Dimethyl Glutarate Research Articles

Vapor-liquid equilibrium phase behavior of binary systems of carbon dioxide with dimethyl succinate or dimethyl glutarate

BackgroundTo develop process for separating dimethyl succinate (DMS) and dimethyl glutarate (DMG) with the aid of supercritical carbon dioxide, the vapor-liquid equilibrium (VLE) data of the related mixtures are fundamentally important. The VLE data were determined experimentally and correlated with various thermodynamic models in this study. MethodsThe isothermal VLE data were measured for carbon dioxide + DMS and carbon dioxide + DMG by using a semi-flow and a static types of apparatuses at temperatures from 313.15 K to 413.15 K and pressures up to 20 MPa. These VLE data were correlated with the Krichevsky-Ilinskaya (KI) equation, the Soave-Redlich-Kwong (SRK), the Peng-Robinson (PR) and the Patel-Teja (PT) equations of state incorporating with two-parameter one-fluid van der Waals mixing rules (vdW-2). Significant findingsThe results of this study provide the VLE data of carbon dioxide + DMS and + DMG and reveal the VLE phase transition behavior, especially crossing near critical region. The Henry's constant and critical loci were also estimated. The Peng-Robinson equation of state with the vdW-2 mixing rule yielded the best data correlation results. The optimal values of the binary interaction parameters were also obtained, which can be used in the separation process simulation and design.

Non-targeted analysis of unknown volatile chemicals in medical masks.

This paper reports the non-targeted analysis of unknown volatile chemicals in medical masks through headspace gas chromatography-Orbitrap high-resolution mass spectrometry. In view of the difficulties that may be encountered in the qualitative analysis of unknown substances, several typical cases and the corresponding reliable solutions are given from the perspective of comprehensive score and retention index, chemical ionization identification molecular formula, fragment ion detail comparison for distinguishing isomers, and identification of alkanes. With this method, 69 volatile substances were identified in 60 masks. The identified substances were divided into nine categories. Alkanes, esters, benzenes, and alcohols were the top four groups of substances identified in masks and accounted for 34.8%, 15.9%, 10.1%, and 7.2% of the total substances, respectively. In addition, ketones, ethers, phenolics, amides, and other substances were identified. Ethanol, 1,4-dichlorobenzene, toluene, m-xylene, dimethyl glutarate, and N,N-dimethylacetamide had high detection rates. The identified substances were further filtered and screened according to their detection rate, toxicity, and response intensity. Finally, 12 high-risk volatile chemicals in medical masks were listed. This study could serve as a reference for identifying unknown substances and a guide for monitoring volatile chemicals in masks and promoting chemical safety improvements in products.

Effect of Coriander Plants on Human Emotions, Brain Electrophysiology, and Salivary Secretion.

Simple SummaryThis research aims to investigate the effects of coriander plants on human emotions and physiological activities. The results showed coriander plants could significantly reduce the angry sub-scores, alpha amylase and amino acids (arginine, proline, histidine, and taurine) concentrations in saliva. Theta (4–8 Hz) band activity of the cerebral cortex was significantly enhanced. Moreover, taurine significantly positively correlated with anger and negatively correlated with vigor. All the results signified that coriander plant could influence the activity of brain electrophysiological and salivary secretion through its VOCs to improve people’s negative emotions. This study will provide a theoretical basis for the living coriander plants have some therapeutic effect on the human psychological state.Coriander is a popular herb with versatile applications. However, the current research about coriander medicinal values have been mainly focusing on its extracts while lacking in the relationship between living coriander plants and emotion. Therefore, this study aims to investigate the effects of coriander plants on human emotions and physiological activities. The results showed that the main Volatile organic compounds (VOCs) of coriander plants were 2-ethyl-1-hexanol, d-limonene, eucalyptol, benzyl alcohol, Isophorone, dimethyl glutarate, α-terpineol, styrene, methyl methacrylate, α-pinene. Coriander plants could significantly reduce the angry sub-scores, alpha amylase and amino acids (arginine, proline, histidine, and taurine) concentrations in saliva. Theta (4–8 Hz) band activity of the cerebral cortex was significantly enhanced. Moreover, taurine significantly positively correlated with anger and negatively correlated with vigor. All the results signified that coriander plant could influence the activity of brain electrophysiological and salivary secretion through its VOCs to improve people’s negative emotions.

