Transesterification Of Ethanol Research Articles

Preparation of biodiesel by transesterification of castor oil catalyzed by flaky halloysite supported ZnO/SnO2 heterojunction photocatalyst

Biodiesel belongs to renewable energy and is a potential substitute for petrochemical diesel. In this study, ZnO/SnO2@halloysite heterojunction photocatalyst was prepared by loading semiconductor zinc oxide and tin dioxide on layered kaolin by the improved wet calcination method, which was used to photocatalytic the transesterification of castor oil and ethanol to produce biodiesel. TG-DTG, BET, XRD, UV–vis and SEM-EDS were used to characterize the composition, specific surface area, light absorption characteristics and photocatalytic performance of the samples. The reaction conditions were optimized by the Taguchi method. The optimum reaction conditions were as follows: catalyst dosage 4 wt%, molar ratio of ethanol to oil 12:1, reaction temperature 75 °C. After 2 h, the yield of biodiesel was 96.75 %. In the study of catalyst reusability, the yield of biodiesel is still above 85 % after being reused for 5 times. The kinetics of photocatalytic transesterification was studied, and the results accorded with quasi-first-order kinetics. The activation energy was 75.02 kJ/mol. Lastly, an eight-step reaction mechanism of photocatalytic transesterification was proposed. The prepared castor oil biodiesel can be prepared into B20 biodiesel through additives or mixing to meet ASTM D6751 and EN 14214 standards.

Selective synthesis of methyl ethyl carbonate intensified by reactive distillation from consecutive transesterification of methyl carbonate and ethanol

Reactive distillation (RD) can be effectively used to improve the selectivity of the intermediate product for complex multi-reaction schemes, which involves using distillation to manipulate the column profiles in the RD column (RDC) to attribute the desired reaction and the manipulating reactions to facilitate separation. As the demand for ethyl methyl carbonate (EMC) has increased significantly due to its structural characteristics, the selective synthesis of EMC from the consecutive transesterification of dimethyl carbonate (DMC) and ethanol (EtOH) in the presence of azeotropes between reactants and products was studied as featured reaction schemes. The basic resin catalyst KC161 is utilized to build the kinetic reaction model and supplement the primary data for the process design. The pilot-scale RD experiments are explored to verify the feasibility and the reliability of the model. The impact of critical operation and structure parameters on the conversion and selectivity of the reaction and the azeotropes formed in the system were analyzed. A hybrid distillation process containing an RDC, pressure-swing distillation columns, and a regular distillation column, was designed and optimized based on minimized total annual cost (TAC) using a sequential iterative algorithm. 0. 9997 (mole purity) EMC and 0. 9999 (mole purity) diethyl carbonate (DEC) were obtained with EMC selectivity up to 0.863%.

Insights into kinetics and reaction mechanism of acid-catalyzed transesterification synthesis of diethyl oxalate

The catalytic performance of different acidic catalysts for diethyl oxalate synthesis from the one-step transesterification of dimethyl oxalate and ethanol was evaluated. The effects of different factors (e.g., acidity, electron accepting capacity, cations type and crystalline water) on the catalytic activity of acidic catalysts were investigated respectively. It was proposed and confirmed that the transesterification reaction catalyzed by a Lewis acid (FeCl3) and a Bronsted acid (H2SO4) follows a first-order kinetic reaction process. In addition, the Lewis acid-catalyzed transesterification processes with different ester structures were used to further explore and understand the speculated reaction mechanism. This work enriches the theoretical understanding of acid-catalyzed transesterification reactions and is of great significance for the development of highly active catalysts for diethyl oxalate synthesis, diminishing the industrial production cost of diethyl oxalate, and developing downstream bulk or high-value-added industrial products.

Sandwich like poly(ionic liquid)s functionalized microspheres: Efficient interfacial catalysts for preparation of biodiesel

Smart photo-responsive nanospheres azo-p(St-TMGILs)-OEt with sandwich like structure were prepared by introducing alkaline ionic liquids (TMG ILs) and a pioneering photo-responsive monomer (azo-TEPIC) on the surface of polystyrene microspheres by one-pot soap-free emulsion polymerization with free radical polymerization. Then the as-prepared nanoparticles were used as interfacial catalysts for constructing Pickering emulsions, wherein, azo-TEPIC was first obtained by using organosilane to functionalize azobenzene. Pickering emulsions can be reversibly switched between emulsification and breakage by alternate exposure to UV and visible light. The Pickering emulsion was used for the transesterification of soybean oil and ethanol to produce biodiesel and was found to give yields above 97% under mild reaction conditions with superior cycling stability of the catalyst.

