- Preparation method of glycolic acid or glycolate
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The invention discloses a preparation method of glycolic acid or glycolate. The method comprises the following steps of: formaldehyde and carbon monoxide are introduced into a reactor containing a reaction solution to carry out polymerization reaction, wherein the reaction solution contains an acid catalyst; after the relative molecular mass of a polymer generated by the polymerization reaction reaches 2,000 and above, the polymerization reaction system is cooled to crystallize and precipitate the generated polymer; solid-liquid separation is carried out on the material in the reactor; and excessive water or alcohol is added into the obtained solid phase to carry out a depolymerization reaction to obtain glycolic acid or glycolate. Compared with the prior art, the method disclosed by the invention is good in process stability, low in energy consumption, good in economic practicability and high in product yield, and has a very good application prospect.
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Paragraph 0148-0150
(2020/09/20)
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- Retention Characteristics and Sorption Enthalpies of Esters of Natural Hydroxycarboxylic Acids on DB-1 Stationary Phase
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Abstract: Sorption characteristics and retention of esters of glycolic, lactic, malic, and tartaric acids with C1?C8 alcohols of linear structure are studied by gas-liquid chromatography in the temperature range of 90?260°C on DB-1 nonpolar phase. The values of the retention indices of the compounds studied are obtained. On the basis of experimentally determined retention times, the thermodynamic characteristics of sorption under the conditions of limiting dilution are estimated. The dependences of the change in sorption enthalpies on the length of the linear alkyl substituent and on the value of the logarithmic retention index are found. The possibility of estimating the energy of intermolecular interactions of lactic acid esters in the liquid phase is shown on the basis of the obtained values of sorption enthalpies and vaporization enthalpies.
- Portnova,Yamshchikova, Yu. F.,Krasnykh
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p. 577 - 583
(2019/06/03)
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- Preparation method of chlorophenoxyacetic ester
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The invention provides a preparation method of chlorophenoxyacetic ester, wherein the preparation method comprises the following steps: A) carrying out reaction of glycolic acid and alcohol in tolueneto obtain glycolic ester; B) carrying out reaction of glycolic ester and metal alkoxide to obtain a metal salt of glycolic ester; and C) carrying out reaction of the metal salt of glycolic ester andchlorobenzene to obtain the chlorophenoxyacetic ester. The chlorophenoxyacetic ester is synthesized by condensation of chlorobenzene with the metal salt of glycolic ester, the use of chlorophenol withunpleasant odor is effectively avoided, the production of highly toxic dioxins is eliminated, and the product quality and the operating environment of the production site are greatly improved. Motherliquor containing effective ingredients cannot be produced, so the loss of effective ingredients is effectively avoided and the yield of the product is improved.
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Paragraph 0046; 0047
(2019/01/08)
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- Hydroxy acetic acid n-butyl catalytic synthesis method
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The invention belongs to the technical field of chemical synthesis, and concretely relates to a catalytic synthesis method of n-butyl hydroxyacetate. The method comprises the following steps: carrying out a refluxing dehydrating esterification reaction on glycolic acid and an excess amount of n-butanol under the catalysis of acidic ion exchange resin, filtering, and distilling to synthesize n-butyl hydroxyacetate, wherein the acidic ion exchange resin is preprocessed by a buffer solution. Processing of the acidic ion exchange resin by the buffer solution with a certain pH value greatly improves the synthesis yield and selectivity of n-butyl hydroxyacetate. The method has the advantages of low device requirements, no corrosion and few three wastes, and is especially suitable for amplified production.
