31 results about "Methyl lactate" patented technology

The invention relates to the technical field of water pollution control and treatment, in particular to a methyl lactate production wastewater treatment device, which comprises a wastewater component, a wastewater treatment component and a wastewater treatment component, the feeding assembly comprises a ratchet wheel disc rotationally arranged in the wastewater tank and a storage barrel arranged at the bottom of the ratchet wheel disc; the flocculation assembly comprises vibrating rods which are arranged outside the stirring shaft in a circular array manner; the transmission assembly comprises a pawl piece arranged on the outer wall of the stirring shaft, and the pawl piece is meshed with the ratchet wheel disc; wherein the pawl piece knocks the vibration rod when rotating along with the stirring shaft, and the pawl piece is disengaged from the ratchet disc when being in contact with the vibration rod; the feeding assembly realizes batch feeding of the flocculating agent, the concentration of the flocculating agent in the whole reaction process can be maintained in an optimal interval, the flocculation reaction rate is further accelerated through vibration of the flocculation assembly, and the settling performance is improved.

This invention discloses a green synthesis method for acid-base bifunctional molecular sieves and its application. The method constructs acid-base sites in a one-step synthesis, yielding a molecular sieve catalyst containing acid-base bifunctional sites. This molecular sieve exhibits high activity and stable performance, and can be used as a catalyst to catalyze the isomerization of glucose to fructose. It significantly improves conversion efficiency in reactions catalyzing the isomerization of high-concentration glucose to fructose or its conversion to methyl lactate. Furthermore, this synthesis method avoids the use of environmentally harmful fluorinated mineralizers and inorganic acids, solving the problems of complex, time-consuming, and environmentally unfriendly synthesis processes of existing acid-base bifunctional molecular sieves. It also addresses the issues of low reaction efficiency and low selectivity of existing catalysts in reactions catalyzing the conversion of high-concentration glucose.

The application discloses a method for recovering lactic acid methyl ester by catalytic depolymerization of polylactic acid in one pot. The method comprises the following steps: mixing polylactic acid, amine nitrogen ligand and methanol, dissolving by adding a solvent, and then adding a n-butyllithium solution to carry out a depolymerization reaction; and after the reaction is completed, the solvent is removed by vacuum distillation, and the crude product is dried in vacuum to obtain lactic acid methyl ester product. The application does not need to synthesize a complex organic metal catalyst, the depolymerization condition is mild, and the generation of by-products such as low-molecular-weight oligomers is effectively reduced. Therefore, the application has the advantages of simplifying the catalyst preparation process, improving the depolymerization efficiency, reducing the cost and the like, and is suitable for industrialized recovery and cyclic utilization of polylactic acid.

The application discloses a preparation method of an important intermediate of a pyrimidine-4(3H)-ketone heterocyclic compound shown in formula h, namely a preparation method of (3S,4S)-tert-butyl 4-((R)-1,1-dimethylethylsulfinamido)-3-methyl-2-oxa-8-azaspiro[4.5]decane-8-carboxylate, which is synthesized through a series of reactions such as substitution, reduction, nucleophilic addition, reduction and deprotection, ring closure, oxidation and reductive amination and the like by taking L-methyl lactate as a raw material. In the application, red aluminum is used to replace lithium borohydride and tetrabutylammonium fluoride in the prior art, so that the problems of the risk caused by the use of lithium borohydride and the difficulty in post-treatment caused by the use of tetrabutylammonium fluoride in the prior art are overcome, the reaction steps are shortened, and the post-treatment operation is simplified.

