Lipozyme 435-Mediated Synthesis of Xylose Oleate in Methyl Ethyl Ketone

In this paper, we have performed the Lipozyme 435-catalyzed synthesis of xylose oleate in methyl ethyl ketone (MEK) from xylose and oleic acid. The effects of substrates’ molar ratios, reaction temperature, reaction time on esterification rates, and Lipozyme 435 reuse were studied. Results showed that an excess of oleic acid (xylose: oleic acid molar ratio of 1:5) significantly favored the reaction, yielding 98% of xylose conversion and 31% oleic acid conversion after 24 h-reaction (mainly to xylose mono- and dioleate, as confirmed by mass spectrometry). The highest Lipozyme 435 activities occurred between 55 and 70 °C. The predicted Ping Pong Bi Bi kinetic model fitted very well to the experimental data and there was no evidence of inhibitions in the range assessed. The reaction product was purified and presented an emulsion capacity close to that of a commercial sugar ester detergent. Finally, the repeated use of Lipozyme 435 showed a reduction in the reaction yields (by 48 and 19% in the xylose and oleic acid conversions, respectively), after ten 12 h-cycles.

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Kinetic Study on Esterification of Ascorbyl Oleate Catalyzed by Lipase NS 88011

Biointerface Research in Applied Chemistry ◽

10.33263/briac111.83748388 ◽

2020 ◽

Vol 11 (1) ◽

pp. 8374-8388

Keyword(s):

Experimental Data ◽

Ascorbic Acid ◽

Oleic Acid ◽

Reaction Mechanism ◽

Vitamin C ◽

Kinetic Study ◽

Immobilized Enzyme ◽

Molar Ratio ◽

A Value ◽

Ping Pong

In this study, bisubstrate kinetics mechanism models were correlated with the experimental data of ascorbyl oleate using the new lipase preparation, Candida antarctica NS 88011, and kinetic parameters (Vmax, Km, and Ki) were estimated. The highest conversion (49.42 %) was observed at 1 h of reaction using the ascorbic acid/oleic acid molar ratio of 1:9, 70 ºC and 30 % of enzymatic loading. The Ping Pong Bi-Bi model showed better congruence with the experimental data for all the effects evaluated. The kinetic constants showed that the lipase had an identical affinity, with a value of 0.81 for both substrates and inhibitory constant (Ki) of ascorbic acid (1.959) much higher than oleic acid (0.0008). It has been demonstrated that lipase has good operational stability (14th cycle). The results obtained with the new immobilized enzyme are valuable to elucidate the reaction mechanism. In addition, it represents an important contribution to optimize the reaction and create strategies to increase the productivity of the esters of vitamin C.

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Metals on ZrO2: Catalysts for the Aldol Condensation of Methyl Ethyl Ketone (MEK) to C8 Ketones

Catalysts ◽

10.3390/catal8120622 ◽

2018 ◽

Vol 8 (12) ◽

pp. 622 ◽

Cited By ~ 3

Author(s):

Zahraa Al-Auda ◽

Hayder Al-Atabi ◽

Keith Hohn

Keyword(s):

Methyl Ethyl Ketone ◽

Main Product ◽

Aldol Condensation ◽

Fixed Bed ◽

Hydrogenation Reaction ◽

Fixed Bed Reactor ◽

Molar Ratio ◽

Phase Reaction ◽

Methyl Ethyl ◽

One Step

Methyl ethyl ketone (MEK) was converted to heavier ketones in one step, using a multi-functional catalyst having both aldol condensation (aldolization and dehydration) and hydrogenation properties. 15% Cu supported zirconia (ZrO2) was investigated in the catalytic gas phase reaction of MEK in a fixed bed reactor. The results showed that the main product was 5-methyl-3-heptanone (C8 ketone), with side products including 5-methyl-3-heptanol, 2-butanol, and other heavy products (C12 and up). The effects of various reaction parameters, like temperature and molar ratio of reactants (H2/MEK), on the overall product selectivity were studied. It was found that with increasing the temperature of the reaction, the selectivity to the C8 ketone increased, while selectivity to the 2-butanol decreased. Also, hydrogen pressure played a significant role in the selectivity of the products. It was observed that with increasing the H2/MEK molar ratio, the 2-butanol selectivity increased because of the hydrogenation reaction, while decreasing this ratio led to increasing the aldol condensation products. In addition, it was noted that both the conversion and selectivity to the main product increased using a low loading percentage of copper, 1% Cu–ZrO2. The highest selectivity of 5-methyl-3-heptanone reached ~64%, and was obtained at a temperature of around 180 °C and a molar ratio of H2/MEK equal to 2. Other metals (Ni, Pd, and Pt) that were supported on ZrO2 also produced 5-methyl-3-heptanone as the main product, with slight differences in selectivity, suggesting that a hydrogenation catalyst is important for producing the C8 ketone, but that the exact identity of the metal is less important.

