Esterification Reaction Of Acetic Acid Research Articles

Towards Photothermal Acid Catalysts Using Eco-Sustainable Sulfonated Carbon Nanoparticles—Part II: Thermal and Photothermal Catalysis of Biodiesel Synthesis

The main goal of this work is to evaluate the ability of sulfonated carbon nanoparticles (SCNs) to induce photothermal catalysis of the biodiesel synthesis reaction (transesterification of natural triglycerides (TGs) with alcohols). Carbon nanoparticles (CNs) are produced by the carbonization of cross-linked resin nanoparticles (RNs). The RNs are produced by condensation of a phenol (resorcinol or natural tannin) with formaldehyde under ammonia catalysis (Stober method). The method produces nanoparticles, which are carbonized into carbon nanoparticles (CNs). The illumination of CNs increases the temperature proportionally (linear) to the nanoparticle concentration and exposure time (with saturation). Solid acid catalysts are made by heating in concentrated sulfuric acid (SEAr sulfonation). The application of either light or a catalyst (SCNs) (at 25 °C) induced low conversions (<10%) for the esterification reaction of acetic acid with bioethanol. In contrast, the illumination of the reaction medium containing SCNs induced high conversions (>75%). In the case of biodiesel synthesis (transesterification of sunflower oil with bioethanol), conversions greater than 40% were observed only when light and the catalyst (SCNs) were applied simultaneously. Therefore, it is possible to use sulfonated carbon nanoparticles as photothermally activated catalysts for Fischer esterification and triglyceride transesterification (biodiesel synthesis).

Utilising magnetite and heteropoly acid to modify silica foam and consider catalytic activity for esterification and transesterification procedure

Silica foam can be helpful substrate to tailoring heterogenous catalyst in various shapes and size. In this work, we have successfully prepared and modified Silica Foam that modified by magnetite nanoparticle (FM) and heteropoly acid (FMH). These new composites were characterized by FT-IR, XRD, SEM, TGA, DTG, NH3-TPD, and VSM. The result confirms that fine dispersity of magnetite nano particle and heteropoly acid into silica foam and without any significant change in structure of materials. The synthesized composites FM and FMH were used as catalysts for the esterification reaction of acetic acid with five different alcohols and the transesterification reaction of sunflower, animal fats, and waste oils. The results show that the efficiency of the esterification reaction for the FMH catalyst is about 98.8 % and 78.8 % for the transesterification reaction.

Synthesis and characterization of NaY@ZIF‐8 composite by the ship‐in‐bottle method as a catalyst for esterification and transesterification reactions

AbstractZeolite imidazolate frameworks (ZIFs) were composited with NaY zeolite using two different approaches to the ship‐in‐bottle method. The two synthesized nanocatalysts showed that the ZIF‐8 composite with NaY zeolite could stabilize their structure as catalysts in an acidic environment. The NaY@ZIF‐8 nanocomposites that were prepared were investigated using Fourier transform infrared (FTIR), X‐ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), elemental mapping (MAP), thermogravimetric (TGA), temperature‐programmed desorption of ammonia (NH3‐TPD), and inductively coupled plasma analyses. The synthesized composites were used as catalysts for the esterification reaction of acetic acid with four different alcohols and the transesterification reaction of animal fats, vegetable oils, and waste oils. The results show that the efficiency of the esterification reactions for the two catalytic composites was 98.5% and 94.3%, respectively, and 78.1% for the transesterification reaction.

Kinetics of esterification of acetic acid with n‐butanol over different homogeneous acid catalysts