The application designs a method for preparing optically active methyl fluoropropionate by using diethylamine sulfur trifluoride, comprising the following steps: fluorination reaction: under the protection of nitrogen, methyl S-lactate is added to a dry reaction kettle as raw material, the kettle temperature is cooled to a first reaction temperature, diethylamine sulfur trifluoride is added dropwise into the reaction kettle, after dropping, the reaction kettle is heated to a second reaction temperature, after the reaction is completed, the reaction mixture is added dropwise into saturated sodium / potassium bicarbonate aqueous solution to obtain R-2-fluoropropionic acid methyl ester; the molar ratio of diethylamine sulfur trifluoride to methyl S-lactate is 1-1.5:1, the method is high in efficiency, low in three-waste amount, short in reaction path, suitable for industrial production, and has economic value.

The environmentally friendly spinning polymer solution for generating a nanofibrous structure in an electrostatic field includes a polymer, a solvent system, and possibly other additives to modify the conductivity of the solution. The polymer at a concentration of 10 to 20 wt% is at least one polymer from the group consisting of polylactic acid (PLA), polysulfone (PSU), polyurethane (PU), and cellulose acetate (CA). The solvent system is a green solvent system comprising at least two of the green solvents selected from the group consisting of cyclopentanone (CPO), ethyl lactate (EL), methyl lactate (ML), and acetone. The nanofibrous nonwoven fabric, which can be prepared by spinning the mentioned spinning polymer solution, contains nanofibers with an average diameter of 100 to 500 nm.

The invention relates to the technical field of industrial cleaning, and particularly discloses a low-toxicity degradable PCB (Printed Circuit Board) cleaning agent as well as a preparation method and application thereof. The low-toxicity degradable PCB cleaning agent is characterized by being prepared by mixing the following raw materials in percentage by weight: 50%-90% of D-methyl lactate, 10%-30% of isopropanol, 0-5% of glucoside and 0-5% of benzotriazole. The cleaning agent is reasonable in formula, all the components are synergistic, and the cleaning agent has the characteristics of being high in cleaning efficiency, mild to a base material and environmentally friendly, is free of residues after volatilization, is free of corrosion and damage to metal parts, is suitable for cleaning the surfaces of various materials such as electronic elements and metal workpieces, is especially suitable for precise cleaning of copper-containing metal parts, and has good application prospects. The application prospect is wide.

The invention discloses 2-amino-6-[(2-hydroxypropionyl) amino] hexanoic acid and a preparation method and application thereof, and belongs to the technical field of synthesis and utilization of small molecular compounds, methyl lactate and lysine are used as raw materials and react at the temperature of 15-35 DEG C, after the reaction is finished, a mixture is subjected to solid-liquid centrifugal separation, lower-layer solids are taken and washed with ethyl acetate, and the 2-amino-6-[(2-hydroxypropionyl) amino] hexanoic acid is obtained. And repeatedly centrifuging for three times, and drying at low temperature to obtain a milk white product 2-amino-6-[(2-hydroxy propionyl) amino] hexanoic acid. According to the 2-amino-6-[(2-hydroxy propionyl) amino] hexanoic acid as well as the preparation method and the application thereof, methyl lactate and lysine are subjected to direct acylation reaction at room temperature to synthesize the 2-amino-6-[(2-hydroxy propionyl) amino] hexanoic acid, and the obtained product simultaneously contains a methyl lactate structure and a lysine structure; the product is a key product of histone lysine milk acylation modification, and can be used for cardiovascular disease treatment and green chemical intermediates.

The invention provides a method for detecting methyl lactate in a sodium lactate solution, a gas chromatography is combined with a headspace sampling technology, and chromatographic conditions are as follows: a chromatographic column is a capillary column taking polyethylene glycol or a compound with similar polarity as a stationary liquid; a sample inlet is 180 DEG C, and headspace sample injection is performed; a flame ionization detector is adopted, and the temperature is 230 DEG C; the carrier gas is nitrogen, the flow velocity is 2.0 ml / min, and the split ratio is 10: 1; the column temperature program is as follows: 35 DEG C is maintained for 3 minutes, the temperature is raised to 90 DEG C at 5 DEG C / min and maintained for 3 minutes, and then the temperature is raised to 200 DEG C at 15 DEG C / min and maintained Headspace conditions are as follows: the balance temperature of a headspace bottle is 90 DEG C, and the time is 30 minutes; a quantitative loop is 100 DEG C; the temperature of the transmission line is 110 DEG C; the circulation time is 40 minutes. The method can accurately and quantitatively detect methyl lactate, is convenient to operate, and has great significance in improving the quality control level of the sodium lactate solution, guaranteeing the application safety of the sodium lactate solution in the fields of medicines and foods and perfecting a quality standard system.