Reactive extraction of cis,cis-muconic acid from aqueous solution using phosphorus-bonded extractants, tri-n-octylphosphineoxide and tri-n-butyl phosphate: Equilibrium and thermodynamic study

• The muconic acid extraction by TOPO and TBP have been done firstly in the literature. • Different solvents used to solve TOPO and TBP. • Kinetic studies of the extraction mucconic acid was studied firstly in the literature. cis,cis- Muconic acid falls under the category of carboxylic acids and finds application mostly in biodegradable polymers, agrochemicals, and the food industry. Owing to the high thermal reactivity based upon the two-terminal carboxylic groups present in their structure, the chemical industry has widely used carboxylic acids. The major obstacle encountered during the production of carboxylic acids is their recovery from aqueous solutions and fermentation media. Therefore, the recovery of HccMA by reactive extraction as a particular product capture method, using tri- n -octylphosphine oxide (TOPO) and tri- n -butyl phosphate (TBP) in organic diluents such as 1-butanol, isoamyl alcohol, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), diisobutyl ketone, isobutanol, n -hexane, dimethyl glutarate, ethyl propionate, and diethyl carbonate (DEC) was executed in this study. This method was experimentally conducted to explore the most proper extractant and diluent combination. Extraction experiments were also conducted with pure diluents alone to examine the extractant effect on the extraction system. The important extraction parameters like distribution coefficient ( K D ), extraction efficiency ( E %), loading ratio ( Z ), dimerization constant ( D ), partition coefficient ( P ), and complexation constant ( K E 11 ) were determined. Mass action law model interpreted the obtained results. For HccMA/TOPO extraction system, the maximum extraction efficiency was found 93.19% in the presence of n -hexane as a diluent. For HccMA/TBP extraction system, the maximum extraction efficiency was found 90.37% in the presence of ethyl propionate as a diluent. Thermodynamic studies at variable temperatures were also carried out to estimate ΔH, ΔS, and ΔG of the process. To investigate the feasibility of designing a counter-current liquid–liquid extraction column, the number of theoretical stages (NTS) were assessed by theodified Kremser equation and found between 3 and 5 to et the desired extraction efficiency.

Liquid–Liquid Equilibrium Measurement and Correlation for the Ternary Systems (Dimethyl Succinate + 1,4-Butanediol)/(Dimethyl Glutarate + 1,5-Pentanediol)/(Dimethyl Adipate + 1,6-Hexanediol) + Water at Different Temperatures

Liquid–liquid equilibria (LLE) data for esters + diols + water ternary systems were measured at 101.3 kPa at four different temperatures, namely, 293.15, 303.15, 313.15, and 323.15 K. The Othmer–To...

Determination and correlation of ternary isobaric vapour-liquid equilibrium data of (dimethyl succinate + dimethyl glutarate + dimethyl adipate) at 2, 5 and 8 kPa

Isobaric vapour-liquid equilibrium data of {dimethyl succinate (DMS) + dimethyl glutarate (DMG) + dimethyl adipate (DMA)} ternary system was measured at 2 kPa, 5 kPa and 8 kPa with a dynamic recirculating apparatus and the temperature ranged from 364.46 to 403.55 K. The experimental data was correlated with NRTL, Wilson and Uniquac models. The results showed that the maximum value of the root mean square deviation of the vapour phase mole fraction of the ternary system correlated by the three models is 0.0083, 0.0076 and 0.0084, respectively. The vapour-liquid equilibrium data of the ternary system was predicted by the interaction parameters of NRTL, Wilson and the Uniquac models in the literature. The results showed that the maximum value of the root mean square deviation of the vapour phase mole fraction of the ternary system predicted by the three models is 0.0547, 0.0471, and 0.0498, respectively. The deviation between the experimental value and the regression value or the predicted value was small, and both met the needs of design calculation of the engineering separation. The results obtained from the regression of experimental values are significantly better.

Solubilities of Adipic Acid, Glutaric Acid, and Succinic Acid in Dimethyl Glutarate + Methanol Mixtures: Experimental Measurement and Thermodynamic Modeling

In this work, the solubilities of adipic acid, glutaric acid, and succinic acid in methanol + dimethyl glutarate mixtures were measured by using the laser dynamic method under 101.3 kPa at T = 287....

