Castor Oil Fatty Acid Research Articles

Formulation of a stable diesel microemulsion using eco-friendly ionic liquids and investigation of particle size and fuel properties as an alternative fuel

Ecofriendly ionic liquids (ILs) were synthesized through amidation of ricinoleic acid, the main fatty acid in castor oil, followed by a quaternization reaction to solubilize ethanol in IL/diesel blends at different ratios. As a result, stable and highly renewable, low viscous microemulsion biofuels with high oxygen content were prepared. The prepared fuel samples combine the advantages of green ionic liquids and microemulsion properties. The chemical structures of ILs were confirmed with the aid of NMR and FTIR spectroscopy. DLS analysis revealed that the ethanol particles ranged in size from 8 to 18.1 nm in all samples. As ILs ratios decrease in microemulsion from 37 to 69%, the ethanol particle sizes increase from 10 to 25%. Ethanol shows good solubilization in diesel and IL-1 is more effective than IL-2 in ethanol solubilization at low percentages of ethanol due to more oxygen atoms besides three hydroxyl groups. The ternary phase diagram indicated that the microemulsion area in the case of using IL-1 is larger than that of IL-2. The fuel properties of the prepared microemulsions are nearly close to those of neat diesel and fall within the permitted range of ASTM D975. The viscosity and density values at low ratios of ILs are found to be very close to the values of the neat diesel at different temperatures. The prepared samples show a slight decrease in cetane number and heating value compared to diesel. However, they have improved flash points, cloud points, sulfur content, and acid value. The particle sizes were checked every week and the prepared samples showed high stability with the aid of the synthesized ILs. Moreover, the prepared microemulsions stayed in a transparent appearance for more than a year and no phase separation was observed.

Reaction kinetics involved in esterification between the fatty acids in castor oil and furfuryl alcohol

Kinetics of esterification reaction between furfuryl alcohol (FA) and castor oil fatty acid (COFA) using immobilized Candida antartica lipase B in a solvent free system is investigated in present study. The well-known ping-pong bi bi mechanism with two-substrate inhibition has been confirmed to correctly describe the governing reaction pathway. Subsequently, the rate equation was used to evaluate pertinent kinetic parameters. Parametric optimization study was also carried out with respect to temperature, molar ratio of reactants and enzyme loading to maximize the equilibrium yield of COFA ester. Furthermore, functional variations of the kinetic parameters, which include Michaelis-Menten constants and inhibition coefficients, were evaluated with respect to three process parameters. Corresponding inferences are of high utility, specifically, in cases where the global optimum is beyond the scope of the existing production facility in any industrial platform.

Development of a novel hyperbranched unsaturated polyester resin: Synthesis, characterization, and potential applications in car body putty

This work presents a comprehensive synthesis method for the development of a new hyperbranched unsaturated polyester resin (HUPR). The resin is synthesized by modifying dehydrated castor oil fatty acid (DCOFA) with methyl methacrylate (MMA) and styrene, dicyclopentadiene-maleate (DCPD-M), and trimethylol propane diallyl ether (TMPDE). The synthesis process involves the radical addition reaction of DCOFA with MMA and styrene, followed by the addition of DCPD-M and TMPDE to form a HUPR. The resulting resin exhibits enhanced properties, making it a promising candidate for car body putty in the polymer industry.

Thermo-Oxidative Stability and Tribological Properties of Biolubricants Obtained from Castor Oil Fatty Acids and Isoamyl Alcohol

In this study, the thermo-oxidative stability and tribological behavior of bio-based lubricant samples synthesized from castor oil using isoamyl alcohol were evaluated. Initially, the compositional and physicochemical properties of the obtained samples were assessed using the 1H NMR, FTIR and ASTM methods. Oxidative stability of the samples was evaluated using the Rancimat method at 110 °C under air flow. The final biolubricant sample (BL2), obtained after esterification, epoxidation and oxirane rings opening reactions, presented an oxidation stability time (OST) of 14.3 h. The thermal stability was also evaluated by thermogravimetry (TG) from the mass variations under inert and oxidative atmosphere. BL2 showed higher thermal stability compared to the other samples, demonstrating higher decomposition temperatures in both inert (339.04 °C) and oxidative (338.47 °C) atmospheres, for a mass loss of 50%. The tribological properties of the samples were evaluated using a four-ball tribometer configuration. The BL1 and BL2 samples exhibited lower friction coefficients than the mineral oil sample (MOS) by 21.5% and 43.1%, respectively. Regarding wear, the observed wear scar diameter (WSD) was also lower in BL1 and BL2 compared to MOS by 5.2% and 40.4%, respectively. The results of the tribological evaluation suggest that both samples (BL1 and BL2) have promising potential for applications in lubricating machines.