Synthesis and characterization of polyvalent high-performance synthetic base oil for drilling operations in recalcitrant and unconventional oil and gas reservoirs

Synthetic ester fluid is one of the most widely recommended drilling fluids for unconventional and recalcitrant reservoirs owing to its numerous technical advantages, high sustainability, non-toxic and inherently biodegradable. However, there are serious concerns about its thermal and hydrolytic stability at high temperatures and pressures (HTHP) as well as its viscosity and flow characteristics in low temperature climates such as deep-water wells. Hence, its inability to maintain stable borehole and flat rheology characteristics may invariably threaten its application under these aforementioned scenarios.In this study, a high-performance ternary mixture of synthetic ethyl esters of plants oil (SEEP mixture) fluid was synthesized by a non-catalyzed supercritical ethanol transesterification process using coconut, castor seed and linseed oil as starting materials. The nature, chemistry and fluid particle interactions of the individual components that make up the synthetic ester fluid were critically studied. The process equipment consists of a continuous flow reactor equipped with a PID controlled furnace as heat source to the reactor and a high- pressure transducer. The conversion efficiency was monitored by an Agilent 5500a FTIR machine with attenuated total reflectance (ATR) system while a GC-EIMSD system was used for fatty acid ester compositional analysis. The oil was extracted by a Soxhlet apparatus mechanism. The extracted Plant oil and the synthetic esters were characterized under standard recommended laboratory procedures by API, ASTM and the European Union (EN) standard protocols. Also, fluid's toxicity and biodegradability tests were conducted according to OECD recommended practices. The results were compared with existing synthetic hydrocarbon fluids (SHFs) for HTHP and deep-water wells.The conversion efficiency of the non-catalyzed transesterification process was 96.50%. The amount of oil yield from the plant oil after Soxhlet extraction is commendable. Hence, synthetic ester fluid raw materials are readily available in large quantities and in a sustainable manner. The GC-MS analysis shows that the coconut oil contains 92% saturated fatty acid. Whereas, the castor seed oil contains 98.31% unsaturated fatty acid with 89.75% of mono-unsaturated ricin-oleic acid (D-12-hydroxyoctadec-cis-9-enoic acid). The linseed oil has high content of linolenic acid with 89.60% unsaturated fatty acid. The designed fluid has excellent lubricity characteristics, extremely low cloud and pour point temperatures, higher oxidative stability, low peroxide value, lower copper strip corrosion value and lower kinematic viscosity and density variations with temperatures which signals flat rheology when used to form a synthetic based mud. Also, its flash point and auto-ignition temperatures are high and thus forestall possible fire hazard in high temperature zones. Finally, the fluid is non-toxic and inherently biodegradable.

Supercritical transesterification of vegetable oil and ethanol: temperature and residence time effects on phase formation and water content

Supercritical transesterification has emerged as a readily available alternative for biodiesel production since no catalyst is required, thereby generating fewer waste products. In this research, the supercritical transesterification of refined vegetable oil and aqueous ethanol was carried out at temperatures 400 to 480 °C and a 12:1 ethanol to oil molar ratio, to assess the effect of temperature and residence time in the formation of a homogeneous phase, effluent appearance and increased water content derived from glycerol etherification. The results showed that water was produced at temperatures higher than 400 °C, as expected from the occurrence of glycerol etherification, and that prolonged times resulted in gas and soot formation, indicating esters decomposition. Through water mass balances, it was possible to identify the set of operation conditions in which the water formed from glycerol etherification matched with the maximum expected according to the proposed reaction scheme.

Synthesis of potassium polyferrite KxFeyOz heterogeneous catalyst for sunflower oil ethanolic transesterification

Synthesis of potassium polyferrite KxFeyOz heterogeneous catalyst for sunflower oil ethanolic transesterification

Efficient synthesis of diethyl oxalate from transesterification of dimethyl oxalate and ethanol using alkaline catalysts and kinetic studies of transesterification

A highly efficient catalyst for transesterification of dimethyl oxalate with ethanol was found, and it exhibited a TOF value of 274 032 h−1 at near room temperature.