Isobaric vapor–liquid equilibrium of three binary systems containing dimethyl succinate, dimethyl glutarate and dimethyl adipate at 2, 5.2 and 8.3 kPa

The isobaric vapor–liquid equilibrium (VLE) data for three binary systems of dimethyl succinate (DMS) + dimethyl glutarate (DMG), dimethyl succinate + dimethyl adipate (DMA) and dimethyl glutarate + dimethyl adipate were determined at 2, 5.2 and 8.3 kPa with a dynamic recirculating apparatus and the temperature ranged from 363.39 to 422.4 K. All the experimental data were verified to be thermodynamically consistent according to the Herington method and point to point method of Van Ness test. Afterwards, the VLE data were correlated with Nonrandom two-liquid (NRTL), Wilson and UNIQUAC activity coefficient models, and the interaction parameters of thermodynamic models of these three binary systems were obtained. The results indicated that the calculated values of these three models agreed well with the experimental data, while the NRTL model and UNIQUAC model provided a slightly better result than Wilson model. The calculated root mean square deviations of NRTL model for the temperature and vapor-phase mole fraction were less than 0.13 K, and 0.0023, respectively.

Quantitative Analysis of Glutaric Acid, mono-Methyl Glutarate and Dimethyl Glutarate by High Performance Liquid Chromatography

A large amount of binary acid mixture by-product is generated during the production process of adipic acid, in which the content of glutaric acid is the highest. Esterification-separation-hydrolysis method is one of the commonly used purification technological methods for glutaric acid in binary acid mixture. In addition to the main product glutaric acid, mono-methyl glutarate and dimethyl glutarate are the two important impurities in the hydrolysis reaction system. In this paper, a convenient, accurate quantitative analysis method is established using a HPLC with a SunFire C18 column (5 μm, 4.6 mm×150 mm) and CH3CN/H2O/CF3COOH (60:40:1, V/V/V) as the mobile phase. Glutaric acid, mono-methyl glutarate and dimethyl glutarate were baseline separated under a flow rate of 0.5 mL/min and a column temperature of 40 ℃. Under the optimal conditions, linear correlations were obtained in the mass concentration range of 6~3 000 mg/L (r=0.998 0) for glutaric acid, 3~1 500 mg/L (r=0.999 1) for mono-methyl glutarate, and 3~1 500 mg/L (r=0.999 4) for dimethyl glutarate. The recoveries (n=5) of glutaric acid, mono-methyl glutarate and dimethyl glutarate were 105.79% (RSD=1.63%), 96.21% (RSD=7.28%) and 93.10% (RSD=11.22%), respectively. Using this method the simultaneously determination of the contents of glutaric acid, mono-methyl glutarate and dimethyl glutarate, respectively can be carried out. Which can provide accurate and reliable data for the esterification-separation-hydrolysis process.

Metal-catalyzed reductive deamination of glutamic acid to bio-based dimethyl glutarate and methylamines

Glutamic acid was successfully converted into dimethyl glutarate and trimethylamine by a Pt based reductive deamination at 225 °C in methanol.

Determination in the air of workplace dimethyl succinate and dimethyl glutarate and dimethyl adipate by gas chromatography

目的：建立工作场所空气中混合二元酸二甲酯的溶剂解吸气相色谱测定方法。 方法：采用活性炭管采集，1%二甲基甲酰胺-二硫化碳溶液解吸，DB-624毛细管柱对样品进行分离，氢火焰离子化检测器测定，以保留时间定性，峰面积定量。 结果：该方法检测丁二酸二甲酯在5.62~280.00 mg/L、戊二酸二甲酯在4.25~271.00 mg/L、己二酸二甲酯在4.14~265.00 mg/L浓度有良好的线性关系，相关系数均≥0.999 9，检出限分别为0.19、0.16、0.18 mg/L，最低检出浓度分别为0.07、0.05、0.06 mg/m(3)，批内精密度分别为3.20%~4.54%、1.34%~3.93%、1.69%~2.73%，批间精密度分别为2.28%~3.59%、1.98%~3.22%、1.84%~3.05%，回收率分别为99.4%~100.1%、99.4%~99.9%、97.7%~100.1%，解吸效率分别为95.8%、95.2%、92.1%。 结论：该方法具有分离效果好、灵敏度高的优点，适用于工作场所空气中丁二酸二甲酯、戊二酸二甲酯及己二酸二甲酯的准确定性和定量检测。.

