Triacetin Production Research Articles

Ultrasound assisted interesterification of babassu oil with acetates using acid catalysts for biodiesel and triacetin production

The ultrasound-assisted (US) interesterification of babassu oil with methyl, ethyl and butyl acetates was carried out via acid catalysis for biodiesel production with triacetin as an additive and therefore filling the gap in the field of US induced interesterification reactions. The scanning for the best catalyst was performed using sulfuric, methanesulfonic, p-toluenesulfonic, phosphoric and acetic acids. In order to achieve optimal conditions reactions varied in terms of reactant molar ratio, type and concentration of catalyst, temperature (20 to 50 °C) and ultrasonic energy (120 to 320 W). Using ethyl acetate, reactions were carried out at various molar ratios of oil to acetate (1:12 to 1:72) using sulfuric acid (0.5 % w/wT). The 1:60 experiments were carried out with sulfuric acid concentrations ranging from 0.5 % to 3 % (w/wT). The best catalytic activity was sought using the acids at a concentration of 2.5 %, with 200 W and 1:60. The best catalytic activities were achieved with H2SO4 followed by CH3SO3H and CH3C6H4SO3H and the reactivity follows the ethyl→methyl→butyl trend. The best results were achieved using ethyl acetate with H2SO4 yielding 95.4 % biodiesel plus triacetin with a content of 17.6 % of triacetin in 180 min, which represents an intensification of 25.4 % compared to conventional heating.

Production of triacetin from industrially derived purified glycerol: Experimental proof of concept, kinetic model derivation and validation

This study illustrates the purification of end-of-life crude glycerol from a real biodiesel production process and its conversion into triacetin via esterification with acetic acid. Crude glycerol of 50.9 wt% purity was physicochemically treated to 74.3 wt% reducing the content of ashes (16.1 to 9.8 wt%), matter organic non-glycerol (25.6 to 9.8 wt%) and water (7.4 to 6.1 wt%). For esterification, catalyst screening with commercial ion exchange resins and zeolites showed that Amberlyst 36 attained a triacetin yield of 30.1 % and stability after 5 cycles. An increase of temperature, molar ratio, and catalyst loading positively affected the reaction rates and equilibrium, whereas increasing water content in the feedstock only showed effect on the equilibrium leading to lower triacetin yields. After dismissing mass transfer limitations, a thorough study on the reaction kinetics analysed the effect of temperature (100–130 °C), molar excess of acetic acid (6–12) and catalyst loading (2.5–7.5 wt%) on the concentration profiles. Kinetic models based on Langmuir-Hinshelwood-Hougen-Watson and Eley-Rideal equations were formulated to fit the experimental data, where an Eley-Rideal model accounting only for water adsorption fitted best. Deactivation was also contemplated considering the ash content in the substrate, yet the model does not correlate with a loss of catalytic activity. The activation energies for the forward and backward reactions of the in-series esterification reactions are 38.2 – 45.8 kJ mol–1 and 47.0 – 50.3 kJ mol–1, respectively, and the enthalpy for water adsorption is 28.2 kJ mol–1.

Dielectric Properties During Microwave-Induced Interesterification Reactions for Biodiesel and Triacetin Production

Dielectric Properties During Microwave-Induced Interesterification Reactions for Biodiesel and Triacetin Production

Multifunctional properties of alumina-based graphene nanocomposites as catalysts for esters of glycerol production

