Esters-buliding-blocks

Chen, Yao published the artcileMicrowave-assisted hydrodistillation extraction based on microwave-assisted preparation of deep eutectic solvents coupled with GC-MS for analysis of essential oils from clove buds, Application In Synthesis of 140-11-4, the main research area is microwave hydrodistillation gas chromatog mass spectrometry oil clove bud.

In recent years, deep eutectic solvents (DESs) as green and sustainable solvents have been widely used in the effective extraction of natural products. Usually, DESs are synthesized by heating and stirring method which takes a long time and energy. In this case, a microwave assisted preparation technique was used to form DESs for saving time and energy. And the DESs as pretreatment solvents were combined with microwave-assisted hydrodistillation (MAHD) for the extraction of essential oils (EOs) from the clove buds in this work. The maximum essential oils yield of 4.60% was obtained with the microwave power of 600 W, the pretreatment time of 5 min and the hydrodistillation time of 40 min using a deep eutectic solvent composed of choline chloride and lactic acid (molar ratio with 1:2). In addition, the essential oil was analyzed by gas chromatog.-mass spectrometry (GC-MS), a total of 40 compounds were identified. Compared with MAHD, water-based MAHD and traditional hydrodistillation (HD), the content and composition of essential oil extracted by DES-based MAHD were higher. Thus, the combination of deep eutectic solvents with a microwave-assisted technique in this study provided an eco-friendly way of extracting essential oils.

Sustainable Chemistry and Pharmacy published new progress about Cell wall. 140-11-4 belongs to class esters-buliding-blocks, name is Benzyl acetate, and the molecular formula is C9H10O2, Application In Synthesis of 140-11-4.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

He, Yunfei published the artcileSulfated complex metal oxides solid acids with dual Bronsted-Lewis acidic property for production of 5-ethoxymethylfurfural from biomass-derived carbohydrates, Computed Properties of 539-88-8, the main research area is sulfated metal oxide production ethoxymethylfurfural biomass derived carbohydrate.

The transformation of aldose-based carbohydrates into 5-ethoxymethylfurfural (EMF) is very challenging as compared to ketose-based carbohydrates, but the formers are more abundant and cheaper. Here, a series of sulfated complex metal oxides was synthesized for the conversion of aldose-based mono-, di-, and poly-saccharides, as well as starchy food waste into EMF. The catalysts were carefully characterized and the results showed that the type and strength of the acid sites were more important than their concentration It was also shown that the efficiency of these catalysts was significantly affected by the metal species in the catalyst composition and followed the order tetra- > tri- > bi- > mono-component metal oxides based catalyst. Among the prepared catalysts, Zr-Sn-Fe-Al-O-S exhibited superior catalytic activity, with an EMF yield of 33.1% from glucose, and yields ranging from 4.1-26.3% for di-, poly-saccharides and starchy food waste in ethanol/dimethyl sulfoxide solvent system under glucose/catalyst mass ratio of 4. The role of co-solvent in the reaction pathway was also studied. It was found that the predominant reaction pathway for EMF production was closely related to the co-solvent amount A kinetic model of glucose conversion to EMF was developed and the thermodn. anal. was performed, the main features of the exptl. observations can be described by the model. Zr-Sn-Fe-Al-O-S was reused for four runs without intermediate regeneration steps, showing a slight decay in activity. After reactivation by calcination before the fifth cycle, the catalyst recovered its activity, indicating good reusability and thermal stability.

Chemical Engineering Journal (Amsterdam, Netherlands) published new progress about Catalysts. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Computed Properties of 539-88-8.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Liu, Zhong-Qiu published the artcileCatalytic hydroconversion of Yiwu lignite over solid superacid and solid superbase, Category: esters-buliding-blocks, the main research area is lignite solid superacid superbase catalytic hydroconversion.

