Catalyst For Transesterification Research Articles

Chemoenzymatic Dynamic Kinetic Asymmetric Transformations of β-Hydroxyketones.

Herein we report on the development and application of chemoenzymatic Dynamic Kinetic Asymmetric Transformation (DYKAT) of α‐substituted β‐hydroxyketones (β‐HKs), using Candida antartica lipase B (CALB) as transesterification catalyst and a ruthenium complex as epimerization catalyst. An operationally simple protocol allows for an efficient preparation of highly enantiomerically enriched α‐substituted β‐oxoacetates. The products were obtained in yields up to 95 % with good diastereomeric ratios.

Synthesis and Characterization of Heterogeneous Solid Acid Catalyst from Alstonia scolaris Stalks for Biodiesel Production using Waste Cooking Oil

Background: Waste biomass derived reusable heterogeneous acid based catalysts are more suitable to overcome the problems associated with homogeneous catalysts. The use of agricultural biomass as catalyst for transesterification process is more economical and it reduces the overall production cost of biodiesel. The identification of an appropriate suitable catalyst for effective transesterification will be a landmark in biofuel sector Objective: In the present investigation, waste wood biomass was used to prepare a low cost sulfonated solid acid catalyst for the production of biodiesel using waste cooking oil. Methods: The pretreated wood biomass was first calcined then sulfonated with H2SO4. The catalyst was characterized by various analyses such as, Fourier-transform infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDS) and X-ray diffraction (XRD). The central composite design (CCD) based response surface methodology (RSM) was applied to study the influence of individual process variables such as temperature, catalyst load, methanol to oil molar ration and reaction time on biodiesel yield. Results: The obtained optimized conditions are as follows: temperature (165 ˚C), catalyst loading (1.625 wt%), methanol to oil molar ratio (15:1) and reaction time (143 min) with a maximum biodiesel yield of 95 %. The Gas chromatographymass spectrometry (GC-MS) analysis of biodiesel produced from waste cooking oil was showed that it has a mixture of both monounsaturated and saturated methyl esters. Conclusion: Thus the waste wood biomass derived heterogeneous catalyst for the transesterification process of waste cooking oil can be applied for sustainable biodiesel production by adding an additional value for the waste materials and also eliminating the disposable problem of waste oils.

Cerium oxide-based nanostructures as efficient catalysts for transesterification of methylacetate with n-butanol

CeO 2 -based nano materials have earned a great amount of interest in the field of catalysis because of excellent thermal stability and oxygen storage capacity. Cerium based mixed oxides prepared by coprecipitation method is used as heterogeneous catalysts in order to develop an effective catalyst with high activity and durability for the transesterification of methylacetate to butylacetate. Among the doped cerium oxide catalysts, vanadium doped ones showed maximum conversion with butylacetate selectivity around 76.0%. Reusability studies indicate that conversion percentage decreases on repeated uses whereas product selectivity remains more or less the same after each reuse. The decrease in catalytic activity was attributed to pore blocking of the active site as indicated by surface area and pore volume measurements.

Development of CaO supported on modified geopolymer catalyst for transesterification of soybean oil to biodiesel

Heterogeneous base catalysts, CaO supported on modified geopolymer (Geo), were developed and characterized as low-cost catalyst for biodiesel production from the transesterification of soybean oil. Geo was modified and synthesized by facile method, meta-kaolin and fumed silica were employed as sources of silica, alumina and, foaming agent (Al metal). The modified Geo was then compared to the conventional Geo without foaming agent (unfoamed-Geo). The catalysts, CaO with various loadings supported on Geo, were prepared by applying microwave radiation and subsequent calcination in air at 600 °C. The addition of Al metal during the synthesis of a geopolymer resulted in larger pore size. The results from CO2-TPD and XPS suggested that the calcium species dispersed with strong interactions in the aluminosilicate network of the geopolymer structure leading to strong basicity of the catalysts. The reactivity results showed that the fatty acid methyl ester (FAME) yield of 30%CaO/Geo was 93.12 ± 0.48%, larger amount than that of 30%CaO/unfoamed-Geo (70.87 ± 0.22%). Moreover, 30%CaO/Geo could be reused for at least 3 runs, suggesting a promising catalyst for cost-effective biodiesel production.