Synthesis and Frictional Characteristics of Bio-Based Lubricants Obtained from Fatty Acids of Castor Oil

The depletion of oil reserves and concerns about the environmental impact of the use and incorrect disposal of mineral lubricants have been promoting the development of bio-based lubricants. In this study, biolubricants obtained from fatty acids of castor oil were synthesized by esterification (>wt.%93), epoxidation (>wt.%92), and oxirane ring opening reactions using water (>wt.%92) or 2-ethylhexanol (>wt.%94) as nucleophilic agents. The frictional characteristics of the synthesized samples were obtained through tribological tests performed in a four-ball tester and compared with a commercial mineral oil. The sample obtained through oxirane ring opening with water showed the best frictional performance (FC = 0.0699 ± 0.0007) among the prepared samples, with equivalent wear rate (WSD = 281.2 ± 5.54 μm) and ca. 20% lower friction coefficient when compared to the commercial mineral oil, indicating its great potential for replacing mineral fossil oils.

Synthesis, theoretical studies and viscosity correlations of ricinoleic acid based methyl ester soap solution

The use of vegetable oils for industrial applications needs chemical modification to improve its properties. For coolants and lubricant applications, the viscosity of vegetable oils plays a vital role which decides the heat dissipation and flow characteristics of vegetable oils. In this study, the viscosity prediction modeling of binary mixtures has been made using refutes empirical relations. The blend viscosity from the model depends on the blend ratios of the unsaturated fatty acids in castor oil and methanol. This blending of castor oil and methanol follows KOH assisted transesterification process to form Fatty Acid Methyl Ester (FAME) soap solution. The transesterified blend mixes have been experimentally analyzed for viscosity using Brookfield viscometer. The measured values of viscosities of the blend mix have been compared with viscosities obtained from refutes binary blend mix model. The percentage deviation between the experimental viscosities and Refutes viscosity prediction model is about 10.76%. The prepared FAME soap solution can be used as coolants and lubricants in manufacturing industries.

Esters from castor oil functionalized with aromatic amines as a potential lubricant

AbstractVegetable oils are very promising alternatives to fossil lubricants due to their abundance, low cost, excellent performance, and environmental friendliness. Due to its multifunctional structure, castor oil is an excellent precursor in the synthesis of new biolubricants. However, it showed poor thermal‐oxidative stability and a higher pour point. This study used castor oil fatty acids prepared by transesterification (EHRO), epoxidation (TEPO), and oxirane ring opening with the aromatic amines aniline (ANIL) andp‐anisidine (ANIS). The chemical structure of these oils was verified by1H and13C NMR analysis, and mass spectrometry. Measurements show that the presence of an aromatic amine increases the viscosity resulting in 172 (ANIL) and 199 (ANIS) cSt at 40°C, but reduces viscosity index to 16 and 1, respectively. In addition, the amine groups can scavenge radicals increasing their thermal and oxidative stability. These products do not oxidize copper, and tribological analysis reveals that ANIS has the lowest torque with wear equivalent to commercial mineral lubricant NH‐140.

Achieving superlubricity using selected tribo-pairs lubricated by castor oil and unsaturated fatty acids

Systematic friction tests have been performed to unveil the key factors for reaching superlubricity (CoF < 0.01) in the presence of unsaturated fatty acid-based lubricants under boundary lubrication regime. The impact of different tribo-pairs and lubricants has been investigated. When the counterpart is steel, results show that a hydrogen-free DLC coating is indispensable to achieve superlubricity in castor oil. Among pure unsaturated fatty acids as lubricants, oleic and ricinoleic acid gave superlow friction but linoleic acid is not recommended to lubricate steel/a-C contact due to the occurrence of high friction and wear. X-ray photoelectron spectroscopy (XPS) and X-Ray-Excited Auger Electron Spectroscopy (XAES) analyses reveal that hydrogen-free carbon can activate two pathways to passivate surface and to achieve superlubricity with fatty acid-based lubricants (i) carbon re-hybridization by forming a high-density sp2 carbon network and (ii) –(CH2-CH2)n– oligomers formation on top surface. At the opposite, linoleic acid hinders the formation of –(CH2-CH2)n– oligomers and oxidizes carbon surfaces.

Novel mannosylerythritol lipid biosurfactant structures from castor oil revealed by advanced structure analysis.

