Conversion Of Soybean Oil Research Articles

Hydrocracking of soybean oil using zeolite–alumina composite supported NiMo catalysts

Composite supports were prepared by kneading various zeolites (USY (SiO2/Al2O3=14), HY (5.5), Beta (37), ZSM-5 (90) and ZSM-5 (1770)) (25wt%), commercial alumina (60wt%) and alumina-sol (15wt% as Al2O3) with water. Supported NiMo catalysts were successfully prepared by the conventional impregnation method with the composites. The reactant soybean oil was hydrocracked with these catalysts. Conversion of soybean oil reached almost 100% for every catalyst even at 325°C the lowest temperature used while the products largely depended on the kinds of zeolite. NiMo/Al2O3 and NiMo/25USY(14)60A mainly produced diesel fractions and, specifically the latter catalyst improved iso-/n-ratio contributing low-temperature stability of diesel oil. The cetane number of diesel fractions of them reached 80. For the case of NiMo/25Beta(37)60A produced about 70% of gasoline fraction and RON value reached more than 80. As a result, it was found that gasoline and diesel fractions could be prepared selectively by choosing the proper kind of zeolite in the zeolite–alumina composite supported NiMo catalysts.

High quality diesel-range alkanes production via a single-step hydrotreatment of vegetable oil over Ni/zeolite catalyst

A single-step hydrotreatment of vegetable oil to produce high quality diesel-ranged alkanes over Ni/zeolite catalyst is devised. The Ni/zeolite catalysts prepared by incipient wetness impregnation method using SAPO-11, ZSM-5, ZSM-22, ZSM-23 and Beta zeolites as supports are evaluated in this single-step hydrotreatment process. The effects of the support and the metal loading amount are studied from the catalytic performance and characterization results obtained by techniques such as XRD, Physisorption, NH3-TPD and Pyridine-IR. Over the 8wt%Ni/SAPO-11 catalyst, 100% conversion of soybean oil is obtained at 370°C, 4MPa and 1h−1, with an organic liquid yield of 74.8% which is nearly 90% of the maximum theoretical liquid yield. In the organic products, the alkane selectivity is 100%, and more than 85% isomerization selectivity is achieved. In order to learn the detailed scheme of the single-step hydrotreatment process, the intermediates have been analyzed from which reaction pathways are proposed and discussed.

Treatment of clay with KF: New solid catalyst for biodiesel production

A novel solid catalyst with basic properties was developed from untreated smectite chemically modified by treatment with potassium fluoride, resulting in a material with excellent stability and high catalytic activity in the conversion of soybean oil into biodiesel in the presence of methyl alcohol. The percentage of conversion into methyl esters of 99.7% was obtained under conditions of 1h of reaction time at 338K, 15wt.% catalyst and molar ratio of methanol/oil of 6:1. A concomitant study was made to evaluate the effect of the mineralogical composition of the untreated clay on the properties of the catalysts and their performance in the transesterification reaction.

Novozym 435-catalyzed synthesis of fatty acid ethyl esters from soybean oil for biodiesel production

This paper deals with transesterification of soybean oil with ethanol in the presence of Novozym 435 (lipase from Candida antarctica) catalyst. 1H NMR was employed to monitor the conversion of soybean oil to fatty acid ethyl esters in a solvent-free medium. Reaction conditions such as enzyme/substrate ratio, temperature and alcohol to oil molar ratio were studied and the highest yields were found at 5 g of enzyme per 100 g of oil, 37 °C, and 3:1 respectively. Stepwise addition of ethanol was also performed, and compared with that of methanol, in order to assess the reduction of inhibition that this method causes on the enzymatic activity.

Effect of calcination temperature and MgO crystallite size on MgO/TiO2 catalyst system for soybean oil transesterification

The effect of calcination temperature and MgO crystallite sizes on the structure and catalytic performance of TiO2 supported nano-MgO catalyst for the transesterification of soybean oil has been studied. The catalyst has been prepared by deposition–precipitation method, characterised by XRD, TEM, XRF, BET and FTIR and tested in a batch autoclave at 225 °C. The soybean oil conversion after 15 min of the transesterification reaction increased when the calcination temperature was increased from 500 to 600 °C and decreased with further increase in calcination temperature. Some glycerolysis activity was also detected on catalysts calcined at 600 and 700 °C after 45 min of reaction. The soybean oil conversion during the transesterification reaction increased with the decrease in MgO crystallite size for the first 30 min.

