- Tin-catalyzed conversion of trioses to alkyl lactates in alcohol solution
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Tin chlorides, SnCl2 and SnCl4·5H2O are excellent catalysts for the reactions of trioses, dihydroxyacetone and glyceraldehyde with alcohols (MeOH, EtOH and nBuOH) to give alkyl lactates, whose reaction mechanism involves the intermediary formation of pyruvic aldehyde followed by its esterification, which is distinctively promoted by tin halides. The Royal Society of Chemistry 2005.
- Hayashi, Yukiko,Sasaki, Yoshiyuki
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- Hydroxyapatite supported lewis acid catalysts for the transformation of trioses in alcohols
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We prepared hydroxyapatite-supported tin(II) chloride and tin(IV) chloride Lewis acid catalysts. These catalysts showed catalytic activity for the transformation of trioses in alcohols to yield alkyl lactates. Under optimal conditions, n-butyl lactate was obtained in 73.5 yield when dihydroxyacetone and n-butanol were treated with hydroxyapatite-supported tin(II) chloride.
- Zhang, Zehui,Zhao, Zongbao
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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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- Zeolite-catalysed conversion of C3 sugars to alkyl lactates
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The direct conversion of C3 sugars (or trioses) to alkyl lactates was achieved using zeolite catalysts. This reaction represents a key step towards the efficient conversion of bio-glycerol or formaldehyde to added-value chemicals such as lactate derivatives. The highest yields and selectivities towards the desired lactate product were obtained with Ultrastable zeolite Y materials having a low Si/Al ratio and a high content of extra-framework aluminium. Correlating the types and amounts of acid sites present in the different zeolites reveals that two acid functions are required to achieve excellent catalysis. Bronsted acid sites catalyse the conversion of trioses to the reaction intermediate pyruvic aldehyde, while Lewis acid sites further assist in the intramolecular rearrangement of the aldehyde into the desired lactate ester product. The presence of strong zeolitic Bronsted acid sites should be avoided as much as possible, since they convert the intermediate pyruvic aldehyde into alkyl acetals instead of lactate esters. A tentative mechanism for the acid catalysis is proposed based on reference reactions and isotopically labelled experiments. Reusability of the USY catalyst is demonstrated for the title reaction.
- Pescarmona, Paolo P.,Janssen, Kris P. F.,Delaet, Chloe,Stroobants, Christophe,Houthoofd, Kristof,Philippaerts, An,De Jonghe, Chantal,Paul, Johan S.,Jacobs, Pierre A.,Sels, Bert F.
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- Development of lactic ester as bifunctional additive of methanol-gasoline
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In this paper, lactic esters were synthesized and used as phase stabilizer and saturation vapor pressure depressor of methanol-gasoline. The results show that the stabilities of the methanol-gasoline depend on the length of the lactic esters' alkoxy group. Several lactic esters were found to be effective in various gasoline-methanol blends, and the lactic esters display high capacity to depress the saturation vapor pressure of methanol-gasoline. According to the results, it can be concluded that the lactic esters have the great potential to be bifunctional gasoline-methanol additives.
- Zhang, Jie,Yang, Changchun,Tang, Ying,Xu, Lianghong,Wang, Xiaoting
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- Adsorption and Reactive Desorption on Metal–Organic Frameworks: A Direct Strategy for Lactic Acid Recovery
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Biomass-derived lactic acid (LA) is an important platform chemical towards the sustainable production of numerous materials. However, the fermentation process currently in use is limited by the difficult recovery of the LA product from the fermentation broth and results in the generation of stoichiometric amounts of gypsum waste. Herein, we show that metal–organic frameworks (MOFs) of the UiO-66(Zr) type are effective adsorbents for the separation of LA from aqueous (buffer) solutions. These frameworks based on zirconium clusters and terephthalic acid derivatives display a tremendous uptake (up to 42 wt %) and a high affinity for LA. The latter can further be tuned by changing the hydrogen-bonding properties of the functional groups present on the organic ligand. A Rietveld refinement disclosed the specific interaction of LA with the clusters of UiO-66(Zr) and a preferential adsorption on open zirconium sites. Taking advantage of the catalytic activity of UiO-66(Zr), desorption of LA was performed in alcohols to recover up to 73 % as ester. Applied to the recovery of LA, adsorption and reactive desorption offer a direct and gypsum-free strategy as an alternative for the current multi-step process.