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Continuous Catalyst-Free Esterification of Oleic Acid in Compressed Ethanol

International Journal of Chemical Engineering ◽

10.1155/2014/803783 ◽

2014 ◽

Vol 2014 ◽

pp. 1-5 ◽

Cited By ~ 8

Author(s):

Ana Carolina de Araujo Abdala ◽

Vitor Augusto dos Santos Garcia ◽

Caroline Portilho Trentini ◽

Lúcio Cardozo Filho ◽

Edson Antonio da Silva ◽

...

Keyword(s):

Oleic Acid ◽

Residence Time ◽

Tubular Reactor ◽

Reaction Medium ◽

Ethyl Esters ◽

Molar Ratio ◽

Molar Ratios ◽

Catalyst Free ◽

Free Process ◽

Positive Effect

The esterification of oleic acid in a continuous catalyst-free process using compressed ethanol was investigated in the present study. Experiments were performed in a tubular reactor and variables investigated were temperature, pressure, and oleic acid to ethanol molar ratio for different residence time. Results demonstrated that temperature, in the range of 473 K to 573 K, and pressure had a positive effect on fatty acid ethyl esters (FAEE) production. In the experimental range investigated, high conversions can be obtained at low ethanol concentrations in the reaction medium and it was observed that oleic acid to ethanol molar ratios greater than 1 : 6 show no significant increase in conversion. Nonnegligible reaction conversions (>90%) were achieved at 573 K, 20 MPa, oleic acid to ethanol molar ratio of 1 : 6, and 20 minutes of residence time.

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DOPE–oleic acid–Ca2+ as DNA condensing agent

European Pharmaceutical Journal ◽

10.2478/afpuc-2018-0001 ◽

2018 ◽

Vol 65 (1) ◽

pp. 1-9

Author(s):

D. Galliková ◽

G. Liskayová ◽

A. Búcsi ◽

L. Hubčík ◽

J.C. Martínez ◽

...

Keyword(s):

Oleic Acid ◽

Binding Capacity ◽

Hexagonal Phase ◽

Dna Delivery ◽

Lattice Parameter ◽

Molar Ratio ◽

X Ray Diffraction ◽

Time Intervals ◽

Molar Ratios ◽

Dominant Structure

Abstract Phospholipid-based non-viral carriers composed of neutral phospholipid dioleoylphosphatidylethanolamine (DOPE) and the binary mixture DOPE–oleic acid (OA) are examined as potential DNA delivery vectors. The process of DNA condensation in the presence of Ca2+ ions has been monitored through changes in emmision intensity of fluorescent probe ethidium bromide. The decline in fluorescence intensity with increasing Ca2+ concentration at two different time intervals was correlated with the binding capacity of complexes and possible release of DNA from the complex. The microstructure of DOPE–OA mixtures at different OA/DOPE molar ratios and that of DOPE–OA–DNA–Ca2+ complexes were determined using synchrotron small angle X-ray diffraction (SAXD). We identified inverted hexagonal phase HII as the dominant structure. OA affects the lattice parameter of HII formed by DOPE. With the increasing OA/DOPE molar ratio, the lattice parameter decreases, which results in significantly lower fraction of DNA bound to the OA-enriched complexes.

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REAKSI KATALITIS ESTERIFIKASI ASAM OLEAT DAN METANOL MENJADI BIODIESEL DENGAN METODE DISTILASI REAKTIF

REAKTOR ◽

10.14710/reaktor.12.2.78-82 ◽

2008 ◽

Vol 12 (2) ◽

pp. 78 ◽

Cited By ~ 1

Author(s):

Kusmiyati Kusmiyati

Keyword(s):