USE OF CERAMIC MATERIAL (CEMENT CLINKER) FOR THE PRODUCTION OF BIODIESEL

Biodiesel is a renewable liquid fuel made from natural, renewable biological sources such as edible and non edible oils. Over the last years, biodiesel has gained more market due to its benefits and because it appears as the natural substitute for diesel. Reasons for growing interest in biodiesel include its potential for reducing noxious emissions, potential contributions to rural economic development, as an additional demand center for agricultural commodities, and as a way to reduce reliance on foreign oil. Biodiesel was prepared from soybean oil by transesterification with methanol in the presence of cement clinker. Cement clinker was examined as a catalyst for a conversion of soybean oil to fatty acid methyl esters (FAMEs). It can be a promising heterogeneous catalyst for the production of biodiesel fuels from soybean oil because of high activity in the conversion and no leaching in the transesterification reaction. The reaction conditions were optimized. A study for optimizing the reaction parameters such as the reaction temperature, and reaction time, was carried out. The catalyst cement clinker composition was characterized by XRF. The results demonstrate that the cement clinker shows high catalytic performance & it was found that the yield of biodiesel can reach as high as 84.52% after 1 h reaction at 65°C, with a 6:1 molar ratio of methanol to oil, 21 wt% KOH/cement clinker as catalyst.

Biodiesel Synthesis Evaluated by Using Real-Time ATR-FTIR

Real-time attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) was used as an analytical method capable of providing quantitative data regarding the yield of biodiesel synthesis. 1H NMR was used as a reference technique to check the consistency of the data obtained by ATR-FTIR. The evaluation of the conversion of soybean oil into biodiesel was performed by measuring the consumption of methanol during the reaction.

Glymes as new solvents for lipase activation and biodiesel preparation

Glymes (i.e. glycol diethers) were explored as alternative benign solvents for enzymatic reactions, specifically the lipase-catalyzed transesterification. Long-chain glymes were found highly compatible with immobilized Candida antarctica lipase B (iCALB), leading to higher enzyme activities and stabilities than t-butanol and ionic liquids (e.g. the rate of transesterification in diethylene glycol dibutyl ether (G2-Bu) was 77% higher than that in t-butanol). Furthermore, soybean oil was found fully miscible with glymes, which enabled a homogeneous reaction mixture for the enzymatic preparation of biodiesel. In the presence of glymes, CALB showed a very high tolerance to high methanol concentrations (up to 60–70% v/v), and nearly stoichiometric triglyceride conversions could be obtained under mild reaction conditions. A laboratory scale-up achieved a high conversion of soybean oil (95.5%). This study suggests that glymes can be environmentally friendly and inexpensive solvents for lipase-catalyzed reactions, such as the enzymatic preparation of biodiesel.

Production of biodiesel from soybean oil on CaO/Al2O3 solid base catalysts

Transesterification of soybean oil was carried out over calcium oxide supported on Al2O3 as solid base catalysts. Solid base catalysts were synthesized by wet impregnation of CaO on acidic, basic and neutral Al2O3. Solid basic catalysts investigated in this study were characterized by BET surface area, XRD, FTIR, CO2-TPD and TG/DTA techniques. Formation of fatty acid methyl esters (FAME) in this study was influenced by the nature of the catalyst prepared on different Al2O3 supports. CaO supported on neutral-Al2O3 exhibited higher FAME yield and the activation energy was determined to be 30.7kJ/mol. The formation of the calcium diglyceroxide (CDG), on the surface of CaO supported on neutral Al2O3 was established by 13C NMR spectroscopy. The catalytic system (with CaO+CDG) on neutral Al2O3 showed higher activity in the transesterification of soybean oil. Among the catalysts studied the conversion of soybean oil to FAME formation was as follows: CaO/neutral-Al2O3>CaO/basic-Al2O3>CaO/acidic-Al2O3. The presence of CDG on neutral Al2O3 probably contributes to the higher activity. To our knowledge, this is the first report on identifying the formation of CDG on neutral Al2O3 during the production of biodiesel.

