Silica Coating of Metal-Loaded H-ZSM-22 to Form the Core-Shell Nanostructures: Characterization, Textural Properties, and Catalytic Potency in the Esterification of Oleic Acid

In this study, ZSM-22 was synthesized using N,N-diethylaniline as a template through a hydrothermal method. The proton and various metals such as zirconium, strontium, and iron were immobilized on the surface of obtained zeolites through the ion exchange method. The catalysts were studied by Fourier-Transform Infrared Spectroscopy (FT-IR), X-Ray Diffraction (XRD), Brunauer–Emmett–Teller (BET) adsorption isotherms, Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM), Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) elemental analysis, and Temperature-Programmed Desorption of ammonia (TPD-NH3) technique for determining the number of acid sites. In the esterification reaction of oleic acid, the operating conditions such as catalyst dosage, temperature, molar ratio of methanol to oil, and reaction time were optimized and adjusted at 11 wt%, 70°C, 10 : 1, and 48 h subsequently. The maximum yield% of 48.07% was achieved in the presence of Zr-H-ZSM-22 at optimum conditions. In order to improve the efficiency of three zeolites Zr-H-ZSM-22, Fe-H-ZSM-22, and Sr-H-ZSM-22, the core-shell structures with SiO2 coating were prepared. Zr-H-ZSM-22@SiO2 was less active than Zr-H-ZSM-22 due to the SiO2 coverage of Lewis active sites.

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Medicated structural PVP/PEG composites fabricated using coaxial electrospinning

e-Polymers ◽

10.1515/epoly-2016-0244 ◽

2017 ◽

Vol 17 (1) ◽

pp. 39-44 ◽

Cited By ~ 8

Author(s):

Yong-Hui Wu ◽

Deng-Guang Yu ◽

Hai-Peng Li ◽

Xiang-Yang Wu ◽

Xiao-Yan Li

Keyword(s):

Electron Microscope ◽

Citric Acid ◽

Shell Structure ◽

Water Soluble ◽

Working Fluid ◽

Coaxial Electrospinning ◽

Core Shell ◽

The Core ◽

Poorly Water Soluble ◽

Core Shell Structure

AbstractA new type of medicated polymeric composite consisting of acyclovir (ACY), polyvinylpyrrolidone K60 (PVP) and polyethylene glycol 6000 (PEG) with core-shell structure were prepared by a coaxial electrospinning process. The composites could enhance the dissolution of the poorly water-soluble drug. The shell layers were formed from a spinnable working fluid containing the filament-forming PVP and citric acid while the core parts were prepared from an un-spinnable co-dissolving solution composed of ACY, sodium hydrate and PEG. Scanning electron microscope and transmission electron microscope observations demonstrated that the composites had a homogeneous linear topography with a slippery surface, a diameter of 670±130 nm, and an obvious core-shell structure. X-ray diffraction (XRD) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy results demonstrated that the drug and citric acid contained in the core and shell parts were in an amorphous status. In vitro dissolution experiments exhibited that ACY was able to be free within 1 min, and the dissolution media were neutral due to acid-basic action within the core-shell structures. The medicated nanocomposites resulted from a combined usage of hydrophilic polymeric excipients PVP and PEG could provide a new solution to the problem associated with the dissolution of poorly water-soluble drugs.

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Synthesis of Core-Shell Composite of Conductive Polymeric Materials onto Silica Using Supercritical Carbon Dioxide

MRS Advances ◽

10.1557/adv.2020.201 ◽

2020 ◽

Vol 5 (40-41) ◽

pp. 2121-2127

Author(s):

Ssu-Hao Huang ◽

Pei-Hua Chen ◽

Yan-Ping Chen ◽

Muoi Tang

Keyword(s):

Carbon Dioxide ◽

Supercritical Carbon Dioxide ◽

Polymeric Materials ◽

Optimal Operation ◽

Molar Ratio ◽

Core Shell ◽

The Core ◽

Operation Conditions ◽

Shell Composite ◽

Supercritical Carbon

ABSTRACTThe polymerization of 3,4-ethylenedioxythiophene (EDOT) onto nanosilica (SiO2) was synthesized in this study by using supercritical carbon dioxide (SCCO2). With the addition of dopants of p-toluenesulfonic acid (p-TSA) or decylbenzene sulfonic acid (DBSA), the PEDOT/SiO2 composite became conductive. The product was characterized by FTIR spectroscopy and the core-shell structure was confirmed through the TEM images. The electrical properties were analyzed by UV-vis absorbance and four-point probe measurement. DBSA is shown as the better dopants with the molar ratio (DBSA/EDOT) of 0.2 at the reaction time of 48 hours. The maximum coating percentage is 63 wt% under the optimal operation conditions at 40oC and 280 bar. The conductivity is tuned up to 6.6×10-2 S/cm after the coating process.