- Stassin, Timothée,Reinsch, Helge,Van de Voorde, Ben,Wuttke, Stefan,Medina, Dana D.,Stock, Norbert,Bein, Thomas,Ameloot, Rob,De Vos, Dirk
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- The Role of Surface Termination in Halide Perovskites for Efficient Photocatalytic Synthesis
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Halide perovskites have received attention in the field of photocatalysis owing to their excellent optoelectronic properties. However, the semiconductor properties of halide perovskite surfaces and the influence on photocatalytic performance have not been systematically clarified. Now, the conversion of triose (such as 1,3-dihydroxyacetone (DHA)) is employed as a model reaction to explore the surface termination of MAPbI3. By rational design of the surface termination for MAPbI3, the production rate of butyl lactate is substantially improved to 7719 μg g?1 cat. h?1 under visible-light illumination. The MAI-terminated MAPbI3 surface governs the photocatalytic performance. Specially, MAI-terminated surface is susceptible to iodide oxidation, which thus promotes the exposure of PbII as active sites for this photocatalysis process. Moreover, MAI-termination induces a p-doping effect near the surface for MAPbI3, which facilitates carrier transport and thus photosynthesis.
- Bai, Yang,Chen, Qi,Deng, Kailin,Dong, Yuanyuan,Guan, Haoliang,Li, Kailin,Li, Yujing,Luo, Wenjia,Wang, Hao,Wang, Lanning,Xie, Haipeng,Zhou, Huanping,Zhu, Cheng
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- HETEROGENEOUS CATALYST COMPLEX FOR CARBON DIOXIDE CONVERSION
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Proposed is a catalyst complex having high activity for carbon dioxide conversion reaction that converts carbon dioxide to useful compounds through reaction of carbon dioxide and hydrocarbon containing at least one hydroxyl group, and a carbon dioxide conversion process using the same, wherein the catalyst complex includes, as an active metal in the catalyst complex, at least one of noble metals and at least one of transition metals other than noble metals, thereby having high activity for the carbon dioxide conversion reaction.
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Paragraph 0158-0162
(2021/05/21)
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- Method for preparing lactate
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The invention relates to a method for preparing lactate. The method comprises the following steps: contacting pyruvic aldehyde and alcohol with a catalyst in a reactor, and reacting to obtain a lactate-containing product, wherein the molar ratio of the pyruvic aldehyde to the alcohol is 1:(20-225), the reaction temperature is 30-180 DEG C, the reaction time is 1-10 hours, the catalyst contains a mixture of a titanium-silicon molecular sieve and a tin-silicon molecular sieve, and the weight ratio of the pyruvic aldehyde to the mixture of the titanium-silicon molecular sieve and the tin-siliconmolecular sieve based on dry basis weight is 1:(0.1-6). The method provided by the invention has high pyruvic aldehyde conversion rate and high lactate yield.
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Paragraph 0086-0087
(2020/06/30)
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- Method for preparing lactate
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The invention relates to a method for preparing lactate. The method comprises the following steps of: contacting sugar and alcohol with a catalyst in a reactor, and reacting to obtain a lactate-containing product, wherein the molar ratio of the sugar to the alcohol is 1:(50-900), the reaction temperature is 150-250 DEG C, the reaction time is 10-50 hours, the catalyst contains a mixture of a titanium-silicon molecular sieve and a tin-silicon molecular sieve, and the weight ratio of the sugar to the mixture of the titanium-silicon molecular sieve and the tin-silicon molecular sieve based on drybasis weight is 1:(0.1-6). The method provided by the invention has high sugar conversion rate and high lactate yield.