AbstractThe esterification reaction of n‐butanol and acetic acid has been performed in batch reactor in the presence of different homogeneous acid catalyst, namely sulfuric acid, nitric acid, and para toluene sulfonic acid (p‐TSA). The objective of present research work is to investigate kinetic behavior of esterification reaction over the temperature range of 60°C–80°C. The effect of reaction parameter such as catalyst loading varied from 1% to 5% v/v and acid to alcohol molar ratio of 1:1, 1:3, and 1:5 has been observed. A pseudo homogeneous kinetic model has been applied. Kinetic parameters such as equilibrium constant, reaction rate constant, enthalpy, activation energy, and entropy were calculated by the experimental data for different acid catalyst system. It was observed that sulfuric acid gives higher conversion 73% than p‐TSA 68.5% and nitric acid 66.25% at temperature of 80°C, 1:1 molar ratio and 3% catalyst concentration. The activation energy was estimated 36448.49, 23324.31 and 19060.156 J/mol K for three different catalyst sulfuric acid, nitric acid and p‐TSA respectively. The enthalpy and entropy of the esterification reaction of acetic acid with n‐butanol over three different catalysts has been calculated (Enthalpy: 25.788 KJ/mol, 12.256 KJ/mol, 28.320 KJ/mol, Entropy: 88.1 J/mol K, 45.298 J/mol K, 91.44 J/mol K) and found enthalpy is having positive value that shows reaction is endothermic.

Enhanced esterification performance by SO42−/ZrO2 anchored Nb2O5 nanotube

SO42-/ZrO2 anchored Nb2O5 nanotubes (SO42-/ZrO2@Nb2O5-NT) are prepared via the high temperature calcination, proton exchange, exfoliation, recombination, and impregnation processes. The structures and anchoring model can be confirmed by XRD, HRTEM, and FT-IR technologies. The acidic properties and specific surface area are characterized by NH3-TPD and N2 adsorption–desorption isotherms. The catalytic performances are evaluated via an esterification reaction of acetic acid and n-butanol. The results show that SO42-/ZrO2@Nb2O5-NT have stronger acid strength and higher acid content than that of Nb2O5-NT. The optimal esterification scheme is as follows: catalyst dosage is 11 wt.%, molar ratio of alcohol to acid is 2.7:1, reaction temperature is 118 ℃, and reaction time is 7 h. The esterification rate can be reached up to 92.31% over SO42-/ZrO2@Nb2O5-NT. We have rationalized esterification performance of these selected catalysts in light of structure–property relationships, which gives useful insight for the development and application of next generation esterification catalyst.

A new ZrC nano powder solid acid catalyst for the esterification synthesis of ethyl acetate

Zirconium carbide nano powder was synthesized and used as a new ceramic solid acid catalyst for esterification reaction of acetic acid. The catalytic active atoms and centers and the types of associated orbitals in Lewis acid catalytic reaction were determined based on calculated electronic band structure and partial electronic density of state (PEDOS) of ZrC. The conversion percentage of acetic acid to ethyl acetate was measured by the by titration of residual acetic acid. The ZrC has a very good performance as a solid acid catalyst in the conversion of acetic acid to ethyl acetate.

REACTION KINETICS OF ACETIC ACID WITH ETHANOL TO ETHYL ACETATE WITH SULFURIC ACID CATALYST

Ethyl acetate is an ester of ethanol and acetic acid. This compound is a colorless liquid with a characteristic odor. Ethyl acetate is widely used as a solvent because of its high solubility. The manufacture of ethyl acetate (ethyl ester) is referred to as the esterification process. This esterification reaction is an exothermic reaction, is reversible and generally runs very slowly so it requires a catalyst to obtain maximum ester. Domestic demand for ethyl acetate is increasing, while production in Indonesia is still lacking. Reactor design requires a reaction mechanism and kinetic data in the form of reaction rate equations and reaction rate constants. This study aims to determine the kinetics of the etherification of acetic acid presented in the form of the reaction rate equation, the value of the reaction rate constant, and the reaction equilibrium constant. In addition, this research also studied how the influence of sulfuric acid catalyst on the reaction rate constant and the reaction balance. The esterification reaction was carried out in a batch reactor. 99% acetic acid and H2SO4 catalyst whose concentrations are varied, are mixed in a reactor equipped with a magnetic stirrer which is operated at 400 rpm, then 96% ethanol is poured with a volume ratio of 1:1 to acetic acid, 5 mL of sample is taken to analyze the remaining acid after The reaction takes place, every certain time interval a sample is taken to be analyzed until an equilibrium point is obtained. From the results of this study it can be concluded that the esterification reaction of acetic acid with ethanol to produce ethyl acetate is a second order reaction with the reaction rate equation (-rA) = k1CACB – k2CCCD. By using a reaction temperature of 34oC and a stirring speed of 400 rpm, the best conditions were obtained using a catalyst of 5.3% by volume, with the reaction rate constant to the right (k1) being 0.014 L/(gmol min), the value of the equilibrium constant (K=k1/k2) is 5.51 and the balance conversion is 77%.