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A Novel Route for Conversion of Free Fatty Acids in Acidic Oils to Methyl Esters by In-Situ Hydrolysis of Methyl Acetate

International Journal of Chemical Reactor Engineering ◽

10.1515/1542-6580.2493 ◽

2011 ◽

Vol 9 (1) ◽

Author(s):

Vijaya Lakshmi Ch ◽

Uday Bhaskar R.V.S ◽

Viswanath Kotra ◽

Satyavathi Bankupalli

Keyword(s):

Fatty Acids ◽

Free Fatty Acids ◽

Methyl Acetate ◽

Edible Oils ◽

Methyl Esters ◽

Maximum Yield ◽

Molar Ratio ◽

Esterification Reaction ◽

Higher Alcohol

Biodiesel from clean oils is comparatively easier than production from crude and non-edible oils. To achieve maximum yield of biodiesel, a two stage process is adopted in which non-edible oils are used as feed-stock: an acid catalyzed esterification of free fatty acids followed by base catalyzed transesterification. Presence of water formed during esterification reaction is detrimental to a viable transesterification process. In the present work, an alternate method for removal of water by in situ hydrolysis reaction of methyl acetate is introduced. The dehydration using methyl acetate during esterification has yielded good results as the soap formed during transesterification was minimal. The results indicated high conversion of triglycerides to methyl ester for lower oil to methanol ratio and at a lower temperature. For 1:3 molar ratio of oil to methanol, the conversion obtained was less than 90 percent and is equivalent to conversions with higher alcohol ratios during esterification in the absence of methyl acetate. These results are indicative of the fact that use of methyl acetate reduces the alcohol to oil ratio without affecting the conversions. Moreover, higher conversions are possible at lower temperatures in the presence of methyl acetate. It is further observed that the oils that are subjected to free fatty acid conversions in the presence of methyl acetate record very little soap formation during the transesterification reactions, thereby resulting in higher grade of biodiesel.

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Performance Study of Pervaporation Reactor (PVR) for Esterification of Acetic Acid with Ethanol

International Journal of Chemical Reactor Engineering ◽

10.2202/1542-6580.2025 ◽

2010 ◽

Vol 8 (1) ◽

Author(s):

Kailas L. Wasewar ◽

Shyambabu Patidar ◽

Vijay K. Agarwal ◽

Ajit Rathod ◽

Shriram S. Sonawane ◽

...

Keyword(s):

Acetic Acid ◽

Catalyst Concentration ◽

Reaction System ◽

Operating Conditions ◽

Molar Ratio ◽

Optimum Operating ◽

Esterification Reaction ◽

Reactant Ratio ◽

Performance Study ◽

Membrane Area

The most common reaction system studied for the application of pervaporation (PV) is an esterification reaction between alcohol and acid in the presence of a catalyst. In present paper, performance of pervaporation reactor (PVR) for esterification of acetic acid with ethanol was studied. Model equations were developed for reaction and separation in PVR. Model results were validated with experimental results and excellent comparison was obtained. The effect of various parameters such as: reactant ratio, ratio of effective membrane area to volume of reacting mixture, catalyst concentration and flux on the performance of PVR were discussed. The optimum conditions were obtained as: membrane area to volume of reacting mixture = 2 m-1, reactant ratio = 1.5, catalyst concentration = 50 g/l for esterification of acetic acid with ethanol in PVR. The model presented can also be used for the other esterification reactions. The described model allows the evolution of the reaction time necessary to achieve a given conversion. The process parameters: temperature, catalyst concentration, initial molar ratio of acid to alcohol, the ratio of the effective membrane area to the volume of reacting mixture can be changed in order to attain the optimum operating conditions of the pervaporation-esterification coupling operating.

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The green, ultrafine cellulose-based porous nanofibrous membranes for efficient heavy metal ion removal through incorporation of chitosan by various electrospinning ways

10.21203/rs.3.rs-1215365/v1 ◽

2022 ◽

Author(s):

Qiushi Li ◽

Ganmao Su ◽

Ronggang Luo ◽

Guanben Du ◽

Linkun Xie ◽

...