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Paragraph 0086-0087
(2020/06/30)
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- Robust acidic pseudo-ionic liquid catalyst with self-separation ability for esterification and acetalization
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The novel acidic pseudo-ionic liquid catalyst with self-separation ability has been synthesized through the quaternization of triphenylphosphine and the acidification with silicotungstic acid. The pseudo-IL showed high activities for the esterification with average conversions over 90%. The pseudo-IL showed even higher activities for acetalization than traditional sulfuric acid. The homogeneous catalytic process benefited the mass transfer efficiency. The pseudo-IL separated from the reaction mixture automatically after reactions, which was superior to other IL catalysts. The high catalytic activities, easy reusability and high stability were the key properties of the novel catalyst, which hold great potential for green chemical processes.
- Shi, Yingxia,Liang, Xuezheng
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p. 1413 - 1421
(2019/05/04)
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- Method for directly preparing lactate from 1,2-propanediol and short-chain alkyl alcohols
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The invention belongs to the technical field of organic matter synthesis, and particularly relates to a method for directly preparing lactate from 1,2-propanediol and short-chain alkyl alcohols, and the method comprises the following steps: using a sodium stannate loaded rare noble metal as a catalyst, adding C1-C4 alkyl alcohols and the 1,2-propanediol into a high-pressure reaction kettle, usingnitrogen for purging air in the kettle, heating and stirring while the temperature is maintained to promote esterification of the 1,2-propanediol with the C1-C4 alkyl alcohols after oxidation of the 1,2-propanediol to produce the lactate. The method has mild reaction conditions and simple reaction steps, the 1,2-propanediol is completely converted, and the highest selectivity of the lactate can reach 78%. Meanwhile, the synthesized sodium stannate loaded rare noble metal has high catalytic activity and reusability.
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Paragraph 0054; 0057-0058; 0060-0061; 0063
(2019/10/15)
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- Production of lactic acid derivatives from sugars over post-synthesized Sn-Beta zeolite promoted by WO3
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Various metal oxides were used as co-catalysts to improve the production of alkyl lactate over Sn-Beta-P. WO3 exhibited the best promotion effect. The yield of MLA increased from 25% (6.5 g L?1) over Sn-Beta-P (0.2 g) to 52% (13.4 g L?1) over WO3 (0.1 g) and Sn-Beta-P (0.1 g) at 160 °C for 5 h and 3.1 wt% of glucose concentration. MLA yield of 38% was attained even at glucose concentration of 10 wt% and the space-time yield reached 7.1 g L?1 h?1. The action mechanism of WO3 was investigated. Fine WO3 particles adsorbed on surface of Sn-Beta-P in reaction media and decreased the silanol defects of Sn-Beta-P. This promotes retro-aldol of fructose, the rate-determining step of whole reaction, thus facilitated the formation of MLA. Kinetic studies indicate that the presence of WO3 decreased the activation energy of the retro-aldol of fructose. The binary solid WO3 and Sn-Beta-P is recyclable.
- Yang, Xiaomei,Zhang, Yali,Zhou, Lipeng,Gao, Beibei,Lu, Tianliang,Su, Yunlai,Xu, Jie
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p. 285 - 291
(2019/03/21)
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- Method for synthesizing high-purity butyl lactate
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Provided is a method for synthesizing high-purity butyl lactate, and relates to the technical field of organic chemical synthesis. The method comprises the steps of: adopting lactic acid as a raw material, performing a reaction between the lactic acid and alkaline inorganic matter at a ratio in water to obtain lactate, performing distillation to remove water, performing a reaction between the lactate and n-butyl halide, and performing washing and rectification to obtain the high-purity butyl lactate, wherein the molar ratio of the lactic acid, alkaline inorganic matter and n-butyl halide is (1:0.5:1)-(1:1.1:1.5), the alkaline inorganic matter which is used for preparing the lactate includes one or a combination of more selected from sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, sodium hydroxide and potassium hydroxide, and the n-butyl halide is one or a combination of more selected from n-butyl chloride and n-butyl bromide. The method has the advantages of low-cost raw materials, less equipment investment, mild reaction conditions and simple operation, and since water is adopted as a reaction solvent, the method is environmentally friendly and has low cost; the product can be purified easily, the purity can reach 99% or above, the yield can reach 95% or above, and therefore the method has a high economic value.