Lipases: An overview of its current challenges and prospectives in the revolution of biocatalysis

Abstract Over the past few years most of the biochemical industries are in a rapid stage of development. The major root cause responsible for this current state of excitement is a new technology-driven biocatalysis that pulled markets in to the new areas. The development of technology from scientific breakthroughs to the industrial applications is rapidly increasing all over the world. The substantial growth and increased emphasis on the development of biocatalysts is an huge achievement both for chemical and biotechnology related industries. In this present world ‘chemical biotechnology’ is rapidly growing hand-in-hand with maximum utilization of renewable feed stocks and made a big impact in the industrial revolution. The present review mainly summarizes a complete overview of lipases and its biocatalytic applications in pharmaceutical industries especially in the synthesis of (-)-Peroxetine hydrochloride, diltiazem hydrochloride, chiral β-azidoalcohols, primary amines and amides, vitamin D3 derivatives. The catalytic role of lipases in the epoxidation of unsaturated carboxylic acids, in the kinetic resolution of azirinol, aminolysis of dimethyl 3-substituted glutarates in addition to these lipase assisted synthesis of dihydropyrano [2,3-c] pyrazoles and 4-methoxy cinnamoyl glycerol was elaborated.

Male Pheromones Influence the Mating Behavior of Echinothrips americanus.

Two dibasic esters, the dimethyl ester of hexanedioic acid (dimethyl adipate, DBE-6) and the dimethyl ester of pentanedioic acid (dimethyl glutarate, DBE-5) were found in head-thorax extracts of male Echinothrips americanus. DBE-5 induced abdomen wagging and raising in males and females, which is typically exhibited when encountering a male. DBE-6 was avoided by males and was detected on mated, but not on virgin, females. Both substances applied to virgin females lead to females being ignored by males. The role of both substances is discussed with regard to the male mating system.

Monomethyl β-Methylglutarate of New Synthetic Methods

Malonate ethyl ester of butene in the presence of sodium hydroxide was synthesized by addition reaction of 2-methyl propane-1,1,3 tricarboxylic acid ester, by hydrolysis decarboxylation heatingβ-methyl glutaric acid. First with excess of methanol into methyl metaplasiaβ-methyl dimethyl glutarate, and then itsβ-methyl glutaric acid methylation, get high yield of monomethyl β-methylglutarate.

(Liquid + liquid) equilibria of the (water + carboxylic acid + dibasic esters mixture (DBE-2)) ternary systems

(Liquid+liquid) equilibrium (LLE) data for the {water+carboxylic acid+dibasic esters mixture (dimethyl adipate+dimethyl glutarate)} system were determined experimentally at T=298.2K for each acid. In this work, we studied formic acid, acetic acid and propionic acid. All the phase diagrams were obtained by determining solubility curve and tie-line data. The reliability of the experimental tie-line data was confirmed by using the Othmer–Tobias correlation. The UNIFAC and modified UNIFAC models were used to predict the phase equilibrium in the system determined from experimental data using the interaction parameters between CH2, CH3, HCOOH, COOH, CH3COO, and H2O functional groups. Distribution coefficients and separation factors were evaluated for the immiscibility region.

Effect of Pressure-Induced Changes in the Ionization Equilibria of Buffers on Inactivation of Escherichia coli and Staphylococcus aureus by High Hydrostatic Pressure

Survival rates of Escherichia coli and Staphylococcus aureus after high-pressure treatment in buffers that had large or small reaction volumes (ΔV°), and which therefore underwent large or small changes in pH under pressure, were compared. At a low buffer concentration of 0.005 M, survival was, as expected, better in MOPS (morpholinepropanesulfonic acid), HEPES, and Tris, whose ΔV° values are approximately 5.0 to 7.0 cm(3) mol(-1), than in phosphate or dimethyl glutarate (DMG), whose ΔV° values are about -25 cm(3) mol(-1). However, at a concentration of 0.1 M, survival was unexpectedly better in phosphate and DMG than in MOPS, HEPES, or Tris. This was because the baroprotective effect of phosphate and DMG increased much more rapidly with increasing concentration than it did with MOPS, HEPES, or Tris. Further comparisons of survival in solutions of salts expected to cause large electrostriction effects (Na2SO4 and CaCl2) and those causing lower electrostriction (NaCl and KCl) were made. The salts with divalent ions were protective at much lower concentrations than salts with monovalent ions. Buffers and salts both protected against transient membrane disruption in E. coli, but the molar concentrations necessary for membrane protection were much lower for phosphate and Na2SO4 than for HEPES and NaCl. Possible protective mechanisms discussed include effects of electrolytes on water compressibility and kosmotropic and specific ion effects. The results of this systematic study will be of considerable practical significance in studies of pressure inactivation of microbes under defined conditions but also raise important fundamental questions regarding the mechanisms of baroprotection by ionic solutes.