The properties of alumina-based graphene nanocomposites were fine-tuned using a directed self-assembly of graphene oxide and metal oxides mediated by a surfactant approach. The resultant nanostructured metal oxides were evaluated in the esterification of glycerol with acetic acid as catalysts for the esters of glycerol production. X-Ray Diffraction (XRD), High-resolution transmission electron microscopy (HRTEM), Raman spectroscopy and Fourier transform infrared (FTIR) spectroscopy measurements of the self-assembled nanocomposites revealed the nanocrystalline γ-Al2O3 phase between the separated graphene lamellar nanostructures. A crumpled monolayered graphene sheet along with well dispersed Ni and Co entities on solid surface appeared by Scanning electron microscopy coupled to energy dispersive X-ray spectroscopy (SEM-EDS) analyses. Electron paramagnetic resonance spectroscopy (EPR) and X-ray photoelectron spectroscopy (XPS) showed Ni2+, Co3+/Co2+and Al3+species and a more reduced surface oxygen species in the self-assembled solids. The addition of basic promoters such as La, Mg or Zn to the composites did not improve the catalytic properties of the solids, but combined with NiCo-alumina-based graphene nanocomposites, they had shown good activities for triacetin production.

Acetylation of glycerol for triacetin production over metal/non-metal doped cobalt ferrite nanocatalysts

Acetylation of glycerol for triacetin production over metal/non-metal doped cobalt ferrite nanocatalysts

Lipozyme® TL IM Biocatalyst for Castor Oil FAME and Triacetin Production by Interesterification: Activity, Stability, and Kinetics

Global climate change and present geopolitical tensions call for novel, renewable, and, ideally, sustainable resources and processes that, in the end, will be integrated in the natural cycles of carbon and water, progressively replacing non-renewable feedstocks. In this context, the production of biofuels and, in consequence, of biodiesel plays a notable role. This work is focused on the production of fatty acid methyl esters (FAME) from castor oil, an abundant non-edible oil, using a sustainable technology approach based on industrial lipases and methyl acetate as a methylating reagent to reduce biocatalyst inactivation. We have selected a stable industrial enzyme preparation to determine its suitability for FAME production: Lipozyme® TL IM (an inexpensive lipase from Thermomyces lanuginosus immobilized by agglomeration in silica gel). Several operational variables affecting the enzyme activity have been studied: methanol excess (6:1 to 13:1), temperature (from 40 to 60 °C), and enzyme concentration (10 and 30% w/w). At all temperatures and reagent ratios, we have also tested the enzyme stability for six cycles, showing its low to negligible inactivation under operational conditions. Finally, a novel multivariable kinetic model has been proposed and fitted to experimental data obtained in a wide experimental range for the first time, showing that direct and reverse in-series reactions are present. We have estimated the values of the kinetic constants and their standard errors, and goodness-of-fit parameters, observing that the kinetic model fitted very reasonably to all retrieved experimental data at the same time.

Упрощенный способ синтеза триацетина – пищевой добавки E1518

Aim. Development of a simplified technology for the production of triacetin – a food additive (E1518) and a water-retaining agent. Materials and Methods. The following main raw materials were used: distilled glycerol 99.5% (LLC «Ukrkhimresursy», Ukraine), glacial acetic acid (LLC «Chemical Alliance», Russia). It is proposed to control the content of unreacted products – glycerol – spectrophotometrically with copper (II), and acetic acid – by acid-base titration. Results. The conditions for the synthesis of triacetin are as follows: the molar ratio of glycerol and acetic acid is 1:6, temperature – 120-125оC, duration – 90 minutes. The distillation of excess acetic acid was carried out at a temperature of 130-140оC for 3 hours, which ensured the receipt of 100% of the product – triacetin, which contains trace amounts of acetic acid. The residual content of acetic acid in the final product is not more than 0.01% of the mass. After distillation, acetic acid is obtained with a concentration of 79-80% (azeotropic mixture). The use of a catalyst – sulfuric acid – negatively affects the color of the final product (from yellow to light brown) and pH (about an 0). The use of a hydrobromic acid catalyst does not lead to a 100% product, but it negatively affects the pH of the finished product (near zero), which requires additional purification of the final product (vacuum distillation) and neutralization, which in turn contaminates the product with inorganic salts. Conclusion. A simplified method for the synthesis of triacetin from glycerol and acetic acid has been developed, which excludes the use of catalysts, vacuum, and sorption purification.