Trifluoromethanesulfonic acid supported on attapulgite powder (TFMSA/AP) and Mg2Si/γ-Al2O3 were facilely prepared by impregnating TFMSA onto AP and Mg2Si onto γ-Al2O3. The extraction residue from Yiwu lignite (YLER) was subjected to non-catalytic hydroconversion (NCHC) and catalytic hydroconversion (CHC) over TFMSA/AP and Mg2Si/γ-Al2O3, resp. Detailed mol. compositions of the soluble portions from the NCHC (SPNCHC) and CHC over TFMSA/AP (SPCHC-A) and Mg2Si/γ-Al2O3 (SPCHC-B) were characterized with a gas chromatograph/mass spectrometer. As a result, the yields of SPCHC-A and SPCHC-B are 19.6% and 17.5%, resp., which are much higher than that of SPNCHC (1.04%), suggesting that both TFMSA/AP and Mg2Si/γ-Al2O3 show excellent activity for the CHC of YLER. Arenes and arenols are predominant in SPCHC-A and SPCHC-B, resp., while large amounts of alkanoates were detected in SPNCHC. The results indicate that TFMSA/AP effectively catalyzes the cleavage of Car-Calk and Calk-O bridged bonds (BBs) in YLER, while Mg2Si/γ-Al2O3 significantly promotes the cleavage of C-O BBs in YLER. Di(1-naphthyl)methane, 1-methylnaphthalene, oxydibenzene, and benzyloxybenzene were used as coal-related model compounds (CRMCs) for the CHC to further explore the catalysis of TFMSA/AP and Mg2Si/γ-Al2O3. The results show that TFMSA/AP not only releases mobile H+ but also heterolytically splits H2 to form an immobile H- and a mobile H+, leading to the cleavage of Calk-Car and Calk-O BBs in the CRMCs. In contrast, Mg2Si/γ-Al2O3 facilitates heterolytically splitting H2 to an immobile H+ and a mobile H-, resulting in the cleavage of C-O BBs in the CRMCs.

Fuel published new progress about Catalysts. 123-29-5 belongs to class esters-buliding-blocks, name is Ethyl nonanoate, and the molecular formula is C11H22O2, Category: esters-buliding-blocks.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Ghahremani, Milad published the artcileA Theoretical Analysis on a Multi-Bed Pervaporation Membrane Reactor during Levulinic Acid Esterification Using the Computational Fluid Dynamic Method, SDS of cas: 539-88-8, the main research area is multi bed pervaporation membrane reactor levulinic acid esterification; computational fluid dynamic method; computational fluid dynamic (CFD) method; esterification process; modeling and simulation; pervaporation membrane reactor.

Pervaporation is a peculiar membrane separation process, which is considered for integration with a variety of reactions in promising new applications. Pervaporation membrane reactors have some specific uses in sustainable chem., such as the esterification processes. This theor. study based on the computational fluid dynamics method aims to evaluate the performance of a multi-bed pervaporation membrane reactor (including poly (vinyl alc.) membrane) to produce Et levulinate as a significant fuel additive, coming from the esterification of levulinic acid. For comparison, an equivalent multi-bed traditional reactor is also studied at the same operating conditions of the aforementioned pervaporation membrane reactor. A computational fluid dynamics model was developed and validated by exptl. literature data. The effects of reaction temperature, catalyst loading, feed molar ratio, and feed flow rate on the reactor’s performance in terms of levulinic acid conversion and water removal were hence studied. The simulations indicated that the multi-bed pervaporation membrane reactor results to be the best solution over the multi-bed traditional reactor, presenting the best simulation results at 343 K, 2 bar, catalyst loading 8.6 g, feed flow rate 7 mm3/s, and feed molar ratio 3 with levulinic acid conversion equal to 95.3% and 91.1% water removal.

Membranes (Basel, Switzerland) published new progress about Catalysts. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, SDS of cas: 539-88-8.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Han, Wen-Tao published the artcileInter-integration reactive distillation with vapor permeation for ethyl levulinate production: Equipment development and experimental validating, Computed Properties of 539-88-8, the main research area is inter integration reactive distillation vapor permeation ethyl levulinate production.