Mannosylerythritol lipids (MELs) are glycolipid biosurfactants produced by fungi of the Ustilaginaceae family in the presence of hydrophobic carbon sources like plant oils. In the present study, we investigated the structural composition of MELs produced from castor oil using seven different microorganisms and compared them to MEL structures resulting from other plant oils. Castor oil is an industrially relevant plant oil that presents as an alternative to currently employed edible plant oils like rapeseed or soybean oil. The main fatty acid in castor oil is the mono-hydroxylated ricinoleic acid, providing the possibility to produce novel MEL structures with interesting features. Analysis of the produced MELs from castor oil by different chromatographic and mass spectrometry techniques revealed that all seven microorganisms were generally able to integrate hydroxylated fatty acids into the MEL molecule, although at varying degrees. These novel MELs containing a hydroxy fatty acid (4-O-[2′-O-alka(e)noyl-3′-O-hydroxyalka(e)noyl-4′/6′-O-acetyl-β-D-mannopyranosyl]-erythritol) were more hydrophilic than conventional MEL and therefore showed a different elution behavior in chromatography. Large shares of novel hydroxy MELs (around 50% of total MELs) were found for the two MEL-B/C producing species Ustilago siamensis and Ustilago shanxiensis, but also for the MEL-A/B/C producer Moesziomyces aphidis (around 25%). In addition, tri-acylated hydroxylated MELs with a third long-chain fatty acid esterified to the free hydroxyl group of the hydroxy fatty acid were identified for some species. Overall, production of MEL from castor oil with the investigated organisms provided a complex mixture of various novel MEL structures that can be exploited for further research.

Synthesis and design of polyurethane and its nanocomposites derived from canola‐castor oil: Mechanical, thermal and shape memory properties

AbstractThe recent global pandemic and its tremendous effect on the price fluctuations of crude oil illustrates the side effects of petroleum dependency more evident than ever. Over the past decades, both academic and industrial communities spared endless efforts in order to replace petroleum‐based materials with bio‐derived resources. In the current study, a series of shape memory polymer composites (SMPC's) was synthesized from epoxidized vegetable oils, namely canola oil and castor oil fatty acids (COFA's) as a 100% bio‐based polyol and isophorone diisocyanate (IPDI) as an isocyanate using a solvent/catalyst‐free method in order to eventuate polyurethanes (PU's). Thereafter, graphene oxide (GO) nanoplatelets were synthesized and embedded in the neat PU in order to overcome the thermomechanical drawbacks of the neat matrix. The chemical structure of the synthesized components, as well as the dispersion and distribution levels of the nanoparticles, was characterized. In the following, thermal and mechanical properties as well as shape memory behavior of the specimens were comprehensively investigated. Likewise, the thermal conductivity was determined. This study proves that synthesized PU's based on vegetable oil polyols, including graphene nanoparticles, exhibit proper thermal and mechanical properties, which make them stand as a potential candidate to compete with traditional petroleum‐based SMPC's.

Effectiveness of Vegetable-Oil Fatty Acids as Antiwear Additives for Diesel Oils

The current study is devoted to the use of vegetable-oil fatty acids (FAs) as lubricity additives for modern diesel fuels with ultra-low sulfur contents. The effectiveness of liquid castor, linseed, coconut, and sunflower oils in the base components of diesel fuels for hydrotreating, hydrocracking, and hydroisomerization is comparatively evaluated. It is established that all investigated vegetable-oil FAs are effective anti-wear additives as compared to a commercially available additive while FAs of castor oil, which consist of 90% ricinoleic acid, are most effective as anti-wear additives.

Fatty Acid Profiles and Fuel Properties of Oils from Castor Oil Plants Irrigated by Microalga-treated Wastewater

Microalgae can function as a bio-fertilizer and a bio-filter for wastewater treatment, thus allowing the re-use of wastewater for the irrigation of plants that produce abundant bio-oils and for the irrigation of low-quality soils. Chlorella vulgaris was grown in Om El-Resh drain water as growth medium, after enrichment with nitrogen and phosphorous. Castor seeds were cultivated in a greenhouse at the Algal Biotechnology Unit, National Research Centre, Egypt. Fifteen days later, transplants were irrigated by untreated wastewater (WW); wastewater treated with microalgae (WW+A); or wastewater treated with microalgae followed by removal of microalgae (WW-A). Oil extraction was performed by seed warming and grinding with n-hexane, followed by soaking, filtration, and passage through Silica gel 60. Esterification was performed, and then fatty acid methyl esters (FAMEs) were determined. The results indicated that the wastewater treatment markedly affected seed oil content. The WW+A treatment led to the highest seed oil yield (41.8%), followed WW-A treatment (28.14%), and the WW treatment (25.12%). FAME analysis indicated that the presented fatty acids of castor oil were C16 and C18 and ricinoleic acid (C18:1) was the most abundant (83.1 to 84.63%). In spite of the higher seed oil content when plants were grown in WW+A, there were differences in the fuel proprieties of seed oils in the different groups, based on American Society for Testing and Materials criteria. Our results suggest that wastewater can be successfully used for irrigation of soils that have poor fertility to produce bio-oils during land reclamation.