Synthesize and characterization of ZIF-8/NaP zeolite composites as a stable acid-base catalyst for organic reactions

Two ZIF-8/NaP zeolite nanocomposites were synthesized through two different methods by adding ZIF-8 or its precursors on the zeolite mother gel and subsequently characterized. The preparation of a micro-meso structure catalyst with strong acid sites was confirmed. The obtained composites were used for esterification reaction of acetic acid by four different alcohols and aldol condensation of benzaldehyde derivatives 2-X and 4-X to evaluate catalytic activities and compare synthesis methods on the applications. The results show that ZIF-8/NaP composite catalyst brings 94.7% and 91.4% efficiency for esterification and aldol condensation reactions, respectively. This catalyst leads to stabilize the structure of ZIF-8 and increase the stability of ZIF-8 in acidic media.

Facile synthesis of HPW@MOF-199 embedded in SBA-15 functionalized with -COOH groups as a steady catalyst for the esterification reaction

In this work, we successfully synthesized a novel composite (HPW@MOF-199/SBA-15C, PMS-15C) in which MOF-199 encapsulated HPW catalyst (named HPW@MOF-199) was confined in SBA-15C, which is the carboxy-functionalized SBA-15. Physicochemical properties of the composites PMS-15C were systemically characterized by N2 adsorption–desorption isotherms, wide-angle and low-angle XRD, XPS, FT-IR, SEM, and TEM. The results exhibited that HPW@MOF-199 had been successfully synthesized and embedded into the SBA-15C pores by COOH on the surface of SBA-15C. Meanwhile, the composites PMS-15C exhibited high activity and excellent reuse properties in the esterification reaction of acetic acid and ethanol, and no evidence of aggregation, leaching, or inactivation of HPW@MOF-199 during repeated use. The good dispersion of HPW within the MOF-199 cage and the interaction between HPW@MOF-199 and SBA-15C may be responsible for the good catalytic activity as well as the high stability of PMS-15C.

Sulfonated Mesoporous Silica-Carbon Composite Derived from a Silicate-Polyethylene Glycol Gel and Its Application as Solid Acid Catalysts

Solid acid catalyst is a promising alternative to the counterpart homogeneous acid for esterification reaction from the viewpoint of reusability and environmental concerns. This work aims to develop sulfonated mesoporous silica-carbon composite as solid acid catalyst for the esterification. The catalyst was synthesized from sodium silicate as the silica precursor and polyethylene glycol (PEG) as both carbon precursor and template via a sol-gel route in an aqueous system. Then, it was carbonized to produce mesoporous silica-carbon composite. Using the proposed method, the surface area of the silica-carbon composite could reach as high as 1074.21 m2/g. Although the surface area decreased to 614.02 m²/g when it was functionalized with sulfonate groups, the composite had a high ionic capacity of 5.3 mEq/g and exhibited high catalytic activity for esterification reaction of acetic acid with ethanol. At a reaction temperature of 80 °C, the acetic acid conversion reached 76.55% in 4 h. In addition, the catalyst had good reusability, which can be comparable with the commercial catalyst Foltrol F-007. It appears that the sulfonated silica-carbon composite prepared from sodium silicate using PEG as the carbon source a promising candidate as catalyst for esterification and the related area. 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).