Synthesis and Characterization of Phosphoric Silica Catalyst from Bamboo Leaves for Production of Triacetin

In this research, the bamboo leaf shows promise as an alternative raw material for silica production. This study investigated the performance of heterogeneous catalyst prepared from silica derived bamboo leaf ash after that impregnated with phosphoric acid at ratio various. The catalyst was characterized by X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope Energy Dispersive X-Ray Spectroscopy (SEM-EDS), Brunauer Emmet Teller (BET) and Barrett, Joyner and Halenda (BJH) method and triacetin product analyzed by GC-MS. The optimum condition phosphoric silica catalyst was obtained at phosphoric silica molar ratio of 1:2 and employed in the acetylation of glycerol, respectively. As result, 24 % selectivity for triacetin was obtained in the presence of catalytic amount 5%, molar ratio 1:9 at 100 °C for 4 hours. Bamboo leaf derived phosphoric silica calcined showed high potential to be used as an easy to prepare and high-performance solid catalyst for industrial scale.

Ultrasound-assisted Esterification of Glycerol for Triacetin Production

Glycerol is a by-product of biodiesel production. So far, glycerol has not been used optimally. An alternative product that can be produced from glycerol is triacetin through the esterification process. Research on the review of reaction kinetics to determine the optimum conditions of the reaction still limited. Previous study also reported that the esterification process requires quite a long reaction time. Therefore, in this study ultrasonic technology will be used to accelerate the reaction of glycerol esterification with acetic acid using sulfuric acid catalyst. The purpose of this study is to study the effect of ultrasonic technology on the conversion of esterification of glycerol/acetic acid, and to observe the kinetic study of triacetin production. To answer this goal, this study uses a set of ultrasonic devices as a substitute for the esterification of conventional models. The greatest conversion results are obtained when the reaction temperature is 1000C with a mole ratio of glycerol/mole of acetic acid 1/8. The use of ultrasonic technology in theory should have a greater impact on conversion results. The reaction order obtained is order 2 with the largest k value in the mole ratio of glycerol: acetic acid 1: 8 which is 0.0006 (l.mol−1menit−1). Due to the variation of moles ratio, the ratio at 1/6 and 1/4 did not show significant changes of reaction rate, the changes are constant for both first and second order reaction. But at the mole ratio of 1/8, the reaction rate constant shows a significant different for temperature changes.

Optimization of spark-ignition engine characteristics fuelled with oxygenated bio-additive (triacetin) using response surface methodology

Biodiesel, as an alternative fuel, has gained wide interest in recent years. However, despite the countless benefits, the enormous generation of glycerol-waste and higher production costs have been causing severe challenges to both the environment and the biodiesel economy’s survival. With the focus on maintaining its sustainability, the proper valorization of the crude glycerol is of vital importance. The objective of the present study is to harness and transform glycerol (a by-product of biodiesel) to triacetin and utilize it further as a fuel additive for spark ignition (SI) engine. Triacetin is a valuable compound of bio-based origin, having good anti-knock properties and higher oxygen content. Test fuels containing different blends of gasoline, methanol and triacetin were prepared and compared with neat gasoline. The Response Surface Methodology (RSM) based multi-objective technique was selected to optimize the engine output parameters like BTE, CO, CO2, HC and NOx emissions. The results indicate that the engine operating at 1.17 kW brake power and containing 90.73% gasoline, 4.94% methanol and 4.31% triacetin (by vol.) were found to be the optimum input parameter combinations which shows maximum BTE and lowest engine exhaust emissions as compared to other fuel blends. The estimated economic analysis of small-scale plants was also carried out, revealing that about 4.2% of revenue per kg of triacetin selling can be generated by running biodiesel and triacetin production analogously. Among various alternatives probed, the acetylation of glycerol to triacetin appears to be the ideal solution. It can serve the multiple purposes of reducing vehicular emission and improving the economic viability of burgeoning biodiesel industries and creating new opportunities, livelihoods, and jobs for humanity.