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Paragraph 0014; 0015; 0016; 0017;
(2018/05/16)
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- SEPARATION OF ORGANIC ACIDS FROM MIXTURES CONTAINING AMMONIUM SALTS OF ORGANIC ACIDS
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The invention relates to a process for separation of organic acids from mixture of ammonium salts of one or more organic acids and other compounds via an integrated process. The process involves suspending mixture of ammonium salts of one or more organic acids and other compounds in dry hydrocarbon solvent/s or mixtures thereof; wherein the selected hydrocarbon solvent/s or mixtures thereof have boiling point more than 100° C. and forms an azeotrope with water. The reaction mixture thus obtained is dehydrated azeotropically followed by esterification of basic salt of the organic acids by addition of alcohol in presence of metal or metal salt; thereafter the individual esters formed are separated by distillation and hydrolysed to obtain corresponding organic acids having more than 98% purity.
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Paragraph 0065; 0066; 0072
(2018/06/30)
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- Preparation method of carbon-silicon solid acid catalyst and application in extraction of organic acid in fermentation broth
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The invention discloses a preparation method of a carbon-silicon solid acid catalyst and application in extraction of organic acid in fermentation broth. The method comprises the following steps: swelling: heating and co-hydrolyzing soluble starch with high content of straight chain molecules and silicate ester for 2 h, aging at room temperature for 1-2 days, exchanging moisture in the system with an organic solvent with lower surface tension than water, and drying; carbonization activation: carrying out one-step carbonization activation by using soluble inorganic salt or strong base under nitrogen protection; and sulfonation: carrying out sulfonation on a carbon-silicon composite material by the use of concentrated sulfuric acid, so as to obtain the carbon-silicon solid acid catalyst. The catalyst is used for extraction of low-concentration organic acid in various fermentation broths. The invention has the following advantages: the synthetic method is green, raw materials are easily available, and discharge of spend liquor and exhaust gas is less; dispersity in an aqueous solution is high; hydrophilicity is strong, and acid value is high; the synthesized material has large specific surface area; synthesis cost is low; catalytic effect is good; and the catalyst can be repeatedly used for many times.
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Paragraph 0086
(2017/06/06)
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- PROCESS FOR SYNTHESIZING LACTIC ESTERS
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A method for synthesizing lactic ester is disclosed. Lactic ester can be effectively produced from lactic acid and a alcohol in the presence of mixed catalysts containing titanium and aluminum. Under identical reaction conditions, the mixed catalysts exhibits higher lactic ester yield than the single titanium catalyst and the single aluminum catalyst.
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Page/Page column 8; 9; 10
(2018/04/17)
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- Esterification technique of butyl lactate
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The invention relates to an esterification technique of butyl lactate. The technique comprises the following steps: by using lactic acid and butanol in a mass ratio of 1:1 as raw materials and dichromic acid as a catalyst (the mass ratio of the catalyst to the lactic acid is 1:200), proportioning, adding a novel catalyst, and carrying out esterification with stirring and water diversion while strictly controlling the esterification reaction temperature and esterification reaction time, thereby obtaining butyl lactate; and carrying out distillation and refinement. The technique has the characteristics of lower requirements for facility tool sets, simple preparation method, flexible reaction time and high product yield, does not need to add alkalis for neutralization since the catalyst has weak acidity, solves the problem of facility corrosion, and is safe and environment-friendly. The technique has the advantages of environment friendliness, high economy and high efficiency.