Production of Biodiesel by Ethanolic Transesterification of Sunflower Oil on Lateritic Clay- based Heterogeneous Catalyst

Production of Biodiesel by Ethanolic Transesterification of Sunflower Oil on Lateritic Clay- based Heterogeneous Catalyst

Optimization and model-based control of sustainable ethyl-methyl carbonate and diethyl carbonate synthesis through reactive distillation

As excellent solvents of lithum-ion electrolyte, ethyl-methyl carbonate (EMC) and diethyl carbonate (DEC) are synthesized through transesterification of dimethly carbonate (DMC) and ethanol. Process intensification, optimization and the corresponding control scheme of the synthesized process are essential when sustainability is becoming a necessity. In the present work, the intensified flowsheet for EMC and DEC production process was firstly proposed and optimized with conventional reactive distillation (RD) and reactive dividing wall column (RDWC), respectively. Compared with RD process, RDWC could achieve 25.3% and 8.2% total annualized cost reduction for EMC and DEC production process, respectively. And carbon dioxide emission could be decreased by 29.4% and 11.7% by further integrating RD and separation column into RDWC arrangement for DEC and EMC production. Then multi-loop PI control schemes were developed as benchmark and linear model predictive controller was designed to handle the persistent feed disturbance. The superiorities of model-based controllers for the strongly interactive and coupled system are demonstrated by the dynamic response comparisons in terms of settling time, overshoot and integral of squared error (ISE), especially for the controlled variables with poor control performance under conventional multi-loop PI control structure. To summarize, the comprehensive control performance index-ISE with MPC is reduced by 55.9%–99.1%, as compared to those under PI control strategy.

Functional production, characterization, and immobilization of a cold-adapted cutinase from Antarctic Rhodococcus sp.

A lipolytic enzyme (Rcut) was discovered from the Rhodococcusstrain (RosL12) isolated from the Antarctic Ross Sea. The corresponding gene composed of 651 bases encoding 216 amino acids. It was found to be a cutinase gene through BLAST search. Rcut has a signal sequence consisting of 29 amino acids. An active Rcut was produced after the intact gene containing the signal sequence was transformed into Escherichia coli Rosetta-gami™ 2 (DE3) pLysS. Rcut was purified through a nickel-nitrilotriacetic acid purification system and a carboxymethyl Sepharose column chromatography. Its specific activity was 2190 U/mg. Rcut showed the highest activity at 40 °C and had a low activation energy of 3.16 kcal/mol. This means that it is a typical cold-adapted enzyme. Rcut showed high activity towards medium chain fatty acids (C4–C10). Rcut degraded polycaprolactone and polyethylene terephthalate, suggesting that it could be used for decomposition of synthetic plastics causing environmental pollution. Rcut was immobilized on methacrylate-divinyl benzene bead. This immobilized Rcut (immRcut) showed higher thermal stability than the free enzyme. ImmRcut performed transesterification of various esters and ethanol in a non-polar solvent, suggesting that it could be used for the synthesis of industrially useful ester compounds.

Simulation and optimization of CSTR reactor of a biodiesel plant by various plant sources using Aspen Plus

AbstractIn the present paper, an integrated continuous process of biodiesel manufacturing is proposed using Aspen Plus simulator for different feedstocks. Majority of the reported simulation models in literature are design models for new processes by fixing some level of equipment performance such as the conversion in reactor. Most models assume the feed oil as pure triglycerides or some fatty acids and the biofuel as pure ester. In order to optimize the production of biodiesel, similarity with reality is necessary. For this purpose, this work uses thermophysical property estimation of glycerides, rigorous reaction kinetics, phase equilibrium for separation and purification units, and prediction of essential biodiesel fuel qualities. Detailed operating conditions, equipment designs, and properties of feed and products were obtained. The reactions and parameters kinetics were applied to represent both methanolic and ethanolic transesterification of the biodiesel production. An evaluation of optimal operating conditions (time, temperature, alcohol: oil ratio) for a CSTR reactor was determined. The optimal conversion was achieved at a temperature of 60 °C, 6.00 mol/mol alcohol-oil ratio and 2.0 h residence time when used methanol transesterification reaction as 88.19, 93.77, 89.43, and 89.25%, respectively for sunflower, soybean, palm and macauba oil, on the other hand 86.09, 80.26, 76.54, and 76.39% for transesterification ethanolic. Most of the biodiesel obtained from the simulations presented adequate according to the specifications of the D6751, ANP 45, and EN 14214 standards. Finally, the model proposed can be used for improving operations conditions, new products design and help economic analysis in continuous processes of biodiesel production.