Aminopropylsilica as an environmentally friendly and reusable catalyst for biodiesel production from soybean oil

In this study, 3-aminopropylsilica was prepared by a reaction of silica gel with 3-aminopropyl(trimethoxy)silane, and used as a heterogeneous catalyst for soybean oil transesterification with methanol. This 3-aminopropylsilica catalyst was characterized by Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), thermo gravimetric and differential thermal analysis (TG–DTA) and nitrogen adsorption–desorption technique. The transesterification conditions, such as the molar ratio of methanol to oil, reaction temperature, reaction time, and catalyst dosage were investigated. It was shown that the conversion of soybean oil to methyl esters could reach 94.5% when the reaction was performed with a molar ratio of methanol to soybean oil of 30:1, a catalyst amount of 8wt.%, at a reaction temperature of 423K. The free fatty acid and water present in the feedstocks decreased the catalyst activity in the transesterification reaction. The heterogeneous catalyst could be recovered with a better reusability.

One‐Step Hydrotreatment of Vegetable Oil to Produce High Quality Diesel‐Range Alkanes

A one-step hydrotreatment of vegetable oil combining deoxygenation and isomerization to directly produce low cloud point, high quality diesel is devised. The Pt/zeolite bifunctional catalysts prepared by using SAPO-11 and ZSM-22 zeolites as supports are used in this process. Catalytic reactions are conducted in a fixed-bed reactor under a hydrogen atmosphere. Over the bifunctional catalyst, 100 % conversion of soybean oil is obtained at 357 °C, 4 MPa, and 1 h(-1), and 80 % organic liquid yield is achieved, which is close to the maximum theoretical liquid yield. In the organic products, the alkanes selectivity is 100 % with an i-alkanes selectivity above 63 %. NH(3)-temperature programmed desorption (TPD), pyridine IR spectroscopy, and other characterization techniques are used to study the effect of the support acidity on the reaction pathway. Over the Pt/zeolite bifunctional catalyst with less strong Lewis acid sites, the reaction proceeds via the decarboxylation plus decarbonylation pathway. This one-step method provides a new strategy to produce low cloud point, high quality diesel from biomass feedstock in a more economic and attractive way.

Monitoring the conversion of soybean oil to methyl or ethyl esters using the refractive index with correlation gas chromatography

A simple method (refractive index) was applied to monitor the progress and the end point of the transesterification reaction of soybean oil to biodiesel (methyl or ethyl esters). Additionally, the same method may be used to determine the methyl or ethyl ester content during the transesterification reaction progress. To do so, blends of biodiesel and soybean oil were prepared at different wt.% to obtain a simple linear correlation with the refractive index and a correlation coefficient (R2) of 0.9997 and 0.9996 for the FAMEs and FAEEs, respectively. The transesterification process of soybean oil with methanol and ethanol was performed to determine how the refractive index properties change due to the ratio of conversion. It was concluded that in the reaction kinetics of the methanolysis reaction, the efficiency was over 90% in 8h. Compared with existing chromatographic techniques, the refractive index method for monitoring the transesterification of vegetable oils presented good results. Additionally, the method was rapid, inexpensive and especially suitable for process control applications.

Immobilized lipase on magnetic chitosan microspheres for transesterification of soybean oil

Biodiesel fuel, produced by transesterification of vegetable oils or animal fats with methanol, is a promising alternative diesel fuel due to the limited resources of fossil fuels and the environmental concerns. An environmentally benign process for the transesterification reaction using immobilized lipase has attracted considerable attention for biodiesel production. In the work, magnetic chitosan microspheres were prepared by the chemical co-precipitation approach using glutaraldehyde as cross-linking reagent for lipase immobilization. The immobilization of lipase onto the magnetic particles was confirmed by magnetic measurements, transmission electron microscopy (TEM) and Fourier transform infrared (FT-IR) spectra. Using the immobilized lipase, the conversion of soybean oil to fatty acid methyl esters reached 87% under the optimized conditions of methanol/oil amount-of-substance ratio 4:1 with the three-step addition of methanol, reaction temperature 35 °C, and reaction duration 30 h. Moreover, the immobilized lipase could be used for four times without significant decrease of the activity.