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Paragraph 0013-
(2017/09/08)
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- Lactate Production Process
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A process for producing alkyl R-lactate from an initial compound comprising substructure (I) is provided. The process involves producing an intermediate comprising R,R- and S,S-lactide from the initial compound, wherein the initial compound is subjected to stereoisomerisation conditions; and reacting at least a portion of the intermediate with an alkyl alcohol to produce a product comprising alkyl R-lactate, wherein alkyl R-lactate is produced in the presence of an enzyme. Also provided are processes for the production of R-lactic acid, oligomeric R-lactic acid, R,R-lactide, poly-R-lactic acid and stereocomplex lactic acid.
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(2015/06/10)
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- Highly effective continuous-flow monolithic silica microreactors for acid catalyzed processes
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This work reports the performance of a new monolithic silica microreactor, activated with sulphonic acid groups in the continuous-flow synthesis of n-butyl acetate and n-butyl lactate. A reactive core of the reactor was made of a single silica rod with bi-continuous structure, containing flow-through pores with diameter in the range of 20-50 μm and mesopores of ca. 20 nm localized in silica struts. This structure resulted in low pressure drop, even at flow rates large enough to eliminate external mass transfer effect on the reaction kinetics. The microreactor functionalized with 0.65mmol/g of-SO3H groups showed high activity and productivity in both esterification reactions carried out in temperatures up to 140 °C. Structural and catalytic stability of the microreactor was confirmed to demonstrate its process viability.
- Koreniuk,Maresz,Odrozek,Jarz?bski,Mrowiec-Bia?oń
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p. 203 - 208
(2015/05/05)
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- PROCESS FOR PRODUCING A LACTIC ACID-AMINE COMPLEX
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A process for the production of a complex of lactic acid and either ammonia or an amine, comprising: a) reacting a stream rich in saccharide with sodium hydroxide to produce a reaction mixture comprising sodium lactate; b) contacting at least a portion of the reaction mixture with ammonia or an amine and with carbon dioxide, or with the carbonate and/or bicarbonate salt of ammonia or an amine, to produce sodium carbonate and/or bicarbonate and a stream rich in said complex; c) reacting at least a portion of the sodium carbonate and/or bicarbonate with an alkaline earth metal hydroxide to produce sodium hydroxide and alkaline earth metal carbonate, wherein the alkaline earth metal is selected from the group consisting of calcium and magnesium; and d) recycling at least a portion of the sodium hydroxide produced in step c) to step a).
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Page/Page column 13
(2015/11/03)
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- LACTATE PRODUCTION PROCESS
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A process for producing lactic acid is provided. The process comprises (a) reacting a stream rich in saccharide with sodium hydroxide in the presence of water to produce a reaction mixture comprising sodium lactate; (b) reacting at least a portion of the sodium lactate with HCl to produce lactic acid and sodium chloride; (c) converting at least a portion of the sodium chloride to chlorine and sodium hydroxide; and (d) recycling at least a portion of the sodium hydroxide produced in step (c) to step (a). Also provided are processes for the production of alkyl lactate, oligomeric lactic acid, lactide, alkyl lactyllactate, poly-lactic acid, propylene glycol and acrylic acid.
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Page/Page column 22; 23
(2015/03/28)
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- MONOMER, POLYMER, RESIST COMPOSITION, AND PATTERNING PROCESS
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A polymer comprising recurring units derived from a (meth)acrylate monomer of tertiary ester type having branched alkyl on alicycle is used to form a resist composition. When subjected to exposure, PEB and organic solvent development, the resist composition is improved in dissolution contrast.
