Catalyst For Transesterification Research Articles

Deactivation Mechanism of an Ionic Liquid Catalyst in Transesterification to Dimethyl Carbonate

The catalytic activity of ionic liquid catalyst decreased during the transesterification of propylene carbonate (PC) with methanol to dimethyl carbonate (DMC). The interaction between the strong basic sites of ionic liquid catalyst and carbonyl compounds of PC and/or DMC was considered to attribute to this deactivation. The presence of H2O accelerated this process by the formation of OH–. The strong basic ionic liquid reacted with the trace amount of H2O in the reaction system to generate OH–, and then the generated OH– reacted with the carbonyl structure in PC and/or DMC to form inactive compound HCO3–, resulting in the deactivation of the ionic liquid catalyst. A plausible mechanism was proposed for the deactivation of the ionic liquid catalyst in this reaction.

Influence of desilication route of ZSM-5 zeolite in mesoporous zeolite supported calcium oxide catalyst for biodiesel production

The application of calcium oxide (CaO) as transesterification catalyst for biodiesel production is restricted as there is a high tendency for the calcium (Ca2+) active species to be leached out during the reaction. To overcome this problem, CaO was supported with mesoporous zeolite. A series of mesoporous zeolite supports were prepared via 3 different desilication routes, which are conventional desilication, desilication in the presence of pore directing agent and surfactant-assisted desilication method. The catalytic efficiency of the synthesized catalyst, which are CaO/Zeo, CaO/Zeo-NaOH, CaO/Zeo-TPAOH and CaO/Zeo-CTAB catalyst, in the transesterification of waste cooking oil (WCO) was evaluated. Results revealed that the surfactant-assisted desilication route demonstrates the partial incorporation of the dissolved Al species into the zeolite framework and thus led to highly crystalline material. An obtained high mesoporosity of the zeolite support through this route caused the high dispersion of CaO species in the pores of zeolite support. As a results, the CaO/Zeo-CTAB catalyst exhibited the best performance with 89% biodiesel yield, due to strong acidic and basic properties together with high surface area. The catalyst also showed the higher resistance against Ca2+ active sites leaching by restraining the agglomeration, due to the stronger interaction between CaO and zeolite. The optimum reaction conditions were found to be 4 wt% catalyst dosage, 4 h reaction time, 5:1 methanol to oil molar ratio and 65 °C reaction temperature. The CaO/Zeo-CTAB catalyst could be reused for 6 consecutive runs without significant loss in biodiesel yield and displayed an excellent tolerance to high free fatty acid (FFA) feedstock. For the final remark, these results suggest that the surfactant-assisted desilication is an efficient route for the production of mesoporous zeolite for catalyst support.

Sodium doped zirconia drenched SBA-15 as a reusable solid catalyst for concurrent esterification and transesterification of low-quality oils

Sodium doped zirconia impregnated SBA-15 has been prepared without using hydrothermal treatment trailing the wet impregnation route. The prepared catalyst has been characterized by employing various techniques viz., BET for surface area analysis, SEM for morphological study, XPS for element oxidation state determination. It was found that catalyst seized both acidic and basic sites therefore, successfully employed for one-pot or concurrent esterification and transesterification of virgin cottonseed oil and high FFA containing vegetable oils. Under optimum reaction conditions of catalyst concentration of 10 wt% with respect to weight of oil, MeOH/oil molar ratio of 30:1 and at 65 °C reaction temperature, the catalyst could confer > 98 % fatty acid methyl ester yield within 3 h of reaction duration. Regeneration study advocated that the catalyst may well be recycled for 5 successive cycles without any significant trouncing of activity and even yielded 86% fatty acid methyl esters during 6th cycle. Keywords: Heterogeneous catalysts, mesoporous, basicity, acidity, transesterification, thermodynamic parameters

An experimental study on synthesis of ternary biodiesel through potassium hydroxide catalyst transesterification

AbstractThe novelty of this study is synthesis fuel of biodiesel from the Brassica napus seed oil (BN‐B), Linum usitatissimum seed oil (LU‐B) and diesel to improve the performance of SCDE and minimize the CO2 emissions. BN‐B and LU‐B were produced using a 0.1 N potassium hydroxide catalyst and methanol to synthesis biodiesel from B. napus and L. usitatissimum seed oil. The glycerine and biodiesel are separated using the transesterification filtration process. The research was carried out without any modifications with the objective of analyzing performance and emissions in a SCDE at variable load and constant speed. SCDE investigates the impact of five different triple combinations of BN‐B and LU‐B blended with diesel. The experiments yielded the following results, B1‐B and B2‐B have calorific values of 42.2 and 41.6 MJ/kg, respectively. The fuel consumption of the triple blend combination was lower than that of the diesel at full load and constant speed. The triple blend combination emits less nitrogen dioxide (NO2) and carbon monoxide (CO) than diesel, according to the results of the emission tests.