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Paragraph 0031; 0032; 0033; 0034; 0035; 0036; 0037-0049
(2017/09/23)
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- Natural preservatives
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In the present invention, provided is a compound, which has good antibacterial effects and is denoted by general formula (I), or a pharmaceutical acceptable salt thereof where R1 is saturated or unsaturated straight chains or branch chains of an alkyl group in general formula (I); R2 is hydrogen, methyl or is selected from a general formula (2); and R3 is hydrogen, saturated or unsaturated straight chains or branch chains of an alkyl group, and X is hydrogen or is selected from a hydroxyl group in general formula (2).COPYRIGHT KIPO 2015
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Paragraph 0055; 0056
(2016/12/26)
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- A continuous process for glyoxal valorisation using tailored Lewis-acid zeolite catalysts
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The aqueous-phase heterogeneously catalysed isomerisation of bio-oil derived glyoxal is herein introduced as a novel route for the sustainable production of glycolic acid. While commercial ultra-stable Y zeolites displayed only moderate performance, their evaluation enabled us to highlight the crucial role of Lewis acidity in the reaction. Gallium incorporation into these zeolites boosted the glycolic acid yield, although the best catalytic results were obtained over tin-containing MFI-type zeolites, reaching 91% yield of the desired product at full conversion. These materials comprised hydrothermally-synthesised Sn-MFI as well as a novel catalyst obtained by the introduction of tin into silicalite-1 by means of a simpler and more scalable method, i.e. alkaline-assisted metallation. In-depth spectroscopic characterisation of these systems uncovered a substantial similarity of the tin centres obtained by the top-down and bottom-up synthetic approaches. NMR spectroscopic studies gave evidence that the reaction follows a 1,2-hydride shift mechanism solely catalysed by Lewis-acid sites. The Sn-MFI analogue could be reused in 5 cycles without the need for intermediate calcination, did not evidence any tin leaching, and demonstrated suitability for utilisation under continuous-flow operation. The tin-based zeolites exhibited remarkable performance also in alcoholic solvents, leading to the one-pot production of relevant alkyl glycolates.
- Dapsens, Pierre Y.,Mondelli, Cecilia,Kusema, Bright T.,Verel, Rene,Perez-Ramirez, Javier
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p. 1176 - 1186
(2014/03/21)
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- Synthesis and application of glycolic esters in methanol-gasoline as bifunctional additives
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Summary : To explore new and multifunctional additives for methanol-gasoline, glycolic esters were synthesized and screened as phase stabilizer and saturation vapor pressure depressor. The effect of the esters' structure on the efficiency was discussed. It was found that the stability of the blends depend on the length of the glycolic esters' alkoxy group, and hexyl glycolic and octyl glycolic were found to be the most effective in various gasoline-methanol blends. Additionally, the glycolic esters can depress the saturation vapor pressure of methanol-gasoline effectively as well, and decyl glycolic is the most effective one. With these data, it can be concluded that the glycolic esters have the great potential to be used as bifunctional gasoline-methanol additives.
- Tang, Ying,Cheng, Qitong,Zhang, Jie,Yang, Changchun,Wang, Shanshan,Wang, Xiaoli,Zhao, Zhen
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p. 1109 - 1113
(2015/01/30)
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- Preparation and application of Hydroxyacetic Acid Esters as Methanol-Gasoline additives
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In this paper, hydroxyacetic acid esters (glycolic esters) were synthesized and used as phase stabilizer and saturation vapour pressure depressor of methanol-gasoline. The results show that the stabilities of the blends depend on the length of the glycoli
- Jiang, Xiaoyan,Tang, Ying
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p. 8447 - 8450
(2013/11/06)
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- MAKEUP COMPOSITION
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Composition for making up keratin fibres, such as eyelashes or eyebrows, having improved makeup-removing properties, containing in a continuous aqueous phase: an aqueous dispersion of a particular polyurethane present in an amount of solids greater than or equal to 5% by weight relative to the total weight of said composition, andsaid composition comprising an emulsifying system comprising less than 2% by weight of triethanolamine.
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- Ionic liquids as solvent for efficient esterification of carboxylic acids with alkyl halides
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The selective esterification of carboxylic acid derivatives with a variety of alkyl halides was carried out using ionic liquid as solvent in the presence of triethylamine. The reaction was found to proceed under relatively mild conditions with excellent conversions (up to 99%) and selectivities. The ionic liquid was recycled and reused. TUeBITAK.
- Goek, Yetkin,Alici, Buelent,Cetinkaya, Enginc,OeZdemir, Ismail,Oezeroglu, Ozlem
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experimental part
p. 187 - 191
(2010/09/11)
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- BIORESPONSIVE POLYMER SYSTEM FOR DELIVERY OF MICROBICIDES
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The polymer systems of the present invention degrade in the presence of an ejaculate. They may further provide degradable sequences that degrade upon contact with an ejaculate and/or microbicides. The polymer systems of the present invention are of use in the oral, rectal or vaginal cavities of an individual for such purposes as the treatment or prevention of sexually transmitted disease, the prevention or promotion of fertility or for hormone replacement therapy.
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Page/Page column 27
(2010/02/14)
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