Synthesis of Dimethyl Glutarate from Cyclobutanone and Dimethyl Carbonate over Solid Base Catalysts

A facile route for the synthesis of dimethyl glutarate (DMG) from cyclobutanone and dimethyl carbonate (DMC) in the presence of solid base catalysts has been developed. It was found that the intermediate carbomethoxycyclobutanone (CMCB) was produced from cyclobutanone with DMC in the first step, and then CMCB was further converted to DMG by reacting with a methoxide group. The role of the basic catalysts can be mainly ascribed to the activation of cyclobutanone the abstraction of a proton in the -position by base sites, and solid bases with moderate strength, such as MgO, favor the formation of DMG.

Feasibility analysis, synthesis, and design of reactive distillation processes: A focus on double‐feed processes

AbstractA new approach for the feasibility analysis of reactive distillation processes based on the reactive extractive curve maps (rExCM) concept is introduced. A method dedicated to reactive distillation feasibility analysis, and design has been developed in our team since 1999. From minimal information concerning the physicochemical properties of the system, three steps lead to the design of the unit and the specification of its operating conditions. Currently, the procedure permits the conceptual design of hybrid reactive column configuration with one or two feed plates, for any number of equilibrium reactions (provided that the degree of freedom of the system is equal to 2) occurring in liquid or vapor phase. This contribution focuses on the most recent developments: the generalization of the feasibility analysis step to double‐feed processes thanks to the introduction of the rExCM concept. This methodology is illustrated through two examples: the emblematic methyl acetate example and the production of dimethyl methyl glutarate. © 2011 American Institute of Chemical Engineers AIChE J, 58: 2346–2356, 2012

Purification of l-Malic Acid from Aqueous Solution by a Method of Reactive Extraction

Malic acid is a C4-dicarboxylic acid and an intermediate of the tricarboxylic acid cycle. It has been widely used in the polymer, food, and pharmaceutical industries. Malic acid is produced by a fermentation process with a lot of bacteria in about between (8 and 10) % by weight aqueous solution. In this study, malic acid has been extracted from aqueous solution by reactive batch extraction in solvents with and without trioctyl methyl ammonium chloride (TOMAC or Aliquat 336). Five different constant concentrations of TOMAC have been prepared using five different esters (dimethyl phthalate, dimethyl adipate, dimethyl succinate, dimethyl glutarate, diethyl carbonate), five different alcohols (isoamyl alcohol, hexan-1-ol, octan-1-ol, nonan-1-ol, decan-1-ol), and two different ketones (diisobutyl ketone (DIBK), methylisobutyl ketone (MIBK)). The results have been reported as distribution coefficients (KD), loading factors (TT), stoichiometric loading factors (TS), separation factors (Sf), and extraction effici...

Solvent effects on the extraction of malic acid from aqueous solution by secondary amine extractant

Reactive extraction of malic acid was studied at 298 K. Experimental data on extraction of malic acid by Amberlite LA-2 dissolved in five different esters (dimethyl phthalate, dimethyl adipate, dimethyl succinate, dimethyl glutarate, diethyl carbonate), five different alcohols (isoamyl alcohol, hexan-1-ol, octan-1-ol, nonan-1-ol, decan-1-ol) and two different ketones (diisobutyl ketone (DIBK), methyl isobutyl ketone (MIBK)) were reported as distribution coefficients ( K D ), loading factors ( T T ), stoichiometric loading factors ( T S ), separation factors ( S f ) and extraction efficiencies ( E). Isoamyl alcohol was found to be the most effective diluent with a maximum distribution value ( K D ) of 83.807. The LSER model was found to correlate the experimental data satisfactorily.