According to the technical scheme, the method comprises the following steps that 1, activated carbon is added into water, heating and stirring are conducted, suction filtration is conducted after stirring is conducted, then solids are collected and dried, and activated AC is obtained; 2, adding all AC into the HNO3 aqueous solution, heating and stirring, and condensing and refluxing for 3-15 hours; after the reflux is finished, washing a product to be neutral, and drying overnight to obtain AC-H; 3, transferring AC-H into a NaOH aqueous solution, stirring at normal temperature, and then washing to be neutral to obtain AC-H-Na; 4, polylactic acid, AC-H-Na and absolute methanol are added into a reaction kettle, the temperature is increased to the specified temperature in the nitrogen environment for a reaction, and methyl lactate is obtained; the method adopts nitric acid and sodium hydroxide step-by-step modified activated carbon as a catalyst to catalyze degradation of polylactic acid, has high catalytic efficiency, and the catalyst is easy to recover, and reduces reaction energy consumption at the same time; belongs to the technical field of polymer degradation.

The invention relates to the technical field of high polymer materials, in particular to a one-step sequence-controlled hydroxy acid block copolyester preparation method, which comprises: carrying out amine catalysis on mandelic acid and bromoacetyl bromide in acetonitrile to form ester, cyclizing with sodium bicarbonate in N, N-dimethylformamide, and recrystallizing to obtain PDD; the preparation method comprises the following steps: carrying out Mannich reaction on 2, 4-di-tert-butylphenol to obtain a ligand H3L, complexing the ligand H3L with zirconium alkoxide, and carrying out methyl lactate treatment to obtain [ONOO]-Zr; pDD and epsilon-caprolactone are heated and polymerized in the presence of a [ONOO]-Zr catalyst, benzoic acid is terminated, and precipitation and purification are performed to obtain sequence-controlled block copolyester P (PDD-b-CL). Compared with other sequence-controlled block copolymer synthesis methods, the one-step sequence-controlled hydroxy acid block copolyester preparation method provided by the invention has the advantages of mild reaction conditions and simplicity and convenience in operation.

The application discloses a water-soluble morpholine lactic amide acrylate bio-based monomer and a polymer thereof, and belongs to the technical field of bio-based polymers.The application uses a lactic acid derived green solvent (methyl lactate, ethyl lactate, propyl lactate, butyl lactate and the like) and morpholine to synthesize morpholine lactic amide ester (MML) through amine ester exchange under solvent-free mild conditions, then synthesizes a polymerizable morpholine lactic amide acrylate monomer (MMLA) through acylation reaction and tests the performance through various means.The research finds that the water-soluble bio-based monomer (MMLA) of the morpholine lactic amide acrylate developed by the application has lower toxicity than traditional acrylate monomers and can be polymerized in a more environmentally friendly system, and the water-soluble polymer obtained after polymerization has high glass transition temperature and good thermal stability, and the water-soluble polymer with lower biological toxicity and good stability has application prospects in the development of biomedical fields.

The invention discloses a preparation method of tiopronin, and belongs to the technical field of organic synthesis. The process comprises the following three steps of: 1, carrying out amine ester exchange reaction on glycine tert-butyl ester and methyl lactate in an organic solvent under the action of alkali to generate 2-hydroxy propionyl glycine tert-butyl ester; 2, enabling 2-hydroxy propionyl glycine tert-butyl ester and thioacetic acid to generate an intermediate 2 under the action of dialkyl azo dicarboxylate and triaryl phosphine / trialkyl phosphine; and 3, hydrolyzing the intermediate 2 in an organic solvent under the action of acid and alkali in sequence, and carrying out deprotection to generate tiopronin. According to the technical scheme, operation is easy, convenient and stable, products in all steps are easy to separate, the yield is high, environment friendliness is achieved, and a new synthesis way is provided for the compound.

The invention relates to the technical field of waste polystyrene treatment, in particular to a biodegradable modified waste polystyrene film and a preparation method thereof. The problem existing in the prior art is that waste styrene is modified into a biodegradable polystyrene material through conventional chemical grafting, an initiator or a catalyst needs to be additionally added, and the recycling cost is high. In order to solve the problems, the invention provides the biodegradable modified waste polystyrene film, through ester exchange reaction of methyl lactate and a PS molecular chain under specific conditions, a lactate group is directly grafted to a PS main chain, and the problem of non-degradability of PS is solved from the chemical structure. The whole modification process is carried out under heating and sealing conditions, the transesterification reaction is driven by utilizing the properties of reactants, an initiator or a metal catalyst commonly used in traditional grafting modification is omitted, the post-treatment step is simplified, and the production cost is reduced.

Janus dry facial mask based on birch emulsion electrospinning and its preparation method belong to the field of beauty and skin care materials technology. This invention first utilizes green bio-based solvents ethyl lactate or methyl lactate to optimize the extraction of betulinol from birch bark using an ultrasound-assisted method. Then, employing emulsion electrospinning technology and a Janus bilayer structure design, an asymmetric bilayer dry facial mask is constructed: the hydrophobic layer is made of biodegradable polylactic acid electrospinned, acting as a water-locking barrier to delay moisture loss; the hydrophilic layer is made by uniformly dispersing birch bark ethyl lactate extract (oil phase) in a mixed aqueous solution of polyvinyl alcohol and chitosan through high-speed shear emulsification to form a stable O / W type emulsion, followed by electrospinning to create a nanofiber membrane encapsulating active ingredients. The Janus dry facial mask exhibits excellent moisturizing, antioxidant, and anti-inflammatory effects, and requires no preservatives for dry storage and transportation. The process is simple and suitable for industrial production.

The invention discloses biodegradable gel and a method for removing paint on the surfaces of stone cultural relics, and relates to the technical field of stone cultural relic protection. The biodegradable gel comprises the following components in percentage by weight: 30-60% of a bio-based main solvent, 10-30% of a bio-based cosolvent, 5-15% of biogel, 1-10% of a thickening stabilizer and the balance of water, the bio-based main solvent is one or more of methyl lactate, ethyl lactate, propyl lactate and butyl lactate, the bio-based cosolvent is one or more of limonene, terpinene, methyltetrahydrofuran and gamma-valerolactone, and the bio-gum is one or more of xanthan gum, guar gum, carrageenan, locust bean gum and sesbania gum. The thickening stabilizer is one or more of bentonite, kaolin, attapulgite and diatomite. The degradable gel has the advantages of favorable swelling property, biodegradability, no toxicity, safety to the environment and operators, no strong acid substance and capability of preventing the surface of the stone cultural relic from being crisp when in use.

The invention relates to the technical field of epsilon-CL-20 crystal material preparation, in particular to a spherical epsilon-CL-20 crystal preparation method and system.The method comprises the steps that CL-20 and methyl lactate are prepared into a saturated solution, circulating concentration is carried out in a crystallizer through a nanofiltration membrane assembly, and meanwhile through control over the transmembrane pressure and the outflow rate of penetrating fluid, the spherical epsilon-CL-20 crystal is obtained; the supersaturation degree of the solution is precisely regulated and controlled, and closed-loop circulation of the solvent is realized through real-time recovery and resaturation of penetrating fluid. The green solvent methyl lactate is adopted, the membrane crystallization technology is combined for operation at normal temperature, and the method has the advantages of low energy consumption, zero solvent emission, controllable crystal morphology, uniform particle size distribution and the like, and is suitable for industrial continuous production of high-purity spherical epsilon-CL-20 crystals.

The invention discloses a zeolite catalyst as well as a preparation method and application thereof, and belongs to the technical field of catalysts. The invention provides a preparation method of a zeolite catalyst. The preparation method comprises the following steps: carrying out heat treatment on aluminum-containing zeolite to remove a template agent in the aluminum-containing zeolite; the roasted zeolite is obtained. And carrying out acid treatment on the roasted zeolite to remove Al in the zeolite so as to obtain the dealuminated zeolite. The method comprises the following steps: by taking dealuminated zeolite as a silicon source and tetraethylammonium hydroxide as a template agent, adding a zinc source, and carrying out evaporation treatment to obtain a mixture; performing pre-crystallization treatment on the mixture, and adding a mineralizing agent to form gel; and carrying out crystallization treatment and roasting treatment on the gel to obtain the zeolite catalyst. When the prepared zeolite catalyst is used, thermodynamic limitation is broken through, high polylactic acid conversion rate and high methyl lactate yield are obtained at mild temperature and pressure, and the technical problems that a traditional polylactic acid methanol depolymerization catalyst is difficult to separate, poor in effect, complex to synthesize and toxic are solved.

The invention relates to the technical field of chemical synthesis, and discloses a preparation method of 2-[2-(tetrahydropyranyl) oxy] methyl propionate. The preparation method of the 2-[2-(tetrahydropyranyl) oxy] methyl propionate comprises the following steps: taking methyl lactate and 3, 4-dihydro-2H-pyran as reaction raw materials, reacting under the catalysis of an IL1 / MCM-41 catalyst and a solvent-free condition, and after the reaction is finished, separating the catalyst to obtain a finished product of the 2-[2-(tetrahydropyranyl) oxy] methyl propionate. The IL1 / MCM-41 catalyst is a heterogeneous catalyst formed by loading a disulfonic functionalized ionic liquid IL1 on an MCM-41 mesoporous molecular sieve. The preparation method disclosed by the invention is mild in reaction condition, simple and convenient to operate, high in conversion rate and selectivity, and capable of meeting green chemical requirements, and has a remarkable industrial application prospect, and the catalyst can be recycled through simple filtration and can be repeatedly used for multiple times.

The invention belongs to the field of chemical engineering and pesticides, and particularly relates to a preparation method of a fluonamate intermediate, 3, 5-dichloro-2, 6-difluoro-4-aminopyridine and (R)-methyl lactate are used as raw materials, and the fluonamate intermediate is generated through a nucleophilic substitution reaction. According to the present invention, with the easily available raw materials, the simple and easily-controlled process, the high yield and the high ee value can be obtained;

The invention relates to the field of adhesives, and discloses a polylactic acid tow adhesive for cigarettes as well as a preparation method and application of the polylactic acid tow adhesive. The polylactic acid tow adhesive for the cigarette comprises a solute and a filler, wherein the solute is one or more of extra white hydrogenated rosin, hydrogenated rosin, polyvinyl acetate, ethylene-vinyl acetate copolymer, cellulose acetate and nitrocellulose; the organic solvent is one or more of glycerol triacetate, L-methyl lactate, L-ethyl lactate, L-butyl lactate, propylene glycol diacetate and ethylene glycol diacetate. The polylactic acid tow adhesive for the cigarette is simple to prepare and good in bonding effect, can be cured at normal temperature to improve the hardness of a filter stick, and does not influence the smoking taste of the polylactic acid filter stick.

The application discloses a method for synthesizing methyl lactate by catalyzing selective oxidation esterification of 1,2-propanediol, which comprises the following steps: contacting oxygen, 1,2-propanediol and a catalyst in a reactor, and reacting to obtain methyl lactate; the catalyst is composed of a metal oxide carrier and gold elements loaded on the surface of the metal oxide carrier; in the catalyst, the mass of the gold elements is 0.1-2 wt% of the mass of the metal oxide carrier; and the metal oxide carrier is at least one selected from SiO2, ZnO, gamma-Al2O3, TiO2, CeO2, MgO and Sm2O3.

The invention discloses a method for catalyzing the degradation of polylactic acid by modified activated carbon. The technical scheme comprises the following steps: step 1: adding activated carbon to water, heating and stirring, filtering after stirring, collecting solids and drying to obtain activated activated carbon; step 2: adding all the activated carbon to an HNO3 aqueous solution, heating and stirring, and condensing and refluxing for 3-15 hours; after the reflux is completed, washing the product to neutrality, and drying overnight to obtain activated carbon; step 3: transferring activated carbon to a NaOH aqueous solution, stirring at room temperature, and then washing to neutrality to obtain activated carbon, thereby obtaining activated carbon; and step 4: adding polylactic acid, activated carbon, and anhydrous methanol to a reactor, heating to a specified temperature under a nitrogen environment for reaction, thereby obtaining methyl lactate. The method uses activated carbon modified with nitric acid and sodium hydroxide in steps as a catalyst to catalyze the degradation of polylactic acid, has high catalytic efficiency, is easy to recover the catalyst, and reduces reaction energy consumption. The method belongs to the technical field of polymer degradation.

The present invention discloses a method for preparing methyl lactate by catalytic conversion of biomass sugars with metal-loaded titanium silicate molecular sieve in near-critical methanol. The steps of the method are as follows: 1) Add biomass sugars and methanol into a high-temperature and high-pressure reactor, where the mass concentration of biomass sugars is 10-200 g / L, and then add a metal-loaded titanium silicate molecular sieve catalyst. The mass ratio of biomass sugars to the metal-loaded titanium silicate molecular sieve is 5:1 - 1:3; 2) Heat up to 140-220 °C and react for 0.5-36 h; 3) After the reaction is completed, cool to room temperature, filter, and the filtrate is rectified to obtain a methyl lactate product, and the methanol is recycled; the filter residue is the used metal-loaded titanium silicate molecular sieve, which is directly recycled after being washed with methanol and dried. The present invention uses a metal-loaded titanium silicate molecular sieve as a catalyst, which not only has a very high yield of methyl lactate, but also has high catalyst stability and good reusability, so it has a very broad industrial application prospect.

The invention discloses a method for removing hydrogen peroxide in a synthetic process of a pyruvic acid intermediate. The preparation method comprises the following steps: dispersing cucurbituril and persulfate in a hydrochloric acid solution under a protective atmosphere, adding a propenyl compound, and heating and stirring for reaction; and after the reaction is finished, sequentially filtering, washing and drying to obtain the cucurbituril bonded polymer. After the reaction for preparing the methyl pyruvate by oxidizing the methyl lactate is finished, adding the cucurbituril bonded polymer into a reaction system and stirring; after the peroxide is completely consumed, insoluble substances in a reaction system are filtered and separated, leaching and drying are carried out until the weight is constant, and the cucurbituril bonded polymer is regenerated and can be recycled. The cucurbituril bonded polymer can remove hydrogen peroxide in a reaction solution, and can be regenerated and recycled through simple treatment. Not only can hydrogen peroxide in a methyl pyruvate reaction system be effectively removed, but also the cost of synthesizing methyl pyruvate is reduced.