A Review on the Efficient Catalysts for Algae Transesterification to Biodiesel

The depletion of fossil fuel resources and increasing environmental pollution led to a trend for using alternative, clean, green, and sustainable fuel and energy resources. To attain this aim, using biomass as an alternative resource for diesel production has been a hotspot among researchers. Biodiesel has several advantages, such as being lower toxic and more renewable, and eco-friendlier than diesel from fossil fuel resources. Several edible and non-edible bio-sources were used for the production of biodiesel from the transesterification process. Algal oil as a non-edible source is considered an abundant, low cost and green substrate for biodiesel production. Various factors such as reaction conditions and the type of catalyst affect the biodiesel production process. Different catalytic systems such as basic and acidic homogeneous and heterogeneous catalysts and biocatalysts were introduced for the process in the literature, and each proposed catalyst has its own advantages and disadvantages. For instance, in spite of the lower cost and better mass transfer of base and acid homogeneous catalysts, reaction system corrosion, non-reusability, and soap formation are serious challenges of these catalysts at an industrial scale. On the other hand, acid and base heterogenous catalysts overcame the issues of corrosion and recovery, but some matters such as mass transfer limitation, high cost, and weak performance in catalyzing both esterification of FFAs and transesterification of lipids must be taken into account. In addition, bio-catalysis as a high-cost process led to a purer product formation with less side reaction. Therefore, several significant factors should be considered for transesterification catalysts such as availability, cost, reusability, stability, mass transfer, and the possibility to manage both the transesterification of triglycerides and the esterification of FFAs, selecting a catalyst with predominant pros is viable. Here, a review of the biodiesel production from algal biomass focusing on the efficient catalyst of the process is presented.

Green and facile synthesis of glycerol carbonate from bio-glycerol assisted by lithium titanate: A robust and selective heterogeneous catalyst

BackgroundGlycerol carbonate, an essential value-added product obtained from biodiesel byproducts, has diverse utilizations in pharmaceuticals, food, cosmetics, and chemical industries. The high price of glycerol carbonate constrains its remarkable applications; thus, research society has effectively focused on the synthesis of such compounds. MethodsA highly efficient heterogeneous catalyst Li/TiO2 was synthesized via the wetness impregnation method and applied for transesterification of glycerol with DMC to afford glycerol carbonate. The designed catalyst was studied by performing various characterization techniques such as XRD, TGA-DTA, XPS, FT-IR, FESEMEDAX, HR-TEM and ICP-MS analysis to obtain its physicochemical properties. 1H and 13C NMR spectroscopic methods were performed to determine the conversion of glycerol-to-glycerol carbonate. Significant findingsThe reaction parameters were also optimized, and the best conversion was obtained at a 1:3 molar ratio of Glycerol and DMC, 90 °C reaction temperature, 2 h’ reaction time, 500 rpm agitation speed and at 5 weight % catalyst loading. The highest conversion obtained was 95.5%, with a selectivity of 95.9% towards glycerol carbonate. These studies shows Li/TiO2 as an efficient catalyst for transesterification of glycerol to glycerol carbonate. Reusability study established that 25 wt.% Li/TiO2 catalyst can be successfully run for successive five catalytic cycles with effective glycerol conversion.

Unmodified Silica Nanoparticles Enhance Mechanical Properties and Welding Ability of Epoxy Thermosets with Tunable Vitrimer Matrix.