Transesterificarion of soybean oil using ethanol and mesoporous silica catalyst

Mesoporous silica catalyst was evaluated in the ethanolysis of soybean oil. Ethanol can be environmentally advantageous over methanol (more frequently used as reagent in biodiesel production) because it can be obtained from renewable sources whilst methanol is usually derived from mineral sources. A silica molecular sieve containing lanthanum oxide as active phase (La 50SBA-15) was obtained by isomorphous substitution into the SBA-15 network using Pluronic (P123) dissolved in aqueous HCl solution with tetraethyl orthosilicate and a given amount of hydrated lanthanum chloride (Si:La = 50) at 333 K. The reaction was performed using the molar ratio ethanol:soybean oil of 20:1 at inert atmosphere (N 2) at 343 K with 1wt% of catalyst mass relative to total oil mass added to the reaction mixture. The reaction was evaluated for ethyl ester conversion after 6 h. The ethyl esters content was measured using low frequency 1H NMR spectroscopy (60 MHz). The La 50SBA-15 heterogeneous catalyst presented conversion of soybean oil in ethyl esters as high as 80% after reaction time of 6 h., comparing well with previous reports for methanolysis of soybean oil. Moreover, lixiviation of the active phase was not observed, thus excluding the contribution of the homogeneous catalysis to the studied transesterification process.

Pseudomonas cepacia lipase immobilized onto the electrospun PAN nanofibrous membranes for biodiesel production from soybean oil

Abstract Lipase from Pseudomonas cepacia has good transesterification activity and can be employed for biodiesel production. For recycled uses, polyacrylonitrile nanofibrous membrane was fabricated by electrospinning method and activated by amidination reaction for immobilizing P. cepacia lipase. Fourier transform infrared spectroscopy (FTIR) spectra confirmed that the lipases were covalently attached to the nanofibers. After enzyme immobilization, the immobilized P. cepacia lipase was used as the catalyst for transesterification reaction to convert the soybean oil to biodiesel by adding methanol as the reactant. The effects of methanol concentration, methanol-to-water ratio, reaction temperature, fatty acid content and the reusability were investigated by using the immobilized P. cepacia lipase. Under the optimal reaction conditions, the biodiesel conversion of soybean oil achieved 90% after reacting 24 h. In examining the reusability, the immobilized P. cepacia lipase still retained 91% of its initial conversion capability after 10 times reused.

Application of N-methylimidizolium functionalized anion exchange resin containing NaOH for production of biodiesel

Biodiesel produced by vegetable oil transesterification is a potential alternative fuel to diesel regarding the limited resources of fossil fuel and its environmental concerns. In this paper, N-methylimidazole functionalized anion exchange resin (R +–OH −) containing NaOH was synthesized through two-step method and applied for transesterification of soybean oil. R +–OH − was found to show some polarity due to the functional groups of N-methylimidazole and hydroxyl, and NaOH could be absorbed in R +–OH − to form R +OH − (Na). Both soybean oil and methanol will be compatible to the partly-polar R +OH − (Na), and the reaction will be enhanced by the co-catalysis of R +–OH − with NaOH. The properties of R +–OH − (Na) were studied, such as ion exchange capacity, stability and microstructure. The influences of the molar ratio of methanol to soybean oil, stirring speed and the amount of R +–OH − (Na) were investigated. The conversion of soybean oil was up to 97.25% at the optimal condition: molar ratio of methanol to soybean oil 12:1, the amount of catalyst 2.5%, reaction temperature 50 °C, stirring speed 570 rpm and reaction time 10 h. The co-catalysis of R +–OH − with NaOH improved the yield of biodiesel greatly, and R +–OH − (Na) could be reused after regeneration.