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- PROCESS FOR PRODUCING A LACTIC ESTER FROM A FERMENTATION LIQUOR CONTAINING AMMONIUM LACTATE
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The present invention relates to an industrial process for producing a lactic ester containing in total at least seven carbon atoms, from a fermentation liquor containing ammonium lactate in order to avoid the inherent production of gypsum, with a high yield and according to which the loss of lactic ester in the form of lactamide is limited as much as possible.
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Paragraph 0039; 0040; 0041; 0042
(2013/10/22)
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- One step catalytic conversion of cellulose to sustainable chemicals utilizing cooperative ionic liquid pairs
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A 100% conversion of cellulose to industrially useful chemicals is, for the first time, achieved in a single pot reaction by the use of cooperative ionic liquid pairs for combined dissolution and catalytic degradation of cellulose, which overcomes the long intrinsic phase problem in the conversion of biomass to chemicals.
- Long, Jinxing,Guo, Bin,Li, Xuehui,Jiang, Yanbin,Wang, Furong,Tsang, Shik Chi,Wang, Lefu,Yu, Kai Man K.
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supporting information; experimental part
p. 2334 - 2338
(2011/10/12)
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- Continuous Process for Obtaining a Lactic Ester
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Continuous method for obtaining a lactic ester, characterised in that it comprises the following steps: a) esterification reaction of a composition comprising an alcohol in the presence of a composition comprising lactic acid in excess,b) extraction of a vapour phase from this reaction medium, containing lactic ester, alcohol, water and traces of lactic acid;c) distillation of the vapour phase obtained at step b) in order to recover the lactic ester, alcohol and water at the top;d) distillation of the fraction obtained at step c) in order to recover the purified lactic ester at the bottom.
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Page/Page column 4
(2011/07/08)
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- Ultrasound-assisted solvent-free synthesis of lactic acid esters in novel SO3H-functionalized Br?nsted acidic ionic liquids
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Mild and efficient Fischer esterification reactions of lactic acid with a variety of straight chain aliphatic alcohols, cyclohexanol and benzyl alcohol were successfully performed using two novel Br?nsted acidic ionic liquids that bear an aromatic sulfonic acid group on the imidazolium or pyridinium cation under ultrasound irradiation. These reactions carried out smoothly with good to excellent conversion rate (78-96%) and satisfactory yields (73-92%) in shorter reaction time (4-6 h) at room temperature when the amount of ionic liquids was 20 mol%. These ionic liquids could be recovered readily and recycled five times without any significant loss in their catalytic activity.
- Li, Xinzhong,Lin, Qi,Ma, Liang
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experimental part
p. 752 - 755
(2011/10/08)
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- ZEOLITE-CATALYZED PREPARATION OF ALPHA-HYDROXY CARBOXYLIC ACIDS AND ESTERS THEREOF
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A process for the production of lactic acid and 2-hydroxy-3-butenoic acid or esters thereof by conversion of glucose, fructose, sucrose, xylose and glycolaldehyde dissolved in a solvent in presence of a solid Lewis acidic catalyst.
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Page/Page column 3
(2010/06/11)
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- Zeolite-catalyzed preparation of alpha-hydroxy carboxylic acid compounds and esters thereof
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A process for the production of lactic acid and 2-hydroxy-3-butenoic acid or esters thereof by conversion of glucose, fructose, sucrose, xylose and glycolaldehyde dissolved in a solvent in presence of a solid Lewis acidic catalyst.
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Page/Page column 6
(2010/06/11)
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- Heteropolyanion-based ionic liquids: Reaction-induced self-separation catalysts for esterification
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(Figure Presented) It comes out in the wash: In the esterification of citric acid with n-butanol, heteropolyanion-based ionic liquid (IL) catalysts show high catalytic activity, self-separation, and easy reuse. The good solubility in reactants, nonmiscibility with ester product, and high melting point of the IL catalysts enable the reaction-induced switching from homogeneous (b in the picture) to heterogeneous (c) with subsequent precipitation of the catalyst (d).