Epoxy/silica thermosets with tunable matrix (vitrimers) were prepared by thermal curing of diglycidyl ether of bisphenol A (DGEBA) in the presence of a hardener—4-methylhexahydrophthalic anhydride (MHHPA), a transesterification catalyst—zinc acetylacetonate (ZAA), and 10–15 nm spherical silica nanoparticles. The properties of the resulting material were studied by tensile testing, thermomechanical and dynamic mechanical analysis. It is shown that at room temperature the introduction of 5–10 wt% of silica nanoparticles in the vitrimer matrix strengthens the material leading to the increase of the elastic modulus by 44% and the tensile stress by 25%. Simultaneously, nanoparticles enhance the dimensional stability of the material since they reduce the coefficient of thermal expansion. At the same time, the transesterification catalyst provides the thermoset with the welding ability at heating, when the chain exchange reactions are accelerated. For the first time, it was shown that the silica nanoparticles strengthen welding joints in vitrimers, which is extremely important, since it allows to repeatedly use products made of thermosets and heal defects in them. Such materials hold great promise for use in durable protective coatings, adhesives, sealants and many other applications.

Magnetic iron oxide nanoparticles immobilized on microporous molecular sieves as efficient porous catalyst for photodegradation, transesterification and esterification reactions

Magnetic iron oxide nanoparticles immobilized on microporous molecular sieves as efficient porous catalyst for photodegradation, transesterification and esterification reactions

Synthesis of sulfonated mesoporous carbon from Calophyllum inophyllum oil cake as heterogeneous transesterification catalyst for biodiesel production: a process optimization study

ABSTRACT To address the concern of depleting resources and forge ahead toward sustainability, new renewable materials are being explored for multifarious applications. In this present study, sulfonated mesoporous carbon was synthesized using Calophyllum inophyllum oil cake by the process of carbonization, hydrothermal treatment, and KOH activation. Sulfonation of mesoporous carbon was characterized by BET, SEM, TEM, and FTIR. N2 gas adsorption-desorption studies were performed with the synthesized solid sulfonated catalyst and the total surface area, average pore volume, and diameter were estimated to be 618.3 m2 /g, 0.72 cm3 /g, and 5.27 nm respectively. The activated mesoporous carbon was then used in the catalysis of the transesterification reaction using Calophyllum inophyllum oil as a reactant. Finally, the biodiesel yield was found to be 93.2% with methanol: oil molar ratio of 1:14, the temperature of reaction 60°C, and 1.5 (wt %) of mesoporous catalyst.

Azolla pinnata methyl ester production and process optimization using a novel heterogeneous catalyst

This study concentrated on utilizing a novel heterogeneous dolomite catalyst in transesterification of Azolla pinnata algae oil with methanol to convert Azolla pinnata methyl ester (AME). The thermophysical properties of the catalyst were characterized by XRF, XRD, FTIR, and BET analysis. The optimized AME yield of 88.7% was obtained for the methanol to oil molar ratio (30:1), catalyst weight% (4 wt%), and operating temperature of (70 °C) through central composite design (CCD) in response surface methodology (RSM) technique. Five different proportions of Azolla pinnata methyl ester (AME) viz., 10%, 20%, 30%, 40% and 100% by volume were blended with 90%, 80%, 70%, 60% and 0% by volume of diesel. These AME test fuel blends were named AME10, AME20, AME30, AME40, and AME100. American Society for Testing and Materials (ASTM D6751) standards followed to testing the thermophysical properties of prepared biodiesel. AME fuel blends were tested in the single-cylinder variable compression ratio (VCR) engine with varied compression ratios (CR) of 16:1, 17:1, and 18:1 for different loadings at a constant speed of 1500 rpm. The performance, in-cylinder combustion, and exhaust emission results were concluded among five different diesel-AME blends at varied compression ratios. The obtained results for AME blends were compared with the diesel fuel under the same working conditions. At peak load condition, AME30 test fuel with CR18:1 gives a reduction of CO (14.0%), HC (12.06%) and smoke opacity (5.88%) and slight increment in NOx (2.46%) emissions as well as reduced BTE (10.20%) and increased BSEC (17.33%) were obtained related to diesel fuel. Better diffusion phase combustion was recorded for AME blends due to their higher cetane value than neat diesel.