Et levulinate, one of the main derivatives of levulinic acid (LA), is of significant potential as platform chems. for bio-based materials. The esterification of LA was generally carried out in a conventional batch reactor or in a conventional reactive distillation column. However, traditional methods are hard to deal with equilibrium limited reactions and azeotropic issues. Therefore, the inter-integration reactive distillation with vapor permeation (R-VP-D) process, which integrated reaction, vapor permeation, and distillation into one single unit, is proposed in this paper and validated in the pilot-scale experiments A comparative study is made between a pilot-scale RD column with and without VP module. Owing to the water-selective VP membrane and the ingenious design of related apparatuses, the R-VP-D process reveal a superiority in LA conversion of 21.9% maximum higher than RD without VP process and removing of product water about 53.6% from VP module, which indicates its promising industrial application in process intensification field.

AIChE Journal published new progress about Catalysts. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Computed Properties of 539-88-8.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Shao, Yuewen published the artcileCooperation between hydrogenation and acidic sites in Cu-based catalyst for selective conversion of furfural to γ-valerolactone, Category: esters-buliding-blocks, the main research area is copper catalyst furfural gamma valerolactone cooperation hydrogenation.

The production of γ-valerolactone (GVL) receives increasing attention due to its extensive applications as a promising fuel and fuel additive. In this study, the direct conversion of biomass-derived furfural to GVL with a unprecedent yield of 90.5% was achieved via consecutive hydrogenation and acid-catalyzed reactions over CuAl for hydrogenation and a co-catalyst (i.e. H-ZSM-5) for acid-catalysis in ethanol. The relative abundance of the hydrogenation sites and acidic sites determines the reaction network and the transfer of the main products from furfuryl alc. (FA) to Et levulinate (EL) or GVL, as the acidic sites, especially the Bronsted acidic sites, not only catalyze the formation of EL from FA, but also affect the hydrogenation activity of CuAl. However, the Lewis acidic sites facilitate the opening ring of FA to 1,4-pentanediol, preventing the GVL formation. The acid catalyst and hydrogenation catalyst deactivate via varied mechanisms in the conversion of furfural to GVL, which is required to be considered in the further development of the robust catalysts.

Fuel published new progress about Catalysts. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Category: esters-buliding-blocks.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Kumari, Nisha published the artcileNanoarchitectonics of sulfonated biochar from pine needles as catalyst for conversion of biomass derived chemicals to value added products, Safety of Ethyl 4-oxopentanoate, the main research area is sulfonated biochar catalyst fructose levulinic acid ethyl levulinate.

Utilizing waste lignocellulosic biomass to synthesize biofuel precursors constructs an important way to solve the current energy crisis. In this work, we have prepared a sulfonated acid catalyst from pine needles derived biochar using chlorosulfonic acid for conversion of fructose to levulinic acid and levulinic acid to Et levulinate. In the best optimized conditions, sulfonated biochar as a catalyst exhibited excellent catalytic activity for the fructose conversion to levulinic acid and its esterification to Et levulinate with yield 33% and 97%.

Catalysis Communications published new progress about Catalysts. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Safety of Ethyl 4-oxopentanoate.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Levi, Samuel M. published the artcileCatalytic activation of glycosyl phosphates for stereoselective coupling reactions, Recommanded Product: Benzyl acetate, the main research area is stereoselective coupling catalytic glycoside preparation nucleophilic substitution thiourea; H bonding; glycosylation; organocatalysis; phosphate.

Glycosyl phosphates are shown to be activated to stereospecific nucleophilic substitution reactions by precisely tailored bis-thiourea catalysts. Enhanced reactivity and scope is observed with phosphate relative to chloride leaving groups. Stronger binding (Km) to the H-bond donor and enhanced reactivity of the complex (kcat) enables efficient catalysis with broad functional group compatibility under mild, neutral conditions.