Physicochemical Properties and Antibacterial Activity of Castor Oil and Its Derivatives

Castor oil is vegetable oil sourced from castor seeds (Ricinus communis Linn). The main content of fatty acids in castor oil are ricinoleic acid (92%), oleic acid (3.53%), linoleic acid (2.90%), stearic acid (1.02%), and myristic acid (0.55%). Research on the antibacterial activity of castor oil and ricinoleic fatty acid has been carried out but for the K-soap and fatty acids methyl esters of castor oil have not been conducted. This research aims to produce castor oil derivatives, namely K-soap, free fatty acids (FFAs) and fatty acids methyl esters of (FAMEs) and evaluate their antibacterial activity. The results of the study included (1) K-soap (solid, white, melting point 168–175°C), (2) free fatty acids (liquid, yellow, boiling point 210°C, density 0.98 g.mL−1, refractive index 1.46, viscosity 693.22 cSt, and the value of acids, saponification, and esters are 145.88, 294.52, 148.64), (3) fatty acids methyl esters (liquid, yellow, boiling point 170°C, density 0.98 g.mL−1, refractive index 1.46, viscosity 27.31 cSt, and the value of acids, saponification and esters are 0.33, 392.7, 392.37). K-soap, free fatty acids, and methyl esters from castor oil have antibacterial activity against Escherichia coli and Staphylococcus aureus bacteria.

Chemical modification of castor oil fatty acids (Ricinus communis) for biolubricant applications: An alternative for Brazil’s green market

Plants oils have been increasingly gaining acceptance in world markets, due to their great potential as raw material to replace conventional mineral oils for formulation of lubricants. In this study, samples of new potential bio-based lubricant molecules were synthesized from castor oil fatty acids. The synthesis occurred in three steps: esterification with 2-ethyl-1-hexanol, epoxidation and opening of oxirane rings with different nucleophilic agents: 1-butanol (BIOBUT) and water (BIOWAT). The main objective was to study the influence of hydroxyl groups and branching level on physicochemical properties and thermal degradation of samples. The products obtained in each step were characterized by 1H NMR and their physicochemical properties. The results indicated that the less polar samples (BIOBUT) exhibited a better low-temperature performance (PP −48 °C). Furthermore, BIOBUT has superior oxidation stability (IP 4.22 h) compared to BIOWAT (IP 3.27 h). However, the BIOWAT showed a higher viscosity values (> 470 mm2/s at 40 °C). Thermogravimetric analyses have indicated that BIOWAT shows better thermal stability. Finally, the activation energy determined for the first thermal event for BIOWAT (151 kJ.mol−1) was higher than BIOBUT.

Performance Evaluation and Biodegradation Study of Polyvinyl Chloride Films with Castor Oil‐based Plasticizer

AbstractIn the present study, a renewable resource‐based plasticizer was synthesized by the lipase‐catalyzed esterification reaction of furfuryl alcohol (FA) and castor oil fatty acid (COFA). The resultant ester (FA‐COFA ester) was used as secondary plasticizers to the polyvinyl chloride (PVC) films. The PVC films were formulated using the combination of a conventional plasticizer di‐butyl phthalate (DBP) and FA‐COFA ester as a secondary plasticizer at different concentrations. Films were characterized by X‐ray diffraction analysis, scanning electron microscopy, thermal analysis, mechanical performance, and migration stability. A biodegradability study of the PVC films showed increased degradability with increasing concentration of the FA‐COFA ester in the PVC film. The study showed that ester of FA and COFA could be a substitute of DBP by as much as 80% of the total plasticizer with improved elongation and tensile properties, and such a kind of sustainable resource‐based PVC blend films could be used as a good packaging material with biodegradable property.

Effect of branching in hyperbranched alkyd on the performance of alkyd polyurethane coating

ABSTRACTHyperbranched alkyd was synthesized by single‐step approach using trimethylolpropane, mono pentaerythritol as core material, and 2,2‐bis(methylol)propionic acid (DMPA), a combination of dehydrated castor oil fatty acid and coconut oil fatty acid as chain extender. A series of hyperbranched alkyds were prepared at different degree of branching in the alkyd structures by changing the amount of DMPA in the alkyd resin formulation. The resins were characterized by Fourier transform infrared and 1H‐nuclear magnetic resonance (NMR) spectroscopic technique. These hyperbranched alkyds were converted into polyurethane coating after reaction with hexamethylene diisocyanate trimer at a definite ratio in the presence of dibutyltin dilaurate as a catalyst. The effect of branching and polymeric chain entanglement on the glass transition temperature, Tg of the alkyd polyurethane coating (APUC) was studied by differential scanning calorimetry technique. The performance of such APUC in terms of gloss, gloss retention under accelerated QUV radiation, natural outdoor exposed condition, mechanical, and corrosion resistance properties were enhanced with the increase of polymeric chain entanglement, i.e., compactness or higher order of branching in the alkyd resin structure. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45835.

Influence of pore size and loading for Nb2O5/SBA-15 catalysts on synthetic ester production from free fatty acids of castor oil

In this study, the influence of the pore size in mesoporous silica (SBA-15) and the loading of niobium oxide species (Nb2O5) have been evaluated on the esterification reaction of free fatty acids from castor oil to obtain products that can be used as bio-based lubricant feedstocks. Characterization techniques such as XRD, N2 sorption, Raman spectroscopy, NH3-TPD, XPS and TEM have been employed to characterize the synthesized catalysts, demonstrating the high dispersion of the niobia species. The catalytic results showed that the SBA-15 support with an average pore size of 8.5nm and a loading of 12wt.% of Nb2O5 was the best catalyst to obtain higher conversion values in the esterification reaction of ricinoleic acid. This fact was probably due to the pore diameter of this catalyst was the most suitable for the diffusion of reagents and products. The textural properties were more relevant than the acidic properties for Nb2O5 supported on silica catalysts. The reuse data indicated that the conversion values decrease after each cycle probably due to the formation of carbonaceous deposits in the active sites, discarding the niobium leaching which is negligible. The catalytic activity could be almost thoroughly recovered by using a thermal regeneration treatment.

Catalytic Hydrocracking -Hydrogenation of Castor Oil Fatty Acid Methyl Esters over Nickel Substituted Polyoxometalate Catalyst

Catalytic Hydrocracking -Hydrogenation of Castor Oil Fatty Acid Methyl Esters over Nickel Substituted Polyoxometalate Catalyst

Studies on performance evaluation of a green plasticizer made by enzymatic esterification of furfuryl alcohol and castor oil fatty acid

The esterification of furfuryl alcohol (FA) and castor oil fatty acid (COFA) at 3:1 molar ratio, by immobilized Candida antarctica Lipase B (NS 435 from Novozyme) in a solvent free system gave a maximum yield of 88.64% (%w/w) at 5h. Performance of the FA-COFA ester plasticized Ethyl Cellulose (EC) films were evaluated by surface morphologies, XRD analysis, mechanical properties,thermal properties, water vapor permeability and migration stability test. It was an effective plasticizer with better mechanical properties and thermal stability at the increasing concentration of FA-COFA ester (15–25%) containing EC film, than the traditional plasticizer, i.e; dibutyl phthalate (DBP) in producing good quality films. Chemical structure and the intermolecular interactions between FA-COFA ester and ethyl cellulose chains were the causative agents of these outstanding performances. Therefore, this FA-COFA ester, with significant plasticizing property, at a certain concentration, can be a substitute of DBP.

Synthesis, Characterization, and Evaluation of Castor Oil-Based Acylated Derivatives as Potential Lubricant Base Stocks

Synthesis, characterization, and evaluation of a series of novel acylated derivatives of castor oil as biolubricant base stocks are described. The acylated derivatives of castor oil, castor oil fatty acid methyl and 2-ethylhexyl esters were synthesized using different anhydrides (C1–C6) in about 90–95% yield. All the products were structurally characterized using NMR and IR spectral data. The acylated products were evaluated for their physicochemical and lubricant properties. Although these products belong to group V, based on viscosity index (130–156), acylated derivatives of castor fatty acid alkyl esters belong to group III, the category of base fluids as per API classification. The acylated products exhibited excellent pour point (−21 to −39 °C) and flash point (174–280 °C). The hexanoylated and butanoylated esters of castor oil exhibited excellent flash points of 280 and 272 °C, respectively. The air release value was found to be excellent in the range of 0.38–0.99 min, and NOACK volatilities in the range of 3.25–3.92%. The other lubrication properties such as load carrying capacity, and emulsion stability were found to be good. Therefore, these derivatives will have utility in hydraulic and metal working fluids and other industrial fluids with their wide range of properties.