Comparative study of unmodified Iyi-Nsukka and unmodified Ukpo kaolinite clays as catalysts for transesterification of gmelina seed oil

Comparative study of unmodified Iyi-Nsukka and unmodified Ukpo kaolinite clays as catalysts for transesterification of gmelina seed oil

Improvement of potassium species dispersed on hierarchical zeolite NaY by using combined methods between ultrasound and microwave-assisted impregnation as catalysts for transesterification of refined Jatropha seed oil

Refined Jatropha seed oil, non-edible vegetable oil is an interesting source for biodiesel production because it has low commercial value. Thus, this work aimed to develop a novel method, combined techniques between ultrasound and microwave-assisted impregnation ((UA-IP and MA-IP) for potassium (K) loaded on hierarchical NaY zeolite synthesized from rice husk silica as catalysts for transesterification of Jatropha seed oil. Hierarchical NaY zeolite was impregnated with potassium acetate in an acetic acid buffer solution with various contents (xK/NaY, where X = 6, 8, 10, and 12 wt%) by UA-IP and MA-IP. The best catalyst from the novel method was further compared to the control method, prepared by only UA-IP. Results from XRD and N2-sorption indicated the remaining NaY structure in all samples after calcination. The total surface area determined by BET method decreased with the K loading but basicity increased with K loading suggested by CO2 -TPD. The active species was mainly K2CO3 confirmed by FTIR. When tested in transesterification at a temperature of 60 °C and 3 h with methanol: oil molar ratio of 16:1, the biodiesel yield improved with the K loading and the highest biodiesel yield of 97 ± 1.4% was obtained by 12K/NaY. The 12K/NaY gave a higher yield than 12K/NaY-control (97 ± 1.4% vs 90.7 ± 1.1%), providing the high reusability of five cycles with the biodiesel yield of 88.2 ± 1.3%.

Emission Characteristics of Third Grade Oil Converted Sesame Biodiesel

The demand and usage of fossil fuels has been increasing drastically, leading us to search for alternate fuels. The sesame seed is selected as an alternate fuel source, as a focus for this research paper. The sesame biodiesel is a type of fuel that has been obtained through the transesterification process from sesame oil using base catalyst transesterification. The sesame biodiesel was blended with four different ratios B10, B20, B30 and B40, among which B20 resulted with better stability, tested in the Kirloskar 240PE VCR engine at a compression ratio of 17.5:1 and 18:1 in various loads. The FTIR test was performed on sesame biodiesel, and it has shown that ester content was present in the test sample confirming its usage as the biodiesel. The fuel properties were found for all the three: sesame oil, sesame biodiesel(B20), diesel and it was found to be within the permissible limit. The result reveals that B20 is the best possible blend that has given good results in emission characteristics. The smoke emission testing was done on AVL emission analyser. It has been noted and observed that there is good reduction in CO, CO2, and HC than with standard diesel rate at all loads. An increased amount of NOx is observed as the load increases. It was also noted among the two compression ratios, 18:1 depicted best results considering the emission levels. It is observed that the sesame biodiesel can be used in IC diesel engines with a better outcome than the standard diesel rate. Hence, the work established the need for conversion of sesame seed oil to biodiesel and also suggests that sesame oil could be effectively used as feedstock for biodiesel production.

Effect of alumina support on cow bone based catalyst in one-step transesterification of neem seed oil

Alumina supported heterogenous base catalyst (CaO/alumina) was developed from cow bone via wet impregnation method and used with Ferric sulphate for one step transesterification of neem seed oil. Effect of alumina support on cow bone ash was studied for transesterification process and was compared with cow bone ash without alumina support. Transesterification of the neem seed oil was done at 120 minutes for 3 %w/w, 4 %w/w, 5 %w/w and 6 %w/w catalyst loading at 60 0 C temperature and 15:1 methanol to oil ratio. Optimum conversion of biodiesel was at 2 hours reaction time and 5 wt % catalyst loading, 4:1 Ferric sulphate to cow bone ash ratio, 60 0 C temperature and 15:1 methanol to oil ratio for cow bone ash supported with alumina. The synthesized catalyst was characterised using X-Ray Fluorescence (XRF), Brunauer–Emmett–Teller ( BET ) and scanning electron microscopy (SEM) analysis. The transesterified oil was analysed using Fourier-transform infrared spectroscopy (FTIR) and Gas chromatography–mass spectrometry (GCMS) analysis. GCMS analysis gave a conversion of 96.53% for cow bone ash/Al 2 O 3 and 76.33% for cow bone without support. The oil was also characterised for physicochemical properties which meets ASTM standard. Result showed that synthesized catalyst using alumina support enhanced production of high yield biodiesel in 2 hours reaction time.