- Leng, Yan,Wang, Jun,Zhu, Dunru,Ren, Xiaoqian,Ge, Hanqing,Shen, Lei
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experimental part
p. 168 - 171
(2009/04/18)
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- A CONTINUOUS PROCESS FOR THE PREPARATION OF ALKYL ESTERS OF LACTIC ACID AND ALIPHATIC ALCOHOLS
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The present invention relates to a continuous processes for producing of alkyl esters of lactic acid by reaction of lactic acid, oligomers or/and polymers and its alkyl esters with alcohol. The present method is characterized by that process is carried out in a solution of a target product at mole ratio alcohol/lactic acid, oligomers or/and polymers and its alkyl esters at an initial mix less 1.
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Page/Page column 5
(2008/12/08)
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- Stereoselective reduction of carbonyl compounds with actinomycete: Purification and characterization of three α-keto ester reductases from Streptomyces avermitilis
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We achieved the purification of three α-keto ester reductases (Streptomyces avermitilis keto ester reductase, SAKERs-I, -II, and -III) from Streptomyces avermitilis NBRC14893 whole cells. The molecular masses of the native SAKERs-I, -II, and -III were estimated to be 72, 38, and 36 kDa, respectively, by gel filtration chromatography. The subunit molecular masses of SAKERs-I, -II, and -III were also estimated to be 32, 32, and 34 kDa, respectively, by SDS-polyacrylamide gel electrophoresis. The purified SAKERs-II and -III showed a reducing activity for α-keto esters (in particular, for ethyl pyruvate). SAKER-I showed a high reducing activity not only toward the α- and β-keto esters, but also toward α-keto acid. The N-terminal region amino acid sequences of SAKERs-I, -II, and -III were identical to that of a putative oxidoreductase, SAV2750, a putative oxidoreductase, SAV1849, and a putative oxidoreductase, SAV4117, respectively, hypothetical proteins coded on the S. avermitilis genome.
- Ishihara, Kohji,Kato, Chiaki,Yamaguchi, Hitomi,Iwai, Rieko,Yoshida, Momoko,Ikeda, Natsumi,Hamada, Hiroki,Masuoka, Noriyoshi,Nakajima, Nobuyoshi
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body text
p. 3249 - 3257
(2009/04/10)
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- METHOD FOR PRODUCING LACTIC ACID ESTER
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This invention provides a method for producing a lactic acid ester that can minimize input energy at the time of production, that can reduce chemical costs, and that can minimize equipment costs. This method comprises steps of: performing an esterification reaction in a reaction solution containing ammonium lactate obtained via fermentation and alcohol with an ammonia concentration of 1.0% by weight or lower; and recovering the lactic acid ester synthesized in the above step.
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Page/Page column 9-10
(2008/06/13)
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- A facile, catalytic and environmentally benign method for esterification of carboxylic acids and transesterification of carboxylic esters with nearly equimolar amounts of alcohols
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A practical and green chemical process for the esterification of carboxylic acids with alcohols and transesterification of carboxylic esters in good to excellent yields by using K5CoW12O14· 3H2O (0.1 mol%) as catalyst is reported. The catalyst exhibited remarkable reusable activity. Georg Thieme Verlag Stuttgart.
- Bose, D. Subhas,Satyender, Apuri,Das, A. P. Rudra,Mereyala, Hari Babu
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p. 2392 - 2396
(2008/02/08)
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- PROCESS FOR THE PRODUCTION OF METAL SALTS OF TRIFLUOROMETHANE SULPHONIC ACID AND THEIR USE AS ESTERIFICATION CATALYSTS
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The subject matter of the invention is a process for the production of metal salts of trifluoromethane sulphonic acid by reacting trifluoromethane sulphonic acid with a metal alcoholate and the use thereof as esterification catalyst and/or transesterification catalyst for the production of hydroxycarboxylic acid esters.