Proceedings of the National Academy of Sciences of the United States of America published new progress about Catalysis. 140-11-4 belongs to class esters-buliding-blocks, name is Benzyl acetate, and the molecular formula is C9H10O2, Recommanded Product: Benzyl acetate.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Kamel Ariffin, Maryam Farhana published the artcileFeCl3.6H2O Chitosan coated superparamagnetic nanoparticles supporting lipase enzyme from Candida Antarctica for microwave assisted biodiesel production, Recommanded Product: Methyl docosanoate, the main research area is Chitosan superparamagnetic nanoparticles microwave assisted biodiesel production.

Biocatalysis has emerged as a green technol. in chem. based catalysis. Immobilization of enzymes onto magnetized nanomaterials enhances downstream processing as it eases their separation from reaction mixture Synthesis of the nanoparticles was performed in an aqueous solution of FeCl3.6H2O as precursor and NH3 as nucleating agent under microwave irradiation The maghemite complex was crosslinked with glutaraldehyde to provide conducive environment for enzyme immobilization. Stability of produced immobilized lipases against different conditions were evaluated such as working temperatures from 27°C to 85°C and retained more than 64% of its activity at 85°C. The immobilized lipase complex was able to withstand a wide range of acidic to alk. environment from pH 5.5 to pH 9.5. The enzyme retains more than 59% of its activity after 14 days of storage and can be recycled for more than 7 cycles with remaining high activity at 93.7%. Developed enzyme was then subjected to microwave irradiation for transesterification of palm oil to produce biodiesel. Highest biodiesel recovery achieved from microwave assisted immobilized lipase catalyzed transesterification of palm oil was 70.2%. The phys. properties of produced biodiesel was evaluated and fulfilled the ASTM general requirement for fuels.

Renewable Energy published new progress about Catalysis. 929-77-1 belongs to class esters-buliding-blocks, name is Methyl docosanoate, and the molecular formula is C23H46O2, Recommanded Product: Methyl docosanoate.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Kim, Sehyun published the artcileIn Vitro and In Vivo Human Body Odor Analysis Method Using GO:PANI/ZNRs/ZIF-8 Adsorbent Followed by GC/MS, SDS of cas: 6259-76-3, the main research area is graphene oxide polyaniline zinc nanorod ZIF 8 body odor; GO:PANI/ZNRs/ZIF−8; headspace-in needle microextraction; human body odor; needle-based adsorbent; response surface methodology; volatile organic compounds.

Among various volatile organic compounds (VOCs) emitted from human skin, trans-2-nonenal, benzothiazole, hexyl salicylate, α-hexyl cinnamaldehyde, and iso-Pr palmitate are key indicators associated with the degrees of aging. In our study, extraction and determination methods of human body odor are newly developed using headspace-in needle microextraction (HS-INME). The adsorbent was synthesized with graphene oxide:polyaniline/zinc nanorods/zeolitic imidazolate framework-8 (GO:PANI/ZNRs/ZIF-8). Then, a wire coated with the adsorbent was placed into the adsorption kit to be directly exposed to human skin as in vivo sampling and inserted into the needle so that it was able to be desorbed at the GC injector. The adsorption kit was made inhouse with a 3D printer. For the in vitro method, the wire coated with the adsorbent was inserted into the needle and exposed to the headspace of the vial. When a cotton T-shirt containing body odor was transferred to a vial, the headspace of the vial was saturated with body odor VOCs. After volatile organic compounds were adsorbed in the dynamic mode, the needle was transferred to the injector for anal. of the volatile organic compounds by gas chromatog./mass spectrometry (GC/MS). The conditions of adsorbent fabrication and extraction for body odor compounds were optimized by response surface methodol. (RSM). In conclusion, it was able to synthesize GO:PANI/ZNRs/ZIF-8 at the optimal condition and applicable to both in vivo and in vitro methods for body odor VOCs anal.

Molecules published new progress about Body odor. 6259-76-3 belongs to class esters-buliding-blocks, name is Hexyl 2-hydroxybenzoate, and the molecular formula is C13H18O3, SDS of cas: 6259-76-3.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics