Simultaneous Esterification Research Articles

All-natural, hydrophobic, biodegradable cellulose-based straws through simultaneous esterification and filling with stearic acid for cold beverages.

Disposable plastic straws have caused severe environmental pollution because microplastics produced in the degradation process harm human health and marine ecosystems. Paper straws as substitutes need to be incorporated into hydrophobic agents and other chemicals to achieve hydrophobicity, which may be harmful to human health. In this study, a novel and purely natural hydrophobic cellulose-based straw was made from bleached bamboo fibers (BBF) and stearic acid (SA). The prepared straw (BBF/SA@straw) exhibited improved hydrophobicity, biodegradability, and applicability. The water absorption rate was maintained at 58.66 % using single-factor analysis and response surface methodology and the maximum water contact angle was up to 133o. Additionally, the paper straw was almost completely degraded after 50 days in soil. Moreover, it could be used normally in water at 0 °C and 25 °C and was suitable for various beverages (tea, coffee, coke, and milk), demonstrating an extensive application prospect. This work supplies a promising and green alternative to plastic straws, alleviating the burden of white pollution in the environment.

Synthesis of the acidic/magnetic catalyst x-MoO3/Ni0.5Zn0.5Fe2O4 by combustion reaction and evaluation of its catalytic potential/reuse in biodiesel production

The objective of this work was to synthesize a new catalyst x-MoO3/Ni0.5Zn0.5Fe2O4 using the combustion reaction method and to evaluate its catalytic potential and reuse in biodiesel production from waste oil, optimizing the process through experimental design. The catalysts were characterized in terms of structure by X-ray diffraction and phase quantification by Rietveld refinement, surface area by the Brunauer-Emmett-Teller technique, experimental density by helium pycnometry, acidity tests by ammonia desorption at programmed temperature, chemical analysis by X-ray fluorescence, morphology by scanning and transmission electron microscopy, and catalytic properties. The products of the simultaneous transesterification and esterification reactions were characterized by gas chromatography and acidity index. The results indicate the formation of catalysts with surface area ranging from 1.5 to 1.7 m2/g and density ranging from 4.5 to 5.1 g/cm3, composed of major crystalline phases of MoO3 in the orthorhombic configuration and cubic Ni0.5Zn0.5Fe2O4 ferrite, with total acidity ranging from 70 to 182 μmol/g of NH3. Morphological characterization revealed that the catalyst comprises irregular plates of various sizes and shapes with a wide range of cluster sizes. In the simultaneous transesterification and esterification reactions of residual oil, the catalysts were active under all conditions tested, with emphasis on the catalyst containing 50 % Mo ions and 50 % Ni0.5Zn0.5Fe2O4 presenting the best catalytic performance with a conversion of 95 % in ethyl esters and a reduction of 71 % in acidity, with a service life of 6 cycles, an average conversion of 90 % and good thermal and structural stability after use. The experimental design was significant and predictive, with a confidence level of 95 %. Statistical analysis identified that all input variables (temperature, time, and amount of catalyst) were significant for the adopted design. The new catalyst composed of molybdenum, iron, nickel, and zinc has a positive impact on biodiesel synthesis from frying oil and ethanol.

Synergistic effect of La2O3-Al2O3 based catalysts for efficient biodiesel production

Comprehensive synergistic effect of La2O3-Al2O3 on the catalytic performance of transesterification reaction of palm oil with methanol for biodiesel production was studied. The prepared catalyst possessed bifunctional acid-base properties. The well-balanced of acido-basic sites amounts over the catalyst at the La2O3 loading of 40 % and the calcined temperature of 600 °C gave the maximum fatty acid methyl ester (FAME) content of 93.12 %, under the optimum conditions of 1:30 molar ratio of oil to methanol, 200 °C reaction temperature, 39 bar reaction pressure, 5 wt% catalyst loading and 5 h reaction time. The catalyst exhibited reasonable stability. The partial leaching of La3+ ions and deposition of organics resulted in the loss of activity. The results showed that the catalyst generated new weak basic sites and more effective in the transesterification compared to strong basic sites as reported previously. The different strengths of new acid sites were also formed. The balancing of acid-base sites amount was a key to control the catalytic activity and the formation of side reactions. This gives critical guidance in further catalyst development for biodiesel production of waste oils or low-quality oils via simultaneous esterification and transesterification, which helps the biodiesel system being economical and scalable.

Biodiesel production via simultaneous esterification and transesterification of Periplaneta americana oil with liquid lipase Eversa® transform 2.0

Undeveloped Periplaneta americana oil (acid value 38.32 mg KOH/g) was directly used for one-step production of biodiesel with lipase without acid-pretreatment step for the commercial alkaline process. Biodiesel was produced via simultaneous esterification and transesterification of Periplaneta americana oil in the presence of lipase Eversa® Transform 2.0 (ET2) (12 US$/kg) in solvent-free system. The maximum biodiesel yield of 98.63 % was obtained under the optimized conditions of 32 °C, 8.5 wt.% lipase dosage, 8 h, 6.5/1 methanol/oil molar ratio, and 4 wt.% water. Lipase ET2 was recycled 6 times at > 89.52 % biodiesel yield. Biodiesel yield of 93.94 % was further achieved in a 1 L reactor with 15.08 g/kg lipase/biodiesel. Biodiesel cost was estimated as 589.3 US$/ton. Kinetics study gave activation energy of 24.50 kJ/mol with kinetic Michaelis constant of 1.19 mol/L. The physicochemical properties of biodiesel met both Chinese national and US ASTM standards that could be blended with petro-diesel to be applied in both countries. This study suggests that lipase could directly catalyze waste oils for the production of biodiesel at low temperature.

Optimization of biodiesel production from coconut oil using a bifunctional catalyst derived from crab shell and coconut shell

The utilization of renewable biomass resources for biofuel production has gained widespread popularity as an effective means of converting waste into a valuable resource. This study investigated the optimization of biodiesel production from coconut oil (CO) using a bifunctional catalyst derived from crab shell and coconut shell. The catalyst underwent characterization through Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, and Brunauer-Emmett-Teller. The acid precursor for the bio-based bifunctional catalyst was created from carbonized and sulfurized coconut shell, while the base precursor was obtained from calcined and KOH-treated crab shell. The experimental design was optimized using Box-Behnken design for the simultaneous esterification and transesterification of CO. Response surface methodology was employed to model and optimize the process. Under the determined ideal conditions, which included a methanol to oil ratio of 16.75:1, a 1.00% catalyst loading, a temperature of 58.19 °C, and a reaction time of 78.76 minutes, a CO methyl ester yield of 85.73% was achieved under experimental conditions. This yield closely aligned with the predicted range of 85.84% as per the model. The resulting methyl ester (biodiesel) obtained under these optimized conditions exhibited physicochemical properties well within the requirements specified by ASTM D6751 set by the International Organization of Standardization.

Microalgal synthesis of the biodiesel employing simultaneous extraction and esterification via heterogeneous catalyst

Within the realm of biorefinery, the third generation of biodiesel production relies on extracting oil from Algae to create renewable fuels. Algae cultivation can occur under precise laboratory conditions, making them a sustainable substitute for Fatty Acid Methyl Ester or biodiesel production. Through analysis of the simultaneous extraction and (trans)esterification process of Algae Chlorella Minutissima utilizing sulfated carbonaceous catalysts, scientists have discovered an efficient technique for producing biodiesel. Various parameters, such as catalyst loading, oil-to-methanol ratio, reaction temperature, and reaction time for FFA reduction and FAME yields, were studied and optimized. Results indicate that utilizing a 10 wt% catalyst loading and a 70:30 volumetric oil to methanol ratio can achieve 67.59 % FFA reduction and a biodiesel yield of 44 mL. This method of producing biodiesel can occur in a single-unit operation, leading to higher yields of renewable fuel at a reduced cost and energy consumption. Finally, the quality of the biodiesel produced met ASTM D6751 standards, confirming its suitability for use.

Optimization of Methyl Ester Through Simultaneous Esterification –Transesterification Reactions Using Waste Cooking Oil as Raw Material

The increasing need for fossil energy does not equal the availability of alternative energy sources as a substitute generating new problems. In addition to decreasing availability, fossil energy harms the environment by producing dangerous gases from combustion such as carbon dioxide, sulfur, and nitrogen. These factors increasingly encourage researchers to create renewable energy sources with the same performance but are environmentally friendly. Biodiesel or Methyl Ester commonly called Fatty Acid Methyl Ester (FAME) is a renewable alternative energy produced from various raw materials such as animal, vegetable, or other oils. In this study, the methyl ester made from waste cooking oil was processed through two stages of esterification and transesterification using the addition of methanol with different catalysts, H2SO4 and NaOH relying on the reaction step. The research aimed to determine the optimal results from variations in the concentration of the acid catalyst used. From FTIR characterization found that functional groups indicating the formation of methyl esters have been identified at wave numbers 1800-1700 cm-1 with functional groups of -C=O ester the presence of FAME. Meanwhile, to determine the optimum methyl ester caloric value using Bomb Calorimetry according to ASTM D6751 standard. The caloric value was obtained at 9,572.58 Cal/g with catalyst 0,5% H2SO4. The methyl ester content was identified using GC-MS, and the results obtained for ME1, ME2, and ME3 are 74.90%, 77.15%, and 71.98%, respectively. From this study, it can be found that the methyl ester can be produced with esterification-transesterification reactions simultaneously.

Preparation of Brönsted-Lewis dual acidic catalyst Ce-HPW-F and its simultaneous catalytic esterification and transesterification of oleic acid and castor oil with methanol to synthesize biodiesel

A series of Brönsted-Lewis dual acidic catalyst Ce(x)-HPW-F(x = 1/3, 2/3, 1, 4/3, x is the molar ratio of Ce to HPW) were synthesized by introducing Ce3+ and F- into 12-tungstophosphoric acid (H3PW12O40, HPW) with Keggin structure. The structure, morphology, valence state, elemental composition, acid site density and type of Ce-HPW-F catalyst were analyzed by FT-IR, XRD, BET, SEM, XPS, NH3-TPD, and Py-IR. The catalytic activities and stabilities of the obtained catalysts were studied in the esterification and transesterification reactions of oleic acid and castor oil (Simulated acidified oil, SAO). The Ce(1/3)-HPW-F has presented optimum catalytic activity. A yield of fatty acid methyl esters (FAME) 93.0 % was obtained at the 18:1 methanol to SAO molar ratio, 4 wt% catalyst, 110°C reaction temperature and reaction time of 90 min. The high catalytic activity of Ce(1/3)-HPW-F could be attributed to the strong Brönsted and Lewis acidity. The Lewis acidity was generated from the partial exchange of Ce3+ with the proton (H+) in HPW and increased through the formation of Ce-F bond between the strongly electronegative F- and Ce3+. Meanwhile, in the highly polar medium (methanol), the binding force between O and H+ was reduced due to the negative charge dispersion of the outer oxygen in the phosphotungstic acid anion and the polarization of W=Od formed by the terminal O and W. This may lead to the stepwise dissociation of H+ in HPW that had not been exchanged by Ce3+. However, F- could form the hydrogen bond with H+ to avoid the occurrence of the above phenomenon. After reusing Ce(1/3)-HPW-F catalyst for four times, the total yield of FAME could still achieve more than 75 %.

Biochar-based bi-functional catalyst derived from rubber seed shell and eggshell for biodiesel production from waste cooking oil

The application of biomass-based sources for energy generation has attracted much interest in recent times due to theirenvironmental benefits. In this study, the potential use of rubber seed shells and eggshells in the synthesis of bi-functional catalysts for biodiesel production has been investigated. The catalyst was produced in a sequence of steps that includedcarbonization, sulfonation, calcination, and impregnation. The catalyst was characterized using Scanning electron microscopy, X-ray fluorescence spectrophotometry, Fourier transform infrared spectroscopy, X-ray diffraction, and Brunauer-Emmett-Teller analysis. The catalysts’ performance was assessed throughthe simultaneous esterification and transesterification of waste cooking oil with a free fatty acid content of 2.9 %. Response surface methodology based on central composite design was employed to model and optimize the process. The factors investigated included methanol/oil ratio (4:1 – 20:1), catalyst concentration (1 – 5 wt%), reaction temperature (50 – 70 °C), and time (1 – 5 h). The catalyst was found to have a specific surface area of 241.0 m2/g, a pore volume of 0.189 cc/g, and a pore size of 1.132 nm. A methanol/oil molar ratio of 14.2:1, catalyst concentration of 2.0 wt%, temperature of 62.5 °C, and reaction time of 2.3 h were the optimum reaction conditions required to achieve an optimum average biodiesel yield of 89.4 % and FFA conversion of 91.8 %. Also, the leaching of the catalysts wasinsignificant, and the catalysts demonstrated good reusability, producing a biodiesel yield of 81.9 % after the fifth cycle. The physicochemical properties of the produced biodiesel fall within the ranges of the recommended ASTM 6751 and EN14214 international standards. The utilization of rubber seeds and eggshells for catalyst synthesis offers a promising, cost-effective, and eco-friendly way to produce biodiesel.

Using ZnAl–LDH@SiO2 as a catalyst for the electrocatalytic conversion of waste frying oil into biodiesel

In this study, a novel electrocatalytic conversion system via simultaneous esterification and transesterification, based on a ZnAl–layered double hydroxide (LDH)@SiO2, was investigated for fatty acid methyl ester (FAME) production from waste frying oil (WFO). A mechanism is proposed for the (trans)esterification process to generate CH3O− and OH− on the ZnAl–LDH@SiO2 as the semiconductor heterogeneous catalyst. The inclusion of SiO2 enhanced the catalyst's basicity and caused a better exposure of atoms of oxygen atoms on the catalyst's surface which contributed to the formation of methoxides as a nucleophilic attack on the triglyceride's carbonyl. Also, ZnAl–LDH@SiO2 as an electrocatalyst reduces the beginning potential rate and increases the charge carriers transport. The results showed that 98.4% FAME yield was obtained at higher water content from WFO after 90 min of reaction at 25 °C using 2 wt% of the ZnAl–LDH@SiO2 catalyst, and a methanol to WFO (M:WFO) molar ratio of 6:1. ZnAl–LDH@SiO2 was also effective for WFO containing 3.3 wt% of free fatty acid (FFA), and indicated high stability for WFO (trans)esterification after 5 runs. The electrocatalytic conversion system has the potential to advance a new process development for the conversion of feedstock containing high FFA and water to produce the second generation of biodiesel.

Synthesis of a novel acid-base bifunctional Zn/Ca–Zr catalyst for biodiesel application: Experimental and molecular simulation studies

A novel acid-base bifunctional Zn/Ca–Zr catalyst has been synthesized successfully for biodiesel production from palm oil and acidified oil. The influence of synthetic factors on the catalytic activity of resulting Zn/Ca–Zr were discussed. Furthermore, the FAMEs yield was optimized to achieve the maximum value using the Taguchi approach. Results showed that the catalyst synthesized using a metal stoichiometric ratio of 4 : 4: 4, hydrothermal conditions, and activation temperature of 850 °C exhibited the best activity. The highest FAMEs yield was found to be 94.9% under the conditions of 5 wt% catalyst dosage, methanol/palm oil molar ratio of 20, and temperature of 170 °C at 3 h. The contribution percentage indicated that the methanol/oil molar ratio had the most significant effect on the FAMEs yield. Moreover, the Zn/Ca–Zr catalyst can catalyze the simultaneous esterification and transesterification of acidified palm oil with a 95.1% FAMEs yield and 93.3% acid reduction rate. And a 78.2% FAMEs yield can be maintained after four repeated cycles. Molecular simulations indicated the active site of Zn was more easily attacked by FFAs for esterification, while the active site of Ca was retained to adsorb methanol for transesterification, which explained the catalyst's acid-base bifunctional characteristics.

Synthesis and application of biomass-derived magnetic biochar catalyst for simultaneous esterification and trans-esterification of waste cooking oil into biodiesel: modeling and optimization

This work created, characterized, and used a magnetic biochar catalyst that is both eco-friendly and very effective. Sugarcane bagasse was selected as primary raw material for catalyst preparation, because it is renewable and ecofriendly biomass. Catalyst created by doping sugarcane bagasse biochar with magnetic material in the form of (FeSO4·7H2O). Thermogravimetric Analysis (TGA) and Fourier Transform Infrared spectroscopy (FTIR) were used to characterize the catalyst. In addition, physical and textural characteristics of the catalyst were identified and interpreted. The characterization outcome showed that the catalyst has good catalytic qualities. For the manufacturing of biodiesel, discarded cooking oil served as the primary feedstock. The experiment was created utilizing the Box–Behnken Design (BBD) technique. There are four variables with the following three levels each: temperature, methanol to oil ratio, catalyst concentration, and reaction time. 29 experiments in total were carried out. Using the RSM function, optimization was done. The optimal conditions for obtaining biodiesel yield—temperature, methanol to oil ratio, reaction time, and catalyst weight—were 43.597 °C, 9.975 mol/L, 49.945 min, and 1.758 wt%. A study of the produced biodiesel using a FTIR showed that the conventional biodiesel IR spectra were confirmed. All physiochemical characteristics found suggested the biodiesel complied with ASTM and EN norms. Overall, the synthesized catalyst had conducted simultaneous reactions in a single batch reactor and had demonstrated suitability for converting used cooking oil to biodiesel.

Biodiesel Production from Waste Cooking Oil via β-Zeolite-Supported Sulfated Metal Oxide Catalyst Systems.

Waste cooking oil (WCO) is a readily available and cheap feedstock for biodiesel production. However, WCO contains high levels of free fatty acids (FFAs), which negatively impact the biodiesel yield if homogeneous catalysts are used. Heterogeneous solid acid catalysts are preferred for low-cost feedstocks because the catalysts are highly insensitive to high levels of FFA in the feedstock. Therefore, in the present study, we synthesized and evaluated different solid catalysts, pure β-zeolite, ZnO-β-zeolite, and SO42-/ZnO-β-zeolite for the production of biodiesel using WCO as feedstock. The synthesized catalysts were characterized by Fourier transform infrared spectroscopy (FTIR), pyridine-FTIR, N2 adsorption-desorption, X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy, while the biodiesel product was analyzed using nuclear magnetic resonance (1H and 13C NMR) and gas chromatography-mass spectroscopy. The results revealed that the SO42-/ZnO-β-zeolite catalyst showed excellent catalytic performance for simultaneous transesterification and esterification of WCO, with a higher percentage conversion than the ZnO-β-zeolite and pure β-zeolite catalyst, due to the large pore size and high acidity. The SO42-/ZnO-β-zeolite catalyst exhibits 6.5 nm pore size, a total pore volume of 0.17 cm3/g, and high surface area of 250.26 m2/g. Experimental parameters such as catalyst loading, methanol:oil molar ratio, temperature, and reaction time were varied in order to establish the optimal parameters. The highest WCO conversion of 96.9% was obtained using the SO42-/ZnO-β-zeolite catalyst under an optimum reaction condition of 3.0 wt % catalyst loading, 200 °C reaction temperature, and 15:1 molar ratio of methanol to oil in 8 h reaction time. The WCO-derived biodiesel properties conform to the ASTM6751 standard specification. Our investigation of its kinetics revealed that the reaction follows a pseudo first-order kinetic model, with an activation energy (Ea) of 38.58 kJ/mol. Moreover, the stability and reusability of the catalysts were evaluated, and it was found that the SO42-/ZnO-β-zeolite catalyst exhibited good stability, giving a biodiesel conversion of over 80% after three synthesis cycles.

Removal of Aqueous Pb2+ on Partially esterified Cellulose Obtained by Almond Shell Dissolution Using Deep Eutectic Solvent

Microcrystalline cellulose (MCC) was isolated from the almond shell after its pretreatment with an acidic deep eutectic solvent (DES) of choline chloride/oxalic acid under microwave irradiation. The Fourier transform infrared spectroscopy analysis showed that the spectrum of the isolated (MCC) includes an additional peak at 1747.0 cm−1 which refers to the (C=O) esters and carboxylic peak. This indicates that the MCC surface has undergone simultaneous partial esterification during the isolation process. Owing to its favorable structural and morphological properties, the isolated MCC was successfully employed for the adsorption of aqueous Pb2+ ions with (50 mg/g) efficiency using a 3.0 g/L adsorbent dose at pH (6.5) and 20 °C. The adsorption was spontaneous near the ambient temperature, pH dependent, and exothermic. The Coulomb forces are the foremost adsorption driving force. The reusing of the spent DES and adsorbent for four successive rounds, affirmed their applicability on industrial scales.

Valorization of hazardous waste cooking oil for the production of eco-friendly biodiesel using a low-cost bifunctional catalyst

Biodiesel is considered the prospective substitute for non-renewable fossil fuel-derived sources of energy. However, the high costs of feedstocks and catalysts inhibit its large-scale industrial implementation. From this perspective, the utilization of waste as the source for both catalyst synthesis and feedstock for biodiesel is a rare attempt. Waste rice husk was explored as a precursor to prepare rice husk char (RHC). Sulfonated RHC was employed as a bifunctional catalyst for the simultaneous esterification and transesterification of highly acidic waste cooking oil (WCO) to produce biodiesel. The sulfonation process coupled with ultrasonic irradiation proved to be an efficient technique to induce high acid density in the sulfonated catalyst. The prepared catalyst possessed a sulfonic density and total acid density of 4.18 and 7.58mmol/g, respectively, and a surface area of 144 m2/g. A parametric optimization was conducted for the conversion of WCO into biodiesel using the response surface methodology. An optimal biodiesel yield of 96% was obtained under the conditions of methanol to oil ratio (13:1), reaction time (50min), catalyst loading (3.5 wt%), and ultrasonic amplitude (56%). The prepared catalyst showed higher stability up to five cycles with biodiesel yield greater than 80%.

Biodiesel Production from Waste Oil Catalysed by Metal-Organic Framework (MOF-5): Insights on Activity and Mechanism

The activity of MOF-5-based solids has been exploited in the simultaneous transesterification and esterification of acid vegetable oils. For this purpose, three different types of MOF-5 have been synthesized and characterized, and then tested in the above-mentioned reactions. It has been demonstrated that the “regular MOF-5” was a suitable catalyst for biodiesel synthesis from waste oil also, rich in FFA (Free Fatty Acids). Moreover, to identify the true structure that acts in the reactions and possible structural modifications due to the presence of alcohols, proper studies have been performed. The results have evidenced a distortion of the regular structure of MOF-5 due to the breakage of some zinc bonds between the cluster and organic framework.

Controllable preparation of nano-cellulose via natural deep eutectic solvents prepared with lactate and choline chloride

Pretreatment with deep eutectic solvent is highly desirable to improve the efficiency of the preparation of nano-cellulose and simplify the operation. The natural deep eutectic solvent (NADES) composed of lactate (LA) and choline chloride (CC) was applied for the preparation of nano-cellulose under mild conditions accompanied by simultaneous esterification modifications of it. The effects of the treatment conditions on the structure and properties of nano-cellulose were investigated and explained the mechanism from the perspective of molecular simulation. The results showed that the reaction time of nano-cellulose could be shortened to 3 h, and the reaction temperature could be as low as 100 °C. The esterification of cellulose not only avoided over-hydrolysis and dissolution in the pretreatment process but also ensured the high yield of nano-cellulose (up to 75 %−89 %). The crystallinity of nano-cellulose decreased compared with the raw material due to the influence of mechanical action. The nano-cellulose fibers (NCF) and nano-cellulose crystals (NCC) with different lengths were achieved by controlling the reaction conditions of the pretreatment of NADES. The esterification modifications of NADES on cellulose during the dissolution of nano-cellulose were confirmed by molecular simulation. The nano-cellulose prepared by this system has good stability, biocompatibility, and degradability, which can be used in the fields of medicine, strengthening composite materials, and emulsion emulsifiers.

Synthesis of Sn-CaO as a bifunctional catalyst and its application for biodiesel production from waste cooking oil

Herein, a simple solid-state method was employed to synthesize a bifunctional tin (Sn) supported calcium oxide (CaO) catalyst. The synthesized catalyst (Sn-CaO) was found to be suitable for the conversion of waste cooking oil to biodiesel in a single-step reaction procedure. To achieve maximum conversion, the physicochemical and surface morphological characteristics of the catalyst were investigated using FTIR, XRD and FESEM-EDX. Box-Behnken Design based on Response Surface Methodology was used to optimize biodiesel conversion. At optimized conditions, the variables affecting the reaction were, methanol to oil molar ratio (16.15:1), time (3.42 h), temperature (85.15 °C) and catalyst concentration (2.22% with respect to oil) that led to biodiesel conversion amounting to 97.39%. Three experiments were carried out under these conditions to validate the predicted model. The experimental value of biodiesel conversion in this setting was 96.72 ± 0.61%. The acid value and kinematic viscosity of biodiesel were measured at 40 °C and were determined to be 0.48 mg KOH g−1 and 5.3 mm2 s−1, respectively, fulfilling the ASTM and EN standards. The simultaneous esterification and transesterification reaction mechanism were also described. The finding of this study leads to an economical and environmentally benign approach to biodiesel production.

Parametric and kinetic study of simultaneous esterification and transesterification of model waste sunflower oil by using zirconium sulfate catalyst

Parametric and kinetic study of simultaneous esterification and transesterification of model waste sunflower oil by using zirconium sulfate catalyst

Experimental investigation on biodiesel production through simultaneous esterification and transesterification using mixed rare earth catalysts

In this study, biodiesel production through simultaneous esterification and transesterification of palm oil with 10 wt% of oleic acid using the mixed rare earth catalyst was investigated. The mixed rare earth catalysts were prepared via the co-precipitation method. The effects of the precipitating parameters such as temperature, stirring speed and pH on the physicochemical and morphology of the catalysts were studied. All catalysts were thoroughly characterized using X-ray diffraction (XRD), scanning electron microscopy-energy dispersive spectrometer (SEM-EDS), fourier transform-infrared spectroscopy (FTIR), N2 adsorption/desorption, CO2 temperature programmed desorption (CO2-TPD) and NH3 temperature programmed desorption. (NH3-TPD). The results indicated that the mixed rare earth catalyst prepared under the precipitation conditions: at pH 9, a stirring of 400 rpm and temperature of 30 °C showed the highest catalytic of 90% FAME content. High surface area of the catalyst, a significant larger amount of Ce and La contents in the catalyst and an appropriate amount of acid and basic sites on the catalyst led to the high catalytic activity. The catalyst could also accelerate the initial reaction rate to achieve the high FAME content of 50% within 30 min.