Selected acid and basic functionalized ordered mesoporous materials as solid catalysts for transesterification of canola oil: A comparative study

This study investigates the preparation and application of mesoporous silica-supported basic and acidic catalysts in transesterification. Mesoporous silicas of SBA-15 and MCF type were prepared and modified by post-synthesis with organic moieties (amine and sulfonic). The obtained supports and catalysts were characterized by N2 adsorption, IR spectroscopy, MAS NMR, SEM, and TEM techniques. The results show that several active groups attached to the SBA-15 and MCF silica channels do not lead to the collapsing of the characteristic open structure of the mesoporous sieves. The investigated catalysts exhibit high activity and selectivity in the transesterification of canola oil. The SBA-15-phenyl-SO3H one shows the highest conversion (84.6%) after 6 h (at 150 °C), which is comparable to the activity of H2SO4. The selectivity towards fatty acid methyl esters was noted at the level of 60.6% (after 6 h of reaction).

Effect of Sodium Hydroxide on a Bentonite Support as Catalyst for Transesterification of Waste Cooking Oil into Biodiesel

Effect of Sodium Hydroxide on a Bentonite Support as Catalyst for Transesterification of Waste Cooking Oil into Biodiesel

A novel bioderived AB2‐type monomer from castor oil derivative for the preparation of fully biobased hyperbranched polyesters

AbstractDesigning biobased hyperbranched polyesters from vegetable oil has been attracting considerable interests from academic industrial communities. Herein, a novel fully biobased hyperbranched polyester (HBPE) was prepared by self‐condensation of AB2‐type bioderived monomer based on methyl ricinoleate (MR), a castor oil‐derived renewable chemical. The reaction conditions were optimized to obtain the AB2‐type monomer in a high conversion ratio (up to 87%). The self‐condensation of AB2‐type monomers was carried out in the presence of two kinds of transesterification catalysts (Ti(OBu)4 versus Zn(Ac)2), among which Ti(OBu)4 was found to be more efficient one and yield higher molecular weights in the range of 5800~11,500 g/mol. The resulting HBPEs were characterized in terms of Fourier transform infrared spectroscopy, nuclear magnetic resonance, differential scanning calorimetry, and thermogravimetric analysis. The degree of branching was calculated to be 0.33~0.39. Thermal analysis revealed that the as‐prepared HBPEs were amorphous with tunable glass transition temperatures ranging from −44.8 to −24.6°C. All the prepared HBPEs exhibited good thermal stability with the maximum onset decomposition temperature (Tonset) up to 294.6°C. These structural features and properties of resulting biobased HBPEs enabled them to act as a potential ‘greener’ additive for polymers.

Synthesis of different heteropoly acid catalysts for transesterification of bio-derived glycerol to produce oxygenated fuel additive for energy utilization

Synthesis of different heteropoly acid catalysts for transesterification of bio-derived glycerol to produce oxygenated fuel additive for energy utilization

Performance of Citric Acid as a Catalyst and Support Catalyst When Synthesized with NaOH and CaO in Transesterification of Biodiesel from Black Soldier Fly Larvae Fed on Kitchen Waste

Current research and development to lower the production cost of biodiesel by utilizing feedstock derived from waste motivates the quest for developing catalysts with high performance in transesterification. This study investigates the performance of citric acid as a catalyst and support catalyst in transesterification of oil from black soldier fly (Hermetia illucens) larvae fed on organic kitchen waste. Two catalysts were prepared by synthesizing citric acid with NaOH and CaO by a co-precipitation and an impregnation method, respectively. The design of the experiment adopted response surface methodology for the optimization of biodiesel productivity by varying: the percentage loading weight of citric acid, the impregnation temperature, the calcinating temperature and the calcinating time. The characteristic activity and reuse of the synthesized catalysts in transesterification reactions were investigated. The morphology, chemical composition and structure of the catalysts were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray fluorescence (XRF) and X-ray diffraction (XRD). High citric acid loading on NaOH and a small amount of citric acid on CaO resulted in improved dispersion and refinement of the particle sizes. Increasing citric acid loading on NaOH improved the CaO and SiO2 composition of the modified catalyst resulting in higher biodiesel yield compared to the modified CaO catalyst. A maximum biodiesel yield of 93.08%, ±1.31, was obtained when NaOH was synthesized with a 130% weight of citric acid at 80 °C and calcinated at 600 °C for 240 min. Comparatively, a maximum biodiesel yield of 90.35%, ±1.99, was obtained when CaO was synthesized with a 3% weight of citric acid, impregnated at 140 °C and calcinated at 900 °C for 240 min. The two modified catalysts could be recycled four times while maintaining a biodiesel yield of more than 70%.