Novel SPVA/g-C3N4-SA/PAN Pervaporation Membranes with Porous Catalytic Layers for Esterification Enhancement

The pervaporation membrane technology integrated with catalytic function improves the conversion of esterification reactions by integrating reaction and separation processes in a single step. Optimizing the structure of the catalytic layer of the pervaporation membrane can effectively reinforce its enhancement effect on the esterification reaction. Here, a porous catalytic layer with high catalytic activity and low mass transfer resistance was successfully developed by the immersion phase inversion. The sulfonated poly(vinyl alcohol) (SPVA) catalytic layer prepared by cross-linking poly(vinyl alcohol) (PVA) with 5-sulfosalicylic acid (SSA) was coated on a graphitic carbon nitride-sodium alginate (g-C₃N₄-SA) membrane with polyacrylonitrile (PAN) as the support. The prepared pervaporation membranes with a porous catalytic layer were characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray photoelectron spectroscopy (XPS). The membrane catalytic performance was evaluated in the esterification reaction of acetic acid with ethanol in a pervaporation catalytic membrane reactor (PVCMR). As a result, the acetic acid conversion was up to 98.4% in 12 h at 75 °C with 20% molar fraction of the catalyst. Compared with the batch reaction (BR) under the same operating conditions, the acetic acid conversion rate was greatly improved by 24.4%. After five runs, the membrane still maintained excellent stability. In addition, the resistance-in-series model was considered to analyze the mass transfer resistance of the membrane. The results indicated that the porous catalytic layer had a lower mass transfer resistance of 1.38 × 10⁵ s·m–¹, accounting for only 46.1% of the overall resistance, while the dense catalytic layer accounted for 66.9%. Therefore, the pervaporation membrane with a porous catalytic layer presented great ability for enhancing the esterification reaction of acetic acid with ethanol.

Preparation of n-amyl acetate via esterification of acetic acid and n-amyl alcohol using [HSO3-pmim][HSO4]/SiO2 as catalyst: Catalyst preparation, characterization and reaction kinetics

In order to present a green method to produce n-amyl acetate, a novel supported ionic liquids (ILs) catalyst [HSO3-pmim][HSO4]/SiO2 was synthesized by sol–gel method and was used to catalyze the esterification reaction of acetic acid and n-amyl alcohol. The kinetic equations for the esterification were established based on ideal quasi homogeneous (IQH) model and Langmuir-Hinshelwood-Hougen-Watson (LHHW) model. The parameters in the equations were obtained from kinetic experimental data fit using fourth order to fifth order Runge-Kutta algorithm. The morphology, surface elements, structural stability, pore diameter, specific surface area, thermal stability and distribution of acid strength of the fabricated catalysts were characterized in detail, while immobilization yield, corrosiveness and stability of the catalyst were also evaluated. The reaction kinetic performances of [HSO3-pmim][HSO4]/SiO2 were compared with conventional catalysts like sulfuric acid, P-toluenesulfonic acid, [HSO3-pmim][HSO4] and [HSO3-pmim][HSO4]/Silica gel by the reaction kinetic experiments. The equilibrium conversion of acetic acid in the presence of [HSO3-pmim][HSO4]/SiO2 was increased by 10.8% after immobilization. The mean absolute squared error of the kinetic equations of the esterification based on LHHW model and IQH model were 3.87 × 10-5 and 1.49 × 10-4 respectively. LHHW model based on the solid–liquid reaction mechanism were in better agreement with the experimental results. This concept of recyclable supported IL catalyst provides promising applications prospects for the industrial production of n-amyl acetate.

Synthesis of methyl acetate by nano-photocatalyst based on titania: Temperature dependence studies

Design of low energy processes for synthesis of industrially important esters is imperative expanse of research. Sulphonated Titania based nano-catalysts have been prepared by wet impregnation route has been utilizated for low energy photo-catalytic synthesis of methyl acetate at ambient temperature conditions and optimized the parameters for maximum conversion. In the present paper we have carried out the kinetic study of the reaction at optimized conditions of catalyst loading and molar ratio varying the thermal conditions to observe the effect of temperature on the reaction conversion and equilibrium time. Morphology of the catalysts was analysed using Scanning electron microscopy which suggest a stable and oval particle morphology of the catalyst particles. Sulphonation characteristics of the catalyst was characterized by FT-IR analysis in bare as well as activated state. The kinetic data has been modelled according to second order kinetic model to calculate forward rate constant at various temperatures and maximum reaction rate of 6.77 E-05 L 2 g − 1 mol -1 min −1 was observed at 333.15 K. Further activation energy of the reaction has been calculated by Arrhenius equation and Activation energy for the overall process was 22.26 kJ/mol. The reaction enthalpy calculated from Vant Hoff equation was found to be 47.66 kJ/mol and entropy was found to be 142.03 J/mol/K. Therefore this photocatlytic material can efficiently catalyze the esterification reaction of acetic acid and methanol at low energy conditions. This finding has broaden and deepen fundamental understanding of CH 3 C O O H on TiO 2 surface and demonstrate a low energy route for esterification reactions.

Graphitization of Coconut Shell Charcoal for Sulfonated Mesoporous Carbon Catalyst Preparation and Its Catalytic Behavior in Esterification Reaction

Here, we reported the utilization of coconut shell charcoal used for solid acid catalysts and its performance in the esterification reaction of acetic acid and methanol. The graphitization of coconut shell charcoal was carried out by the calcination and KOH activation at the temperature of 400 °C for an hour and continued at the temperature of 800 °C for an hour under nitrogen flow resulted in graphitic carbon. The effect of the addition of KOH activation was observed by varied the weight ratio of coconut shell charcoal as raw material (RM) and KOH. The selected weight ratio of RM:KOH was 1:1, 1:2, and 1:4. The resulted graphitic carbon was sulfonated by heating with the sulfuric acid to obtain a solid acid catalyst. The sulfonic time was evaluated for 5 and 10 hours. The generated particles were characterized to examine the morphology, the crystallinity, the specific surface area, the chemical bonding, and the ionic capacity using Scanning Electron Microscopy (SEM), X-Ray diffraction (XRD), nitrogen gas absorption-desorption, Fourier Transform Infrared Spectroscopy (FTIR), and titration method, respectively. The best condition for graphitization of raw material is the use of RM:KOH = 1:4, resulting in the highest surface area reaching 1259.67 m2/g and the most dominant of the sulfonic group of −SO3 bond. Furthermore, increasing the sulfonating time from 5 to 10 hours led to the increase of the yield of esterification reaction from 85% to 96.57% for graphite synthesized using RM:KOH = 1:4. Copyright © 2020 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).

Esterification of acetic acid in the presence of sulfated clinoptilolite: a model study of upgrading of pyrolysis bio-oil

ABSTRACT In this study, the esterification reaction of acetic acid with n-propyl alcohol was studied on a sulfated zeolite catalyst to improve the bio-oil obtained by pyrolysis of lignocellulosic biomass. Temperature (323–353 K), sulfuric acid concentration (1–3 M) and time (1–4 hours) were selected as parameters in the preparation of sulfuric acid-modified clinoptilolite samples. Sulfated zeolites samples are characterized by XRF, XRD, and N2 adsorption/desorption techniques. It was observed that the zeolites treated with sulfuric acid retained their crystal structures, decreased surface areas, and changed SiO2/Al2O3 ratios. Samples modified with sulfuric acid are more effective in the esterification reaction than unmodified zeolite. The increase in sulfuric acid concentration and temperature in the modification process increased the conversion of acetic acid in the esterification reaction. The highest acetic acid conversion (63.8%) was obtained with zeolite treated at 323 K temperature, 3 M sulfuric acid for 1 hour.

Enhanced Catalytic Activity of Nano-Fe2O3–MCM-48–SO4 as a Green Catalyst for the Esterification of Acetic Acid with Methanol

Coupling of sulphated iron oxide with MCM-48 was carried out to prepare an efficient heterogeneous catalyst for the esterification reaction of acetic acid with methanol to produce methyl acetate as desired product. The prepared catalyst has shown a remarkable acid conversion of about 90% under optimized reaction conditions, which has resulted in an approximate 71% enhancement in catalyst activity using Fe2O3–MCM-48–SO4 catalyst over bare MCM-48. The effect of various reaction parameters like calcination temperature and time, amount of metal oxide and active species, catalyst loading and reaction temperature were also studied to optimize the catalytic activity of Fe2O3–MCM-48–SO4. The prepared catalyst was characterized using SEM–EDS, FT-IR, XRD and BET techniques. In addition, a detailed kinetics of esterification reaction has been carried out and a possible reaction pathway is also proposed.