Establishing rational conditions for obtaining potassium glycerate

This paper reports a study into the dependence of efficient glycerate potassium production involving glycerin and potassium hydroxide solution on the process conditions. The concentration of potassium glycerate in the resulting product has been used as a parameter of the efficient glycerate potassium production process. Glycerates of metals are applied to produce articles in the construction industry, electronics, medicine; they are employed as transesterification catalysts to obtain special fats for various purposes, as well as biodiesel fuel. In order to derive potassium glycerate, heating was applied while agitating a mixture of glycerin and potassium hydroxide. The analysis of potassium hydroxide was performed, in which the basic substance mass fraction was 85.5 %, the mass fraction of carbonate potassium – 0.9 %. The p.a.-grade glycerin was applied in this work, whose basic substance mass fraction was 99.5 %. The effect of the heating temperature of the reaction mixture on the concentration of potassium glycerate in the product has been determined. It has been shown that the rational heating temperature is 145 °C. The dependence of potassium glycerate concentration in the resulting product on the following conditions of the process has been established: a change in the molar concentration of glycerin and a reaction mixture heating duration. Such rational conditions for obtaining potassium glycerate have been defined as a molar concentration of glycerin of 60 % and a heating duration of 4 hours. The experimentally established concentration of potassium glycerate in the product under these conditions was 75.77 %. For potassium glycerate, the melting point (69 °C) and the mass fraction of moisture (0.8 %) have been determined. The results of experimental studies would make it possible to obtain potassium glycerate directly at enterprises where the glycerates of metals are used, from available raw materials, under rational conditions. The defined conditions for obtaining potassium glycerate could make it possible to efficiently utilize material and energy resources.

Highly active and durable Ca-based solid base catalyst for biodiesel production

Calcium-based (Ca-based) oxides are promising candidates to replace sodium or potassium hydroxide as base catalysts in transesterification for biodiesel production, owe to their high activity and recyclability. However, their readily leaching in the reaction process is the main reason for its low reusability. This problem has long been the bottleneck of heterogeneous catalytic transesterification for biodiesel production. To solve this problem, we employed a solid-state synthesis approach to fabricate the Ca-based solid base catalyst, which showed extraordinarily high activity and stability for biodiesel synthesis. The catalyst, named NCS, could achieve up to 98.0% biodiesel (fatty acid methyl esters, FAMEs) yield in 1 h at 90 °C with 5 wt% of catalyst loading. The catalyst can be reused 26 times with a biodiesel yield of at least 90.0%. With thorough characterization, we found that the extraordinary performance of the catalyst owes to the strong basic sites and its anti-carbonation ability. The strong basic sites, formed by the coordination between O, Na, Si, and Ca, can also moderate the leaching of Ca-related basic sites into the reaction medium. Performance reduction of NCS could be attributed to the shift of strong basic sites to weaker ones without significant loss of total basic sites. Above all, we believe that the NCS catalyst is a promising catalyst for large-scale biodiesel production.

Physical characteristics and utilization of ZSM-5 prepared from rice husk silica and aluminum hydroxide as catalyst for transesterification of Ricinus communis oil