Predictive Modelling and Surface Analysis for Optimization of Production of Biofuel as A Renewable Energy Resource: Proposition of Artificial Neural Network Search

The present study undertakes the research problem on the optimization of production of biodiesel as a renewable energy resource from the transesterification of soybean oil and ethanol. Predictive modelling and surface analysis techniques were applied based on the artificial neural network search algorithm to correlate the yield of ethyl ester and glycerol and the input parameters. The formulated models accurately predicted the yield of the products with a high coefficient of determination. When the reaction time is low, the ester yield decreases with an increase in temperature and the maximum yield of obtained biodiesel at a very low value of time of reaction and temperature. Plots based on parametric and sensitivity analysis reveals that the yield of ethyl ester can be maximized and that of glycerol minimized at an integrated condition with lower ethanol/oil molar ratio, higher temperature value, higher catalyst concentration value, and longer time of reaction. The global sensitivity analysis reveals that the catalyst concentration and temperature of the reaction influence the yield of ethyl ester the most. In addition, an optimal ethyl ester yield of 95% can be achieved at specific input conditions. Moreover, according to the results of global sensitivity analysis, the catalyst concentration is found to be most significant for both the glycerol and ethyl ester yield.

Mg–Al Mixed Oxide Derived from Hydrotalcites Prepared Using the Solvent-Free Method: A Stable Acid–Base Bifunctional Catalyst for Continuous-Flow Transesterification of Dimethyl Carbonate and Ethanol

Mg–Al oxides were prepared by facile solvent-free grinding of Mg–Al layered double hydroxide and were used as catalysts for continuous-flow transesterification of dimethyl carbonate and ethanol. Th...

Biodiesel production from Halamphora coffeaeformis microalga oil by supercritical ethanol transesterification

The marine benthic diatom Halamphora coffeaeformis is a potential feedstock for biodiesel production. This species shows high growth rates, important triacylglycerol (TAG) contents and grows in seawater making large-scale cultivation advantageous. Moreover, sustainable biofuel production in future biorefineries requires the implementation of technologies that employ renewable solvents. Thus, the goal of this work was to evaluate ethanol usage as extraction solvent and reaction medium for biodiesel production from H. coffeaeformis. In a first step a bio-oil extraction was carried out comparing ethanol and n-hexane to investigate the performance of ethanol with respect to a conventional solvent. Then, a free-catalyst supercritical ethanol transesterification of the bio-oils was carried out to obtain biodiesel. Higher lipid extraction yields were obtained using ethanol respect to n-hexane (26 wt.% vs 21.1 wt.%). The transesterification of crude lipids extracted with ethanol as solvent at 305 °C and 40 min. produced up to 15.9 wt.% of biodiesel respect to dried biomass processed. Comparable biodiesel yields were obtained using non-renewable organic solvents and a conventional catalytic technology. Thus, ethanol extraction and subsequent supercritical transesterification of H. coffeaeformis oil proved to be technically feasible and environmental friendly technology for the production of biodiesel.

Metal Oxides Derived from Modified Hydromagnesite: Evaluation of Their Catalytic Activity in the Synthesis of Ethyl Biodiesel

AbstractBiofuels are already part of the energy matrix in many countries because of their environmental and economic benefits. Ethyl biodiesel can be produced by various processes, the main one being transesterification of triglyceraldehydes and ethanol. The current technological challenge is to develop efficient heterogeneous catalysts, at low cost, non‐polluting and recyclable to be used in this process. In this context, hydromagnesites Mg5(CO3)4(OH)2⋅4H2O modified with different cations (Ca2+, Zn2+, Cu 2+, Ba2+) and synthesized by co‐precipitation are used as precursors of catalytic oxides calcined at 600 °C. The biodiesel synthesis was conducted at 120 °C for 12 h using 20% (w/w) of catalyst per mass of soybean oil and the ratio 1:20 (mol/mol) of soybean oil/ethanol. The alkyl esters formed were quantified by Gas Chromatography‐Flame Ionization Detection (GC‐FID). The transesterification reaction catalyzed by the reference oxide had a yield of 40%, whereas the best yield (80%) came from the hydromagnesite modified with 20% of Ca2+ which also had the highest basicity/acidity ratio. After use in three reaction cycles, the catalyst with 20% Ca2+ had no significant reduction in efficiency when it was washed with acetone and recalcined at 600 °C, while the untreated catalyst only had a yield of 42%, showing the need for effective reconditioning.