Keyword(s):

Heavy Metal ◽

Active Sites ◽

Metal Removal ◽

Copper Ions ◽

Core Shell ◽

Adsorption Effect ◽

Adsorption Sites ◽

Adsorption Performance ◽

The Core ◽

Nanofibrous Membranes

Abstract The rapid global industrialization worsens the contamination of heavy metals in aquatic ecosystems on the earth. In this study, the green, ultrafine cellulose-based porous nanofibrous membranes for efficient heavy metal removal through incorporation of chitosan by the conventional and core-shell electrospinning ways were firstly obtained. The relations among parameters of electrospun solution, micro-morphology and porosity for nanofibers, the variation of chemical active sites and adsorption performance of biocomposite nanofibrous membranes for conventional and core-shell electrospinning as well as the adsorption effect factors of copper ions including initial concentration, pH of solution and interaction time were comprehensively investigated. The results show that the average diameter for conventional and core-shell ultrafine nanofibers at 50% chitosan and 30% chitosan loading can achieve 56.22 nm and 37.28 nm, respectively. The core-shell cellulose acetate/chitosan (CA/CS) biocomposite nanofibrous membranes induced the surface aggregation of copper ions to impede the further adsorption. The more uniform distribution for chemical adsorption sites can be obtained by the conventional single-nozzle electrospinning than by the core-shell one, which promotes the adsorption performance of copper ions and decreases the surface shrinkage of nanofibrous membranes during adsorption. The 30% CS conventional nanofibrous membranes at the pH=5 aqueous solution showed the optimum adsorption capacity of copper ions (86.4 mg/g). The smart combination of renewable biomass with effective chemical adsorptive sites, the electrospinning technology with interwoven porous structure and the adsorption method with low cost and facile operation shows a promising prospect for water treatment.

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Synthesis of Magnetic Catalyst Derived from Oil Palm Empty Fruit Bunch for Esterification of Oleic Acid: An Optimization Study

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.17.1.12392.65-77 ◽

2021 ◽

Vol 17 (1) ◽

pp. 65-77

Author(s):

Shamala Gowri Krishnan ◽

Fei-Ling Pua ◽

Ee-Sann Tan

Keyword(s):

Oleic Acid ◽

Oil Palm ◽

Acid Catalyst ◽

Catalytic Performance ◽

Molar Ratio ◽

Esterification Reaction ◽

Empty Fruit Bunch ◽

Biomass Waste ◽

Magnetic Catalyst ◽

Rsm Optimization

Biomass, renewable, abundantly available and a good source of energy. The conversion of biomass waste into valuable products has received wide attention. In this study, an empty fruit bunch (oil palm EFB) supported magnetic acid catalyst for esterification reaction was successfully prepared via the one-step impregnation process. The new magnetic catalyst achieved a higher surface area of 188.87 m2/g with a total acidity of 2.4 mmol/g and identified iron oxide as g-Fe2O3. The magnetization value of 24.97 emu/g demonstrated that the superparamagnetic catalyst could be easily recovered and separated after the reaction using an external magnet. The catalytic performance of oil palm EFB supported magnetic acid catalyst was examined by esterification of oleic acid. Esterification process parameters were optimized via Response Surface Methodology (RSM) optimization tool with Box-Behnken design (BBD). The following optimum parameters were determined: an amount of 9 wt% catalyst, molar ratio of methanol to oleic acid of 12:1, reaction time of 2 h and reaction temperature of 60 °C with a maximum conversion of 94.91% was achieved. The catalyst can be recycled up to five cycles with minimal loss in its activity. The oil palm waste-based magnetic acid catalyst indicates its potential replacement to the existing solid catalysts that are economical and environmentally friendly for the esterification process in biofuel applications. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

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Deactivation by sintering of the cobalt catalyst during the Fischer-Tropsch reaction

Journal of Mechanical Engineering Research ◽

10.30564/jmer.v2i1.277 ◽

2019 ◽

Vol 2 (1) ◽

Author(s):

Dounia Alihellal ◽

Lemnouer Chibane ◽

Mohamed El-Amine Slimani

Keyword(s):