Oleic Acid ◽

Reactive Distillation ◽

Reaction Times ◽

Biodiesel Production ◽

Molar Ratio ◽

Molar Ratios ◽

Animal Fats ◽

Alternative Diesel Fuel ◽

Result Show ◽

American Standard

Biodiesel is an alternative diesel fuel that is produced from vegetable oils and animal fats. Generally, it is formed by trans etherification reaction of triglycerides in the vegetable oil or animal fat with an alcohol. In this work, etherification reaction was carried out using oleic acid, methanol and sulphuric acid as a catalyst by reactive distillation method. In order to determine the best conditions for biodiesel production by reactive distillation, the experiments were carried out at different temperature (1000C, 1200C, 1500C and 1800C) using methanol/oleic acid molar ratios (1:1, 5:1, 6:1, 7:1, 8:1), catalyst/ oleic acid molar ratios (0.5%wt, 1%wt, 1.5%wt and 2%wt) and reaction times (15, 30, 45, 60, 75 and 90 minutes). Result show that at temperature 1800C, methanol/oleic acid molar ratio of 8:1, amount of catalyst 1% for 90 minute reaction time gives the highest conversion of oleic acid above 0.9581. Biodiesel product from oleic acid was analyzed by ASTM (American Standard for Testing Material). The results show that the biodiesel produced has the quality required to be a diesel substitute. Biodiesel merupakan salah satu bahan bakar alternatif pengganti bahan bakar fosil yang diproduksi dari bahan baku minyak nabati dan lemak hewan. Secara umum biodiesel diproduksi melalui reaksi transesterifikasi minyak nabati atau lemak hewan dan alkohol. Pada penelitian ini proses esterifikasi pada pembuatan biodiesel menggunakan bahan baku asam oleat murni (99%), metanol dan katalis asam sulfat dengan metode distilasi reaktif. Distilasi reaktif merupakan penggabungan antara proses reaksi dan proses pemisahan dalam satu unit proses sehingga memungkinkan diperoleh biodiesel dengan kemurnian yang tinggi. Variabel yang dipelajari pada penelitian ini adalah temperatur (1000C, 1200C, 1500C, 1800C), jumlah katalis H2SO4 (0,5% berat, 1% berat, 1,5% berat, 2% berat), rasio metanol : asam oleat dinyatakan 1:1, 5:1, 6:1, 7:1, 8:1 (dalam % berat) terhadap konversi asam oleat serta. Berdasarkan hasil penelitian, konversi maksimum yang dapat dicapai sebesar 0,9581 pada kondisi reaksi berat katalis H2SO4 1% berat, rasio metanol:asam oleat 8:1 dan suhu reaksi 1800C. Berdasarkan hasil analisa ASTM, biodiesel yang diperoleh memenuhi standar bahan bakar cair dan dapat digunakan sebagai bahan bakar pengganti petroleum diesel.

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CATALYSTS OF OXIDATION REACTION OF BUTENE-1 TO METHYLETHYLKETONE

IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA ◽

10.6060/tcct.20186102.5693 ◽

2018 ◽

Vol 61 (2) ◽

pp. 53

Author(s):

Minira M. Agaguseynova ◽

Gunel I. Amanullayeva ◽

Zehra E. Bayramova

Keyword(s):

Binary System ◽

Low Temperature ◽

Molecular Oxygen ◽

Methyl Ethyl Ketone ◽

Oxidation Reaction ◽

Molar Ratio ◽

Palladium Chloride ◽

Methyl Ethyl ◽

Complex Catalyst ◽

Mild Conditions

The available and simple metal complex systems of catalytic oxidation of unsaturated hydrocarbons were developed. It is shown that these systems catalyze the selective liquid-phase oxidation of butene-1 to methyl ethyl ketone by molecular oxygen at low temperature. The best results were revealed using Cu(I)Cl monovalent chloride. The catalyst for the production of methylethylketone is a binary system containing complexes of copper and palladium chloride at a molar ratio of 2:1. Hexamethylphosphoramide is used as the ligand and palladium chloride complex as an additional complex contains benzonitrile. A combined catalyst has been offered. It allows to carry out the oxidation reaction of butene to methyl ethyl ketone under mild conditions (low temperature, atmospheric pressure) with high selectivity and yield of the desired product. The proposed binary system is able to coordinate molecular oxygen and butene-1, and thus it becomes possible to conduct the oxidation reaction not directly between butene-1 and O2, and using a specific complex catalyst system allowing them to react with each other in an activated coordinated state. Absorption properties of catalysts synthesized on the bases of transition metals have been studied and activation of molecular oxygen and butane-1 has been determined. As a result of interaction of coordinated oxygen and butane-1 it is possible to carry out oxidation reaction to methylethylketone in mild condition. The specific feature of the offered binary catalyst is irreversible absorption of molecular oxygen. Mild conditions of the reaction proceeding decreases considerably amount of by-products and simplify obtaining and separation of the main product-methylethylketone. Due to the fact that the absorption of O2 is irreversible and it is possible to easily remove the excess amount of O2 after the formation of the oxygen complex. The developed method has the advantage from the point of view of safety.Forcitation:Agaguseynova M.M., Amanullayeva G.I., Bayramova Z.E. Catalysts of oxidation reaction of butene-1 to methylethylketone. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 2. P. 53-57

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