Evidence of enzyme-mediated transesterification of synthetic cannabinoids with ethanol: potential toxicological impact

PurposeSynthetic cannabinoids (SCs) represent a large proportion of novel psychoactive substances on the black market and have caused a number of deaths. Polydrug use including combination of SCs and ethanol could further complicate the toxicological impact. To the best of our knowledge, there have been no reports presenting evidence of transesterification between SCs and ethanol in vitro.MethodsThe in vitro metabolism of the four carboxylate SCs PB-22, NPB-22, 5-fluoro-PB-22 (5F-PB-22), and 5-fluoro-NPB-22 (5F-NPB-22) in the presence of ethanol using human liver microsomes with and without appropriate enzyme inhibitors was studied. Newly identified SC ethyl esters were chemically synthesised and fully characterised. The activity of these SCs and their ethanol transesterification products were assessed using cannabinoid receptor (CB1 and CB2) activation assays.ResultsSCs/ethanol transesterification products were detected and studied using liquid chromatography–high-resolution mass spectrometry. We have shown that the SC ethyl ester formation is mediated by human carboxyl esterase enzymes. The ethyl esters exhibited a reduced activity for the CB receptors compared with their parent compounds.ConclusionsThese novel ethyl esters may be useful additional markers of cannabinoid administration, and especially so if they prove to have longer half-lives than their parent compounds.

Optimization of ethanolic transesterification ultrasound‐assisted from oil mixtures utilizing Box‐Behnken design

Biodiesel is an alternative renewable fuel in the world energy matrix, originating from animal fats and vegetable oils from grains, such as the castor bean cultivated by family farmers in the Brazilian semiarid region. However, the production of biodiesel has some disadvantages. For example, it is difficult to use the same types of oil/fat all year round. In addition, the use of methanol in the biodiesel synthesis and agitation process results in a high consumption of energy. Given this background, this article proposes an alternative biodiesel synthesis using castor oil and peanut oil mixtures, ultrasound-assisted in an ethylic route. The experimental conditions were optimized utilizing a Box-Behnken design. The response variable was a biodiesel yield. In this work, it was possible to reduce the ratio of alcohol to oil and thus reduce the energy consumption and increase the mass yield. This permitted the generation of biofuel with lower production costs. Finally, the response surface methodology leads to operational conditions more suitable for the production of biodiesel. In this work, the best conditions were obtained using 0.50% catalyst concentration, 50/50 castor:peanut oil rate, and 5:1 alcohol:oil ratio. These were moderate and suitable conditions for the synthesis of biodiesel in comparison with the works found in the literature, reaching a high yield of 97.93%.

Enhancement of continuous supercritical biodiesel production: influence of co-solvent types

The aim of this work was to enhance the continuous supercritical biodiesel production process by applying the co-solvent technology. The influence of co-solvent types on the fatty acid alkyl esters (%Ester) or biodiesel content was primarily evaluated. Experiments were performed through the transesterification of palm oil and ethanol in a microtube reactor under the supercritical solvent conditions. Three different polarity levels of co-solvent including tetrahydrofuran, acetone, and iso-propanol were selected. Results indicated that each co-solvent added to the reacting system significantly enhanced the homogeneity of the mixture. The influence of co-solvent type was clearly observed and became small at high reaction temperatures and long residence time. The %Ester was higher than 80% with the addition of any types of co-solvent under the residence time of 3.5 min, co-solvent amount of 20%, reaction temperature of 350 oC, and alcohol-to-oil molar ratio of 23:1, whereas 65.6% of ester content was obtained in the absence of co-solvent under the same operating conditions. The use of acetone as co-solvent provided the highest %Ester; however, further studies in different perspectives such as biodiesel properties, co-solvent separation method, and economic impact should be considered to select the optimized co-solvent for improving the biodiesel production.

Simultaneous development of biodiesel synthesis and fuel quality via continuous supercritical process with reactive co-solvent

This work addresses the simple and effective technique to simultaneously improve biodiesel synthesis and fuel quality. The co-solvent technology was applied to fulfill this purpose. Experiments were performed through the transesterification of palm oil and ethanol in a microtube reactor under the supercritical conditions. The iso-propanol was added in the system and played the roles as a source of reactant to produce isopropyl esters and co-solvent to enhance the homogeneity of the mixture. Upon the application of iso-propanol, high yield of biodiesel was attained under the milder conditions than those reported in the literature in terms of reaction temperature, pressure, residence time, and ethanol-to-oil molar ratio. The influence of operating conditions on the %Ester was investigated and optimization of %Ester was carried out via response surface methodology. The improvement of biodiesel quality was achieved particularly the cloud and pour points which were better quality than that of the conventional biodiesel production.