Application of dolomite as solid base catalyst for transesterification of rapeseed oil with butanol

The article presents the results of studies on the transesterification of rapeseed oil with butanol using a heterogeneous catalyst (0.315–0.1 mm) of the dolomite calcined at 850 °C. Experimental plan was prepared and results analyzed using response surface methodology. Interaction of four independent variables were analyzed and presented in the article. It was found that the biggest influence on ester yield have the temperature and the duration of the reaction. After optimizing the process, it was found that in 8 h the highest ester yield of 94.55 wt% is obtained using 5.24 wt% of dolomite, at 110 °C and 13.71:1 M ratio of butanol to oil.

Evaluation and kinetic study of alkaline ionic liquid for biodiesel production through transesterification of sunflower oil

Biodiesel production is performed in the industry by alkaline transesterification of oils with a low amount of free fatty acids. In order to reduce the disposal of conventional catalysts used industrially, ionic liquids (ILs) have been studied to be applied as catalysts in transesterification since they can be recovered and reused in subsequent reaction cycles. In this work, the ionic liquid choline hydroxide (ChOH) was successfully applied as a catalyst for the transesterification reaction of triacylglycerols present in sunflower oil with methanol. A kinetic modeling study under the specific conditions of 2 wt% catalyst dosage, 1:10 oil/methanol molar ratio, for 0–120 min at 35–65 ℃ was conducted, and liquid–liquid extraction with water/butanol was evaluated as a process to recover the IL. A 95.0% ester yield content was achieved in this work for a short reaction time (30 min). Furthermore, the results of the kinetic study demonstrated that a first-order model was the best fit for the reaction with a rate constant (k) estimated as 0.1182 min−1 and activation energy (Ea) of 13.64 kJ/mol. For the tested conditions, the complete recovery of the IL using liquid–liquid extraction did not occur since it is noted the presence of ChOH in both phases.

Large particle spherical poly-ionic liquid–solid base catalyst for high-efficiency transesterification of ethylene carbonate to prepare dimethyl carbonate

Large particle spherical poly-ionic liquid–solid base catalyst (PILs-FL) was synthesized by suspension polymerization. This catalyst was characterized by SEM-EDS, T.G., FT-IR and BET-BJH. The characterization results show that PILs-FL has a specific core structure, a certain size of surface area (168.7 m2/g), pore size(6.3 nm), and high alkalinity (2.6 mmol/g). The catalyst performance was evaluated by vinyl carbonate and methanol reaction to form dimethyl carbonate (DMC). The reaction conditions were optimized in detail. The optimal reaction conditions were that the molar ratio of methanol and ethylene carbonate 9:1, catalyst dosage 3 wt%, reaction time 5 h, and temperature 90 °C, The yield of DMC was up to 93.7% under the optimal reaction conditions. In addition, The catalyst is separated very easily by simple filtration. The catalyst activity hardly decreased after being reused five times, and the catalyst shape was not destroyed, which meant that the catalyst had a high mechanical strength.

Green Synthesized ZnO Nanoparticles as Biodiesel Blends and Their Effect on the Performance and Emission of Greenhouse Gases.

Pollution and global warming are a few of the many reasons for environmental problems, due to industrial wastes and greenhouse gases, hence there are efforts to bring down such emissions to reduce pollution and combat global warming. In the present study, zinc oxide nanoparticles are green synthesized using cow dung as fuel, through combustion. Synthesized material was characterized by FTIR, XRD, UV, and FESEM. The as-prepared ZnO-GS NPs were employed as a transesterification catalyst for the preparation of biodiesel from discarded cooking oil. The biodiesel obtained is termed D-COME (discarded cooking oil methyl ester), which is blended with 20% commercial diesel (B20). Additionally, this blend, i.e., B20, is further blended with varying amounts of as-prepared ZnO-GS NPs, in order to ascertain its effects on the quality of emissions of various greenhouse gases such as hydrocarbons, COx, NOx. Moreover, the brake thermal efficiency (BTHE) and brake specific fuel consumption (BSFC) were studied for their blends. The blend (B20) with 30 mg of ZnO-GS, i.e., B20-30, displays the best performance and reduced emissions. Comparative studies revealed that the ZnO-GS NPs are as efficient as the ZnO-C NPs, indicating that the green synthetic approach employed does not affect the efficiency of the ZnO NPs.