Catalytic hydrogenolysis of glycerol into propyl acetate with ruthenium complexes

Ru complexes have been utilized as catalyst precursors for glycerol hydrogenolysis under mild conditions, which gave propyl acetate (PA) as a major product. Notably, the esterification reaction of acetic acid with glycerol can prevent glycerol from polymerization. In(OTf)3 played a critical role in facilitating esterification of glycerol and sequential dehydration, while the Ru complexes' function was hydrogenation. The promoter (FeCl3) can suppress the reduction of Ru complex to Ru particles, improving the catalytic performance. The present catalytic system can give full glycerol conversion and 57% yield of PA. Finally, the reaction pathway was proposed accordingly.

COMPARISON OF SOLVOTHERMAL AND IONOTHERMAL METHODS ON CATALYTIC ACTIVITY OF MIL-53 (Fe)

Iron based MIL-53 (Fe) was synthesized by solvothermal and ionothermal methods. Then the synthesized materials were sulfated to increase the acidic property. Characterization of synthesized and sulfated materials were performed by FT-IR, BET, XRD and TGA methods. The sulfated materials were used in esterification reaction of acetic acid to test the catalytic activity. The effect of synthesis method on the structure of MIL-53 (Fe) and also effects of temperature, time and sulfation of samples on the conversion of acetic acid were studied. Also reusability of sulfated samples was achieved by washing with pure water. In ionothermal synthesis of iron based metal organic framework, deep eutectic solvent formed by choline chloride and dimethyl urea was used as solvent.

Synthesis of n-Amyl Acetate in a Pilot Plant Catalytic Distillation Column with Seepage Catalytic Packing Internal

The n-amyl acetate synthesis from the esterification reaction of acetic acid and n-amyl alcohol in a pilot plant catalytic distillation column with a decanter was evaluated. A novel catalytic packing, seepage catalytic packing internal (SCPI), is applied in this study. Catalytic distillation experiments using different feed molar ratios and feed modes at different column pressures were performed to validate an equilibrium stage model developed to investigate the influence of operation parameters on the performance of the catalytic distillation process. The results from experimental runs and simulations clearly indicate that it is important to the performance of catalytic distillation process to adjust the composition and temperature profiles along the reaction zone. The studies also showed that the integration of a reactive distillation column with a decanter is considered a potential candidate to produce amyl acetate. With proper operation parameters (operating pressure of 20–22 kPa and mixed feeding mod...

Esterification of levulinic acid with ethanol catalyzed by sulfonated carbon catalysts: Promotional effects of additional functional groups

Analysis of literature data on acid-catalyzed esterification reaction of levulinic acid (LA) with ethanol (EtOH) has suggested that some sulfonated carbon catalysts exhibit higher active-site performance than other solid acid catalysts such as macroreticular resins bearing sulfonic acid groups, zeolites, mesoporous silica functionalized with alkyl- and arene-sulfonic acid groups. To elucidate factors that enable the higher performance of sulfonated carbon catalysts, a series of sulfonated carbon catalysts was synthesized by sulfonating various carbon materials whose concentrations of surface oxygen-containing functional groups, porous structure, and swelling ability differ significantly. The catalysts were tested not only in the liquid-phase esterification reaction of LA with EtOH but also in the reaction of acetic acid (AcA) with EtOH because the latter reaction serves as a test reaction to probe the performance of –SO3H sites with minimal influence by mass transfer limitation and to provide an insight into a role of γ-keto group of LA in catalysis. The results show that all catalysts exhibit nearly the same turnover frequency per –SO3H site in the esterification reaction of AcA with EtOH despite widely different structural properties. In contrast, the data indicate that neighboring functional groups such as –COOH and –OH facilitate the reaction of LA with EtOH presumably through hydrogen-bonding interaction between these surface functional groups and γ-keto group of LA. These results suggest a general design strategy to improve the performance of solid acid catalysts further by precisely tuning the distance between –SO3H sites and neighboring functional groups.