The invention belongs to the technical field of preparation of high-end high-purity wet electronic chemicals, and particularly relates to a preparation method and system of electronic-grade ethyl lactate. According to the method, food-grade ethyl lactate is taken as a raw material, ethyl pyruvate which is difficult to separate is reduced into ethyl lactate through reduction reaction, ethyl lactate homologues (methyl lactate, propyl lactate and butyl lactate) and light and heavy component impurities in the ethyl lactate are removed through vacuum distillation, and finally anions and cations in the ethyl lactate are removed through resin adsorption, so that the ethyl lactate is obtained. The content of the obtained ethyl lactate is higher than 99.99%, the anion content is smaller than or equal to 10 ppb, the metal ion content is smaller than or equal to 1 ppb, the acidity is smaller than or equal to 80 ppm, the moisture content is smaller than or equal to 100 ppm, and the requirements of electronic-grade ethyl lactate are met. The method can effectively remove ethyl pyruvate and ethyl lactate homologues which are difficult to remove in ethyl lactate, and has the advantages of low cost, low energy consumption, high production efficiency, environmental protection and the like.

The invention belongs to the field of chemical engineering and pesticides, and particularly relates to a preparation method of (S)-2-methyl chloropropionate, which is characterized in that (R)-methyl lactate serving as a raw material and thionyl chloride are subjected to chlorination in the presence of a catalyst to generate the (S)-2-methyl chloropropionate. (S)-2-methyl chloropropionate is obtained with high yield and high ee value, and industrial popularization and application are facilitated.

The invention discloses a preparation method of a key intermediate of a macrocyclic auxin-releasing peptide receptor modulator, which comprises the following steps: by taking 3-(2-methoxyphenyl) propionic acid as a raw material, preparing 3-(2-methoxyphenyl) propionamide through substitution reaction, reducing the 3-(2-methoxyphenyl) propionamide into 3-(2-methoxyphenyl) propylamine, removing methoxy to prepare 2-(3-aminopropyl) phenol, and preparing the key intermediate of the macrocyclic auxin-releasing peptide receptor modulator. The preparation method comprises the following steps: preparing N-[3-(2-phenolic phenyl) propyl] phenylmethyl carbamate through a substitution reaction, carrying out a substitution reaction on the N-[3-(2-phenolic phenyl) propyl] phenylmethyl carbamate and methyl lactate, and finally reducing to generate N-[3-[2-[(1R)-2-hydroxy-1-methyl ethyoxyl] phenyl] propyl] phenylmethyl carbamate; the method has the advantages of mild reaction, high yield, high purity, environmental protection, safety and reliability, and can provide a macrocyclic auxin-releasing peptide receptor modulator key intermediate with abundant sources and low cost for preparation of related products in the field of biological medicine.

The application discloses a kind of heterogeneous catalyst Au / Sn-Beta and its application in glycerol oxidation preparation methyl lactate, belong to catalytic synthesis technical field, Au site in the heterogeneous catalyst is oxidation active center, Sn site of Sn-Beta molecular sieve is Lewis acid center, using organic template agent guiding strategy, gold species is precisely anchored in Sn-Beta molecular sieve carrier, catalyst activation can be completed in low-temperature air atmosphere.Rely on the prepared Au / Sn-Beta catalyst, it can efficiently catalyze glycerol oxidation preparation methyl lactate;The catalyst preparation process of the application is simple, and the operating condition is safe and easy to control, and the reproducibility is good, with innovation and good application prospect.

The application discloses a butter dirt on-line cleaning agent and a preparation method and application thereof. The butter dirt on-line cleaning agent comprises the following components in mass percentage: alkyl polyglycoside 8-20 wt%, fatty alcohol polyoxyethylene ether compound 8-25 wt%, composite chelating agent 10-15 wt%, methyl lactate 10-20 wt%, and the rest is deionized water; wherein the composite chelating agent is a mixture of sodium gluconate and glutamic acid. The butter dirt on-line cleaning agent is uniform and stable, can quickly remove butter dirt in an alkali washing tower of an ethylene production device, and is extremely convenient to operate when used, without stopping and opening the tank for cleaning, only needing to be added into the alkali washing tower with alkali liquor. Meanwhile, raw materials of the butter dirt on-line cleaning agent are non-toxic and non-polluting, the preparation method is simple, and the butter dirt on-line cleaning agent is suitable for large-scale production and application in industry.