Vitrimerization of Crosslinked Unsaturated Polyester Resins: A Mechanochemical Approach to Recycle and Reprocess Thermosets.

Unsaturated polyester resins (UPRs) are expansively used in different applications and recycling the significant amounts of UPR waste is still a universal problem. Vitrimerization is a feasible, environmental‐friendly, cost effective, and operative method, which can be used for recycling the crosslinked UPRs. In this method, the thermoset permanent network is changed into a dynamic network similar to the vitrimer‐type polymers. The results show that the existence of a transesterification catalyst in the system significantly enhances the efficiency of vitrimerization. The vitrimerized UPR thermosets can be reprocessed three times with mechanical properties comparable to the initial UPR. The results show that the excess of external hydroxyl groups in the system can prevent the formation of zinc ligand complexes in the network and consequently reduce the crosslinked density and mechanical properties of vitrimerized samples. The vitrimerized thermoset powder can be reprocessed through injection molding, extrusion, and compression molding which are conventional thermoplastic processing techniques. The unrecyclable UPR thermoset wastes can be recycled and reused through vitrimerization with the least loss in mechanical properties.

Metal Oxide Doped Egg Shell-Fly Ash Composite: An Effective Catalyst for Transesterification of Waste Oil

Biodiesel is a promising alternative for fossil fuels as it is a renewable source of energy and is considered a green fuel. Generally used method for preparation of biodiesel is catalytic transesterification. Fly ash, an inorganic waste, is a major environmental contaminant. The utilization and safe management of this material is the need of the hour. In this short communication, we report a composite of fly ash and eggshell modified with zinc oxide (ZEF) as a low-cost, efficient, and reusable heterogeneous base catalyst for transesterification reaction of waste cooking oil. The catalyst was prepared by the wet impregnation method and was characterized by FT-IR, XRD, and SEM techniques. Catalytic performance was checked in biodiesel preparation. Conditions like catalyst loading, oil: methanol ratio, temperature, and time were optimized. Product formation was confirmed by the GC analysis.

Oligonucleotides containing abasic threoninol-terpyridine residues as potential artificial ribonucleases

Artificial ribonucleases, also known as synthetic ribozymes, were synthesized with an internal, stereochemically-pure, abasic threoninol backbone-residue to which the RNA transesterification catalyst copper (II) terpyridine was covalently linked. These oligonucleotide conjugates were constructed to determine if the stereochemistry of the abasic threoninol backbone residue influences the transesterification rate of complementary RNA oligonucleotides. Following synthesis, these compounds were reacted with complementary 28-mer and 159-mer RNA substrates and their relative transesterification efficiencies were determined. The transesterification kinetics were also compared with previously synthesized oligonucleotides that incorporated copper (II) terpyridine via a serinol-residue. It was determined that oligonucleotides that contained copper (II) terpyridine linked via a (2S,3S)-threoninol backbone were more efficient at RNA transesterification than their (2R,3R)-stereoisomer counterpart.

Sulfated TiO2 supported molybdenum-based catalysts for transesterification of Jatropha seed oil: Effect of molybdenum species and acidity properties

A series of sulfated TiO2 supported Mo (xMo/1.5ST) catalysts were synthesized successfully and evaluated for the transesterification of Jatropha seed oil (JO) to biodiesel. Extensive characterization exhibits that the well dispersed Mo oxide species, with Mo6+ and Mo5+ oxidation states, were formed on the surface of the sulfated TiO2. The results indicate the presence of many sulfates species leads to the reduction of Mo6+ species to Mo5+ species. Furthermore, the catalytic activity of the xMo/1.5ST catalysts gradually increases with the increase of Mo-loading, although the sulfates content and the total acid intensity decrease. The transesterification process was fully investigated, and the 10Mo/1.5ST shows the highest yield of biodiesel of up to 97.42%. Additionally, the possible mechanism for the JO transesterification over Mo/1.5ST was described, and the fuel properties of the as-synthesized biodiesel conformed to the current international standards.