Natural and synthetic zeolites are well-known materials sharing a wide range of applications, such as adsorbents, ion exchange, and catalysts. However, synthetic zeolites are more widely used, due to several limitations of natural zeolites, such as the presence of impurities and diverse compositions. In this study, rice husk silica (97.86% purity) and aluminum hydroxide were utilized for the preparation of ZSM-5, to study the effect of crystallization time on the physical characteristics and catalytic activity in the transesterification of Ricinus communis oil. The raw materials, with molar ratio of SiO2:0.025Al2O3:0.165Na2O:25H2O, were subjected to crystallization at 180 °C for 48, 72, 96, and 120 h, completed by 6 h calcination at 600 °C. The formation of ZSM-5 was demonstrated by FTIR, XRD, and SEM techniques, confirmed that the formation of ZSM-5 had taken place at 48 h crystallization, with no significant change with prolonged time. The PSA indicates the existence of two clusters of particles, and the BET confirmed the existence of the zeolites as porous materials, with the sample prepared with crystallization time of 96 h had the largest surface area and smallest pore diameter. This particular sample exhibited the highest activity, resulting in 96% conversion of Ricinus communis oil.

Supercritical transesterification route for biodiesel production: Effect of parameters on yield and future perspectives

AbstractCatalyst‐free biodiesel production through supercritical transesterification is faster with the high conversion and a more environment‐friendly route than conventional catalyst transesterification. Improving and exploring the new possibilities in this alternative biodiesel production method by including newly available technology will lead us to a more sustainable future. In this paper, supercritical transesterification of biodiesel production has been reviewed in detail. The different parameters of this method, such as temperature, pressure, molar ratio, alcohol types, and residence time which affect the yielding and quality of fuel, have been reviewed. Besides, recycling the energy and suitable feedstock for this method has also been explored to reduce the intensive energy demand and operating cost. Furthermore, light has also thrown on co‐solvents effect on this method to reduce the extreme reaction conditions required. At last, the review concludes future recommendations in supercritical transesterification along with the challenges in energy integration and recycling.

Stabilizing Triglyceride in Methanol Emulsions via a Magnetic Pickering Interfacial Catalyst for Efficient Transesterification under Static Conditions.

Pickering emulsion systems provide potential platforms for simultaneously intensifying and catalyzing transesterification between triglyceride and methanol under static conditions. However, realizing static transesterification with high biodiesel yield is still challenging due to low emulsion stability at the reaction temperature. Here, a series of magnetically recyclable Pickering interfacial catalysts (PICs) with similar surface affinities but different densities were constructed as stabilizers of a soybean oil/methanol emulsion. The variations in the emulsion volume fraction and droplet size were comparatively studied and analyzed from the viewpoint of droplet settling and catalyst particle shedding. It is found that, except for surface affinity, PIC density also plays a pivotal role in emulsion stability owing to the non-negligible effect of gravity on catalyst adsorption in triglyceride/methanol emulsion (especially at elevated temperature). By reducing the density, finely improving the lipophilicity, and optimizing the addition amount of PIC, the obtained soybean oil/methanol emulsion can remain stable for at least 12 h at 60 °C, enabling static transesterification with a high biodiesel yield of 95.6%. Moreover, the best performing PIC can be reused for at least 7 cycles. This efficient static transesterification system offers a green strategy for biodiesel production.

Layered double hydroxide uniformly coated on mesoporous silica with tunable morphorlogies for catalytic transesterification of glycerol with dimethyl carbonate

Layered double hydroxides (LDH) is an attractive solid base catalyst for transesterification of glycerol with dimethyl carbonate. A major challenge in enhancing the catalytic performance of LDH for this process is to overcome the internal diffusion limitations and increase the availability of basic sites. Herein we present ultrasonic and hydrothermal post-synthesis strategies in uniformly coating of LDH on mesochannels of mesoporous silica. The effects of precursors, preparation methods and morphologies on preparing LDH/SBA-15 nano-composites were investigated. Rice-shaped LDH/SBA-15 nano-composite catalysts exhibited better performance with a 78% glycerol conversion and 90% selectivity of glycerol carbonate than the catalysts with morphologies of short-rods, and long-rods. The results revealed that hierarchical nanostairs at the edge and well-ordered mesochannels stacked along the long axis direction reduced internal diffusion path lengths and increased availability of basic sites. This approach in morphology controlling synthesis of LDH based nano-composite catalysts shed light on the uniformly coating of other diatomic and triatomic metal LDH within mesochannels of mesoporous silica to fabricate novel nano-composite catalysts.