Esterification of Glycerol with Acetic Acid in Bioadditive Triacetin with Fe<sub>2</sub>O<sub>3</sub>/Activated Carbon Catalyst

Esterification and transesterification processes for biodiesel production generate glycerol which is possible to be converted into triacetin. It is an actractive bioadditive for increasing octane number of fuel. The production of this bioadditive in a biodiesel plant also increases the revenue as raw material comes from biodiesel process production as by-product.This study examines the effects of catalyst concentration and temperature on triacetin production using glycerol from esterification process and acetic acid at volume ratio of 1:3 as raw materials. An activated charcoal as catalyst is activated with sulfuric acid at concentration of 2% and 3% (w/w). The esterification temperatures are varied at 90 and 100°C and the reaction time is set for 3 hours. The samples are taken frequently at certain interval times of 15, 30, and 60 minutes for chemical analysis using Gas Chromatography Mass Spectometry. It is observed that using 2% and 3% (w/w) of catalysts at 90°C and 60 minutes reaction time converts 41.037% and 57.441% of glycerol respectively.

Interesterification of grease trap waste lipids using methyl acetate under supercritical conditions

The production of fatty acid methyl esters (FAMEs) and triacetin (TA) from the lipids of the grease trap waste (GTW) using methyl acetate (MA) under pressurized conditions was investigated. The experiments evaluating the effect of temperature (275–350 ºC), residence time (10–30 min), addition of water (2.5–10 wt% in relation to the MA), free fatty acid (FFA) content (25 and 50 wt% in the GTW) in the formation of FAMEs and TA. The results show that an increase in temperature favors the FAME production in the first 10 min of reaction and from 20 min onward the yield increases at 300 °C and decreases at 325 °C. The TA production was higher in 30 min at 300 ºC. The addition of up to 5 wt% water (in MA) showed a similar yield, while higher contents leads to a reduction in the FAME production after 30 min. The use of a feedstock with up to 50 wt% (by mass) of FFAs has little influence on the formation of FAMEs and leads to lower amounts of TA. The reaction with MA (5 wt% of water) provided a sample with 57 % of FAMEs and 1.4 wt% of TA.

Use of the Product from Low Pressure Extraction (Crambe Seed Oil and Methyl Acetate) for Synthesis of Methyl Esters and Triacetin Under Supercritical Conditions

AbstractMethyl esters (ME) and triacetin production from the supercritical interesterification of the product from low pressure extraction (crambe seed oil and methyl acetate) are evaluated. Reactions are conducted at 300–375 °C for different residence times, at 20 MPa, and under these conditions the thermal stability of triacetin is evaluated. The effect of the free fatty acid (FFA) concentration (in oil) is determined. An increase in temperature favors the formation of ME and triacetin at shorter reaction times. At 375 °C, after 15 min a drop in the ME yield is observed and triacetin is not detected. A reduction in the triacetin concentration (reaching ≈99%) is observed at 375 °C. High FFA concentration (in oil) initially provided higher product generation, however, after 15 min no influence is observed. The highest ME yield (≈60%) is obtained at 300 °C, along with 1.22 wt% triacetin and ≈5.0 wt% unreacted compounds.Practical Applications: This paper reports new experimental data on an integrated process for the production of methyl esters from low pressure extraction (crambe seeds and methyl acetate) and supercritical reaction of the extraction mixture. The technique used allows the removal of a high quantity of oil from good quality crambe seeds. The viability of applying the integrated process to obtain oils with a high content of free fatty acids is verified, promoting the obtainment of relatively simple methyl esters. The procedure does not require oil purification and solvent recovery prior to the reaction.