Enhanced production of biodiesel using nanomaterials: A detailed review on the mechanism and influencing factors

The deterioration of fossil fuel supplies, combined with growing environmental concerns about fossil fuel extraction and consumption, has prompted worldwide communities to focus on renewable energy. Biodiesel production from various biomass feedstock is identified as an environmentally friendly and sustainable alternative. The application of nanomaterials as catalysts in the synthesis of biodiesel has enhanced the yield due to the selectivity. This review article is focused on the applications of potential nanoparticles in biodiesel production and their mechanism of action. The effect of operating variables, namely nanomaterial type, concentration, temperature, methanol to oil ratio, and water content on biodiesel production have been summarized. Under microwave-assisted transesterification, both sodium hydroxide and strontium oxide catalysts, produced highest yield (99%). For calcium oxide nanocatalyst, the highest biodiesel conversion obtained was 98.2% through microwave-assisted transesterification method of waste cooking oil. The optimal conditions for such a high conversion yield were methanol to oil ratio, reaction temperature, time, and catalyst loading of, 1:8, 65 °C, 76 mins, and 4 wt% respectively. The maximum biodiesel conversion yield achieved using KOH nanocatalyst was 96.44% in a microwave-assisted transesterification of waste cotton-seed cooking oil, at optimum conditions of 9.6 min, 0.65 wt% catalyst loading, and 7:1 methanol: oil ratio, respectively. Future perspectives on nanocatalysis for biodiesel production are explained.

Facile and efficient formation of stereocomplex polylactide fibers drawn at low temperatures

Stereocomplex polylactide (SC-PLA) provides an effective route to improve heat-resistance through the formation of SC-PLA crystallites driven by hydrogen bonding interactions between poly(l-lactide) (PLLA) and poly(d-lactide) (PDLA). Great progress has been made in low molecular-weight SC-PLA compounds. However, the development of strategies for exclusive stereocomplexation in high molecular-weight (high-MW) PLLA/PDLA racemic blends quenched from isotropic melt remains challenging. In this study, in-situ reactive melt-spinning of commercially available high-MW PLLA/PDLA blend with a new transesterification catalyst (i.e., sodium octanoate in MB) was devised as an effective strategy to prepare blends containing stereo-block PLA (sb-PLA) copolymers. As a result, the sb-PLA copolymers restricted phase separation and further promoted relatively weak CH3⋯ OC hydrogen bonding interactions, along with the development of the exclusive SC-PLA crystallites with low crystalline thickness (Lc) in PLLA/PDLA/MB blend fibers drawn at low temperatures (≤102 °C). In contrast, extremely limited transesterification reaction in PLLA/PDLA melt led to the phase separation and the resultant separate domains of PLLA or PDLA restricted the occurrence of the CH3⋯ OC hydrogen bonding interactions in the PLLA/PDLA blend fibers drawn at low temperatures (≤120 °C). Only when the PLLA/PDLA blend fibers were drawn at a high temperature (198 °C), the strong CH3⋯ OC hydrogen bonding interactions could be formed, along with the formation of the exclusive SC-PLA crystallites with high Lc. These findings provide a facile and effective strategy to develop industrial-scale PLA fibers containing the exclusive SC-PLA crystallites with improved heat-resistance.

Preparation of zinc oxide graphted nickel incorporated mesoporous SBA-16 doped graphene oxide: An efficient catalyst for transesterification of waste edible oil to biodiesel and photocatalytic degradation of organic dyes

Graphene-based composite materials a wide range of applications, including the production of electronic components and capacitors, as well as adsorption and catalysis. In this work, the ZnO/Ni-SBA-16@GO nanocatalyst was applied to synthesized biodiesel from waste edible oil (WEO) as an efficient and easily available source. The said nanomaterial was applied for the degradation of methylene blue (MB) and methyl orange (MO). The catalyst was characterized by HRTEM, XRD (small angle and wide angle), SEM, EDX, BET, N2 adsorption/desorption isotherm, and TGA. The findings illustrated that the nanostructure has well-controlled pore diameter (4.0 nm) and prominent surface area (735 m2/g). Furthermore, it was possible to reuse the catalyst up to five times; with the results indicating that the catalyst's catalytic activity was sufficient for the synthesis of WEO biodiesel for up to three cycles before diminishing. The present study used a centralized composite approach to look at the influence of numerous features on biodiesel synthesis in order to discover the optimal conditions for biodiesel production. According to the findings, the maximum biodiesel conversion yields 98% had been obtained during a 7-hour reaction time at a temperature of 70 °C. The nanostructure has also been worked as a photocatalyst to degrade MB and MO. According to the statistics, more than 90% of both dyes were degraded in less than 40 min.