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Page/Page column 12; 14
(2008/06/13)
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- A mild and efficient method for esterification and transesterification catalyzed by iodine
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Iodine, was found to be a practical and useful Lewis acid catalyst for the esterification of carboxylic acids with alcohols. The high catalytic activity of iodine can be used for the transesterification of esters by different alcohols including tertiary alcohols and sterically hindered primary and secondary alcohols. The method presented is especially effective for simultaneous esterification and transesterification reactions.
- Ramalinga,Vijayalakshmi,Kaimal
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p. 879 - 882
(2007/10/03)
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- Process for the preparation of alkyl esters from commercial lactic acid
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The present invention relates to a catalyst-free process for the conversion of commercial lactic acid to alkyl ester of carbon C1to C8which comprises simultaneous hydrolysis of dimers or highpolymers of lactic acid present in commercial lactic acid to free lactic acid and esterification of free lactic acid with an alcohol in the presence of water at a temperature in the range of 130-250° C. for 4-11 hrs at a pressure of 5-25 kg/cm2, to obtain desired esters.
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- Separation of methylene chloride from tetrahydrofuran by extractive distillation
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Methylene chloride is difficult to separate from tetrahydrofuran by conventional distillation or rectification because of the proximity of their vapor pressures. Methylene chloride can be readily separated from tetrahydrofuran by extractive distillation. Effective agents are 1-pentanol, 1,2-butanediol and 3-nitrotoluene.
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- Recovery of hydroxy acids from trash
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This invention is a method for recovering hydroxy acid values from a poly(hydroxy acid) containing source, said method comprising, in order: (a) contacting the source with a solubilizing fluid in an amount of at least 1 mole of solubilizing fluid per mole of hydroxy acid equivalent present in the source, said solubilizing fluid selected from the group consisting of (1) water, (2) alcohols containing 1 to 6 carbon atoms, (3) mixtures of water and said alcohols, (4) amines of the formula HNR1R2, wherein R1 and R2 are independently selected from the group consisting of hydrogen and alkyl groups of 1-4 carbon atoms; (5) liquid media containing diamines of the formula H(R3)NR5N(R4)H, wherein R3 and R4 are independently selected from the group consisting of hydrogen and alkyl groups of 1-4 carbon atoms or are joined to form a heterocyclic ring, and R5 is alkylene of 2-12 carbon atoms or phenylene; and (6) mixtures of said amines and/or diamines with water and/or alcohols containing 1 to 6 carbon atoms.
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- Propulsion process for lightweight miniature toy boats
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The invention is a propulsion process for lightweight miniature toy boats which comprises the interaction of certain organic compounds containing certain chemical radicals with water in such manner as to temporarily increase the surface tension of water in the vicinity of application to said boats resulting in a propulsion force to propel said boats with sufficient speed and sustained activity as to constitute a novel and interesting toy for young children.
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- Preparation of alkyl esters by depolymerization
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Depolymerizing polyhydroxy acid by heating with the alcohol of 1-6 carbon atoms in the presence of an acid catalyst to produce an alkyl ester.
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- Production of hydroxy carboxylic compounds
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This invention relates to a process for the production of alpha-hydroxy carboxylic compounds such as lactic acid or its ester by reacting a carbonyl compound having at least one hydroxyl group alpha to the carbonyl function with a hydroxy compound of the formula R3OH at elevated temperature in the presence of a transition metal compound as catalyst. Lactic acid and lactates produced by this process are items of commerce and are useful as solvents and chemical intermediates.
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- Triphenylphosphine Dibromide: Effective and Selective Reagent for the Cleavage of Acetals
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Triphenylphosphine dibromide (PPh3Br2) is a mild and highly effective reagent for hydrolysis of various acetals in dichloromethane at low temperature.
- Wagner, Alain,Heitz, Marie-Paule,Mioskowski, Charles
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p. 1619 - 1620
(2007/10/02)
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