Triacetin production using SiO2-H3PO4 catalysts derived from bamboo leaf biomass waste for esterification reactions of glycerol and acetic acid

Increasing the demand for renewable fuels especially for biodiesel has the effect of increasing by products during biodiesel production. Therefore, the efforts made to make biodiesel by products in the form of glycerol become more economic value, then further processing is carried out into biofuel additives. One of the biofuel additives that can be synthesized from glycerol is triacetin. In this study, the production of triacetin compounds was carried out through an esterification reaction using calcined SiO2-H3PO4 catalyst originating from bamboo leaf biomass waste so that glycerol conversion, concentration and selectivity of the best triacetin products from various reaction variables were obtained. The esterification process is carried out by reacting glycerol and acetic acid with a mass ratio of glycerol: acetic acid which is 1 : 9 at a temperature of 100 ± 5°C to produce the main product triacetin. The influence of various process variables such as catalyst type, catalyst weight, and reaction time on glycerol conversion was observed in this study. The best conditions produced in this study were the highest conversion of 100% glycerol, the concentration of triacetin products 18.53%, and selectivity of triacetin products 22.84% with catalyst type SiO2-H3PO4 1 : 2 (M/M), catalyst weight 5% from glycerol weight, reaction time of 4 hours, and stirring speed of 300 rpm.

Triacetin Production by Selective Esterification of Glycerol over Activated Zeolite and Lewatite as Catalyst

The conversion of glycerol as by product of biodiesel manufacture into value-added product was studied. Esterification of glycerol with acetic acid to triacetin was carried out using activated zeolite and Lewatite as catalyst A selective method for triacetin synthesis was developed to investigate the effect of molar ratio of glycerol to acetic acid (1:6, 1:7 and 1:8). The conversion values at the reactant mole ratio were subsequently 66.91%, 73.36% and 73.16%, while the selectivity obtained was 7.67%, 9.66% and 10.61% respectively. From these results, it can be concluded that the highest conversion was obtained at a reactant mole ratio of 1: 7 and the highest selectivity was obtained at a reactant mole ratio of 1: 8. The result of selectivity with various catalyst type shows that the Lewatit catalyst produces a higher selectivity than the use of activated natural zeolite as a catalyst.

Single-pot template-free synthesis of a glycerol-derived C–Si–Zr mesoporous composite catalyst for fuel additive production

The C–Si–Zr material synthesized from bio-derived waste glycerol, ZrO(NO3)2 and TEOS exhibits excellent catalytic activity for tri-acetin production from low-value glycerol.

Production of Triacetin by Microwave Assisted Esterification of Glycerol Using Activated Natural Zeolite

Triacetin, an alternative biodiesel additive, was prepared by esterification of glycerol with acetic acid in the presence of chemically activated natural zeolite. The esterification was carried out in a small reaction flask under microwave irradiation. The catalyst was characterized for its morphology by SEM and its chemical composition by X-ray Diffraction (XRD). The Scanning Electron Microscopy (SEM) micrograph indicates improved surface area of the zeolite, while the XRD analysis shows an increase in Si/Al ratio from natural zeolite to 6.042 and its crystallinity value of 12.23%. The Fourier Transform Infra Red (FTIR) analysis obtained showed that microwave-heated samples have an esters group spectrum of triacetin at 1702 cm-1. The conversion value of glycerol was more than 95% at molar ratio of the reactants 1:9 and catalyst loading of 3%. The selectivities for monoacetin, diacetin and triacetin were 80.1%, 15.4%, and 4.5% at 60 minutes, and 43.0%, 48.6%, and 8.3% at 90 minutes. It shows that the conversion took place in consecutive steps and the use of microwave allows the reaction proceeding at milder condition.