Numerical Simulation ◽

Mathematical Model ◽

Active Sites ◽

Cobalt Catalyst ◽

Reaction Rates ◽

Operating Conditions ◽

Molar Ratio ◽

Fischer Tropsch ◽

Simulation Results ◽

By Products

In the present work, the deactivation by sintering of cobalt-based catalyst during Fischer-Tropsch synthesis at low temperature was studied by numerical simulation. For this purpose, a mathematical model was developed. The obtained simulation results allowed us to highlight and improve the understanding of the deactivation phenomena of cobalt-based Fischer-Tropsch catalysts by sintering. The main results also show that the sintering phenomenon is strongly dependent on the operating conditions, in particular, the temperature, the pressure, and the H2/CO molar ratio, as well as the reaction by-products such as water. The results obtained can, therefore, be used to understand more the sintering mechanism which may be linked to the change in the concentration of the active sites and the reaction rates.

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Synthesis of palm oil based polymeric ester through cationic addition polymerisation method

Malaysian Journal of Fundamental and Applied Sciences ◽

10.11113/mjfas.v17n1.1524 ◽

2021 ◽

Vol 17 (1) ◽

pp. 16-19

Author(s):

Yan Irawan ◽

Ika Juliana ◽

Emil Budianto

Keyword(s):

Oleic Acid ◽

Palm Oil ◽

Methyl Esters ◽

Initial Step ◽

Molar Ratio ◽

Polymeric Surfactant ◽

Esterification Reaction ◽

H Nmr ◽

Reaction Conversion ◽

Distribution Type

In this study, the synthesis of palm oil-based polymeric ester for application as a polymeric surfactant was carried out by a cationic addition polymerisation method through two steps. The initial step is a synthesis of fatty acid methyl esters oleate (FAMEO) through esterification reaction between oleic acid and methanol. The optimum conditions of the esterification reaction were carried out at a temperature of 70–80oC for 4 hours with the addition of 1wt% sulfuric acid as a catalyst. The molar ratio between oleic acid and methanol was 1:3. FAMEO was analysed using GCMS to determine the methyl ester content. The second step is the polymerisation of FAMEO. The polymerisation reaction of FAMEO was carried out at 120, 140, and 160oC with 1wt%, 3wt% and 5wt% of boron trifluoride dihydrate as a catalyst and an initiator of polymerisation reaction for 4 to 24 hours of reaction. The reaction conversion of the product was 66%. The polymeric ester was analysed H-NMR. Meanwhile, the molecular weight of that product was 1714 g/mol which analysed using GPC and the PDI was 1.12346 or equal to 1.12. It means that the polymerisation technique was controlled or living polymerisation, which indicates that the distribution type of this product was narrow monodisperse.

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Value-Added Processing of Lactose: Preparation of Bioactive Lactobionic Acid Using a Novel Catalytic Method

International Journal of Chemical Reactor Engineering ◽

10.2202/1542-6580.1530 ◽

2007 ◽

Vol 5 (1) ◽

Cited By ~ 2

Author(s):

Khaled Belkacemi ◽

Mirela Cristea Vlad ◽

Safia Hamoudi ◽

Joseph Arul

Keyword(s):

Active Sites ◽

Bimetallic Catalyst ◽

Batch Reactor ◽

Reaction Medium ◽

Value Added ◽

Operating Conditions ◽

Molar Ratio ◽

Catalytic Method ◽

Metals Loading ◽

Ph Range

The microaerial oxidation of an aqueous solution of lactose to lactonionic acid (LBA) over the heterogeneous bimetallic catalyst Bi-Pd supported on mesoporous SBA-15 material was carried out in an agitated semi-batch reactor in alkaline medium within the pH range of 7 to 9.The present work focused on the synthesis and characterization of the bimetallic catalyst as well as optimization of the reaction operating conditions. To this purpose, the effect of both active metals loading on the support, metal/lactose ratio, reaction pH and dissolved oxygen concentration on the oxidation performances was examined at a very mild temperature of 65 oC.The bimetallic catalyst 1.02%Pd, 0.64%Bi/SBA-15, (Bi/Pd molar ratio of 0.3) showed the highest activity (96 % lactose conversion) and 100 % selectivity towards the targeted LBA product. Furthermore, the formulated catalyst proved to be stable in the reaction medium as both metals leaching was insignificant. Based on XRD and XPS analyses, it is suggested that the metals constituting the bimetallic catalyst active sites assemble into an intermetallic alloy having Bi1.75Pd stoichiometry.

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