Immobilization of calcium oxide onto chitosan beads as a heterogeneous catalyst for biodiesel production

AbstractA biopolymer, chitosan, was used as a novel substrate for the immobilization of calcium oxide (CaO). CaO immobilized onto chitosan beads was employed as a heterogeneous catalyst to produce biodiesel catalytically, through transesterification of soybean oil with methanol. To obtain a stable immobilized catalyst, the chitosan beads with immobilized CaO were cross‐linked with glutaraldehyde. Two crosslinking parameters, crosslinking time and glutaraldehyde concentration, were studied to reveal the optimal immobilization conditions, which were 30 min and 0.22 mol L−1, respectively. Under those conditions, an immobilized catalyst with a very low degree of CaO leaching could be obtained. The immobilized CaO catalyst obtained was investigated by being used to catalyze the transesterification of soybean oil with methanol. The transesterification rate, which was affected by catalyst loading, molar ratio of methanol to oil and temperature, was investigated by using response surface methodology. A maximum reaction rate of 0.6 h−1 was obtained at 60 °C, methanol to oil molar ratio of 13.4 and catalyst loading of 13.78 wt%. Under these reaction conditions, the equilibrium conversion of soybean oil was 97% after 3 h of reaction time. In addition, the immobilized catalyst could be reused at least five times. This study developed an easy and energy‐efficient process for preparing a chitosan‐based immobilized CaO catalyst, which is promising for potential applications including biodiesel production. Copyright © 2011 Society of Chemical Industry

Continuous-flow biodiesel production using slit-channel reactors

Slit-channel reactors are reactors whose active surface areas are orders of magnitude higher than those of micro-reactors but have low fabrication costs relative to micro-reactors. We successfully produced biodiesel with different degrees of conversion using homogeneous catalyst in the slit-channel reactor. The reactor performance shows that percent conversion of soybean oil to biodiesel increases with channel depth, as expected, due to more efficient mixing. Shallow slit-channels require short average residence times for complete product conversion. Present results show that the slit-channel reactor provides an improved performance over traditional batch reactors using homogeneous sodium alkoxide catalyst. It is aimed to couple the reactors with solid catalysts in converting soybean oil to biodiesel and implementation method is suggested. The cost advantages resulting from the ease of fabrication of slit-channel reactors over micro-reactors and how these factors relate to the oil conversion efficiency to biodiesel are briefly noted and discussed.

Transesterification of soybean oil on guanidine base-functionalized SBA-15 catalysts

SBA-15 functionalization with the guanidine base 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) was used to prepare TBD-grafted catalysts for the soybean oil transesterification reaction. The structural and textural features of both the support and the catalysts were investigated by X-ray diffraction, transmission electron microscopy, and nitrogen physisorption. CHN analysis and FTIR characterization were also carried out on the catalysts before and after reaction. Potentiometric titration was also used to confirm CHN analysis data for the fresh catalysts. Mild conditions (atmospheric pressure and 343K) were chosen for catalytic testing in a batch reactor. The influence of the base content and the reaction time on the methyl esters yield was investigated. All the catalysts were found active for the soybean oil conversion. Comparison with the catalytic behaviour of a commercial TBD-grafted polymer showed a superior performance of the functionalized SBA-15 catalysts. The higher the functionalization extent, the higher the activity, just a few hours being required for a 100mol% methyl esters yield. Over such a short reaction time leaching was observed to occur only to an extremely low extent, which makes possible to reuse the catalysts after a regeneration step consisting in a simple NaOH treatment of the recovered samples. During such treatment the catalyst base sites – poisoned (through protonation) by the free fatty acids – are freed, and their activity is restored.

Biodiesel production by methanolysis of soybean oil using calcium supported on mesoporous silica catalyst

The transesterification of soybean oil with a CaO/mesoporous silica catalyst was achieved. The effects of CaO loading levels in the mesoporous silica catalyst, the amount of catalyst to substrate level and the reaction temperature and time on the conversion of soybean oil were investigated. Increasing the temperature and reaction time raised the total conversion of soybean oil attained. The optimized condition, found to be 15 wt.% of Ca loading on the mesoporous silica catalyst, a 5% (w/w) catalyst to oil level and a reaction temperature of 60 °C for 8 h, provided the highest yield of 95.2%. The fuel properties of the biodiesel obtained under these optimized conditions were acceptable under the biodiesel standards of Thailand.