Triacetin Production From Glycerol Using Heterogeneous Catalysts Prepared From Peat Clay

Glycerol, an abundant by-product of biodiesel production, is urgently considered to increase its usage. Triacetin produced from glycerol is an important material, used in polyester, cryogenics, cosmetics and as a biodiesel additive. Using homogeneous catalysts in triacetin production involves high product separation costs. The purpose of this study is to synthesize heterogeneous catalysts based on alumina and silica from peat clay for use in the production of triacetin from glycerol. The conversion of glycerol for triacetin production using such alumina and silica catalysts yielded levels of 82.7% and 87.4%, respectively. These values were greater than the conversion value of 71.2% using a sulfuric acid homogeneous catalyst. An optimum conversion of 91% was obtained at the mole ratio of glycerol to acetic acid of 8.9. The potential heterogeneous catalysts were confirmed by the results of SEM, XRD and BET characterization. Therefore, the production of triacetin using heterogeneous silica catalyst could be an alternative approach in commercial processes which currently using homogeneous catalysts.

Esterification of Glycerol with Acetic Acid Using Nitrogen-Based Brønsted-Acidic Ionic Liquids

Glycerol esterification with acetic acid produces a mixture of mono, di, and triacetins, which are commercially important value-added products with a wide range of industrial uses including their application as fuel-additives, thus contributing to environmental sustainability and economic viability of the biorefinery concept. Glycerol esterification with acetic acid was studied using a range of nitrogen-based Bronsted-acidic ionic liquids. Cost-effective and easily synthesized Bronsted-acidic ionic liquids based on alkyl-pyrrolidone and alkyl-amine cations were synthesized and characterized using ¹H NMR spectroscopy. The catalytic activity of the Bronsted-acidic ionic liquids produced were investigated for the production of di and triacetin from glycerol and acetic acid. Amongst all ionic liquids evaluated in this study, N-methyl-2-pyrrolidinium hydrogen sulfate [H-NMP][HSO₄] was found to be the most active and cost-effective catalyst. The effect of significant reaction parameters on selectivity to the trisubstituted product, triacetin, was modeled using a design of experiment (DoE) approach with a response surface methodology involving a central composite design. The esterification process was optimized to maximize the production of triacetin. Optimizing the process this way naturally leads to lower levels of mono and diacetin. Amongst the reaction parameters evaluated, temperature had the greatest influence on product selectivity, followed by the glycerol to acetic acid molar ratio, and the model also showed dependence on the synergistic interaction between the temperature and mole ratio. It is worth noting that agitation speed had minimal influence on product selectivity. Under optimized reaction conditions, >99% glycerol conversion was achieved with 42.3% selectivity to triacetin, and a combined di and triacetin selectivity of >95% within 1 h.

BIOFUEL VIA INTERESTERIFICATION OF RAPESEED OIL WITH METHYL ACETATE IN PRESENCE OF POTASSIUM t-BUTOXIDE/THF

Transesterification does not allow to make full conversion of oil to biodiesel because the by-product glycerol cannot be included in the composition of biofuel. Interesterification constitutes a full conversion process with production of triacetin (TA) instead of glycerol, which can be included in the composition of biofuel and allows to increase its yield. Both interesterification and transesterification effectively occur only in presence of catalysts. Results of the investigation of heterogeneous and homogeneous catalysts indicate the superior importance of catalyst solubility in starting reaction mixture. Partial solubility can remarkably lower the activity of homogeneous catalyst and extremely increase that of formally heterogeneous one. The reaction mixture of interesterification reaction is less polar than that of transesterification, and potassium tert-butoxide (t-BuOK) should be more appropriate catalyst for interesterification than sodium methoxide which is used in most cases. The catalytic system t-BuOK/t-BuOH substantially increases the yield of TA and changes the properties of obtained biofuel. Whereas the content of the TA in the interesterification reaction mixture does not achieve the same level from the theoretically predicted as the FAME, the occurrence of side reaction between t-BuOH and TA cannot be excluded. This paper presents a study of the interesterification of rapeseed oil in presence of catalytic system t-BuOK/THF (catalytic system without alcohols) with the aim of establishing the influence of aprotic tetrahydrofuran to the proceeding the reaction, composition of reaction mixtures and their fuel properties. Obtained results show that the absence of alcoholic hydroxyl groups in the catalytic system insufficiently increases the activity of catalytic system but fails to increase the yield of FAME.