and keeping; emptying the solution in the sealed container, introducing a 75% ethanol aqueous solution, keeping, discharging the liquid, and then introducing a 75% ethanol aqueous solution for keeping. The method is efficient and convenient in production and low in energy consumption, and the prepared soluble disinfection wet tissue has excellent solubility and mechanical properties.

The invention provides a bio-based filtrate reducer as well as a preparation method and application thereof. The environment-friendly zwitterionic bio-based filtrate reducer is obtained by taking waste small dragon shrimp and crab shells as raw materials, treating the raw materials by adopting an acid-alkali method to obtain glycosaminoglycan, performing carboxylation modification on the glycosaminoglycan through monochloroacetic acid, and copolymerizing the glycosaminoglycan with a propenyl monomer, a quaternary ammonium salt monomer and 2-acrylamide-2-methylpropanesulfonic acid. The bio-toxicity EC50 value of the bio-based filtrate reducer provided by the invention is greater than 100000 mg / L, the biodegradability BOD / CODcr value is greater than 0.05, and the bio-based filtrate reducer belongs to a non-toxic and easily degradable level; the prepared filtrate reducer has good filtrate reduction property and temperature resistance at normal temperature and 100-200 DEG C, and still has excellent temperature resistance and salt resistance after being added into brine base slurry or saturated brine; the prepared filtrate reducer is wide in raw material source and low in price, can be applied to geological drilling operation to maintain the stability of a well wall, and provides guarantee for smooth proceeding of the geological drilling operation.