Neat Vegetable Oils Research Articles

Experimental Studies on the Jatropha-Biogas Dual Fuel Engine

In the current study, experiments were conducted on a compression ignition engine using neat vegetable oil (Jatropha oil) and biogas in the dual-fuel mode. A mono-cylinder, 4-stroke, direct injection, air-cooled diesel engine producing an output power of 4.4 kW at 1500 rpm was used to carry out the experiment. This engine was modified to operate in a dual fuel mode at 100% and 50% load conditions. From the result, the jatropha oil operation resulted in reduced thermal efficiency and increased smoke and hydrocarbon emissions. Brake thermal efficiency has been observed as 31% and 27% with neat-diesel fuel and jatropha oil respectively. While operating the engine in dual fuel mode, the thermal efficiency was observed to be inferior and increase in hydrocarbon emission, with a considerable reduction in smoke compared with single fuel operation. The key reason for lower thermal efficiency during dual fuel operation is mainly due to the presence of carbon dioxide in primary biogas fuel. Overall, it was concluded that adopting the dual fuel mode with vegetable oil as pilot fuel will result in reduced emissions and improvement in efficiency at medium and high outputs.

Environmental Sustainability Achievement on Diesel Engine Emissions Using Mahua Biodiesel Influenced by Graphite

Aims: To assess the performance and emission parameters of graphite-included mahua biodiesel at various proportions such as 10 ppm, 40 ppm, and 70 ppm. Background: The fuels derived from petroleum are harmful to the environment and deplete traditional energy sources. The discovery of alternative fuels has paved the way for various options. Studies suggest replacing diesel with vegetable oils. Neat vegetable oil has a high viscosity and low volatility characteristics, making it unsuitable for diesel engines. Methods: Transesterification of mahua seed oil produces biodiesel with graphite distributed in varying concentrations by ultra sonification. Mahua biodiesel shows reduced viscosity compared to neat vegetable oil, and it will be used as diesel in diesel engines. Graphite nanoparticles contained in mahua biodiesel mix (B30) indicate improved brake thermal efficiency, reduced brake-specific fuel consumption, and reduced carbon monoxide, unburned hydrocarbon, nitrogen oxide, and smoke density. Conclusion: The results of this investigation showed that multi-cylinder diesel engines with direct injection can use optimal blend B30, which incorporates graphite nanoparticles, without requiring any modifications to the engine.

Boundary Lubricity of Vegetable-Oil-Derived Trimethylolpropane (TMP) Ester

Vegetable-oil-based biolubricants are an excellent alternative to conventional lubricants. Instead of focusing on novel feedstocks, these biolubricants should be further elucidated based on their fatty acid composition, which influences their tribological properties. Therefore, the study utilises gene expression programming (GEP) to derive a boundary lubricity model for vegetable-oil-derived trimethylolpropane (TMP) esters, considering the fatty acid composition (saturation and monounsaturation levels), load and speed. Neat vegetable oil and blends from seven feedstocks are selected following a wide range of fatty acid profiles to synthesise TMP esters using a two-stage transesterification process. The TMP esters are spin-coated on wear discs that are subsequently rotated against a ball using a purpose-built tribometer. The frictional performance of the TMP esters with balanced saturation and monounsaturation levels of fatty acid are measured to improve it at higher speeds. The GEP model is statistically evaluated by adopting the friction data, a showing good generalisation and predictability capability. The model demonstrates that friction decreases with increasing saturation levels of the TMP ester. The GEP model for vegetable oil TMP esters allows for the tribological performance prediction of TMP esters following the fatty acid profile, providing a platform to optimise such biolubricant for desired applications.

A novel application of a geotechnical soil stabilization technology for improved delivery of remedial amendments

AbstractAccelerating the remediation of contaminants that have diffused into low‐permeability (low‐k) geologic units such as silts and clays is a key need for the groundwater remediation industry. Injection‐based remedial technologies are often ineffective because the injected amendments are more likely to influence transmissive media (sands and sandy silts) and generally do not penetrate low‐k units. While some emerging technologies are now being tested, they are often expensive or have other technical limitations (e.g., installation depth and rate of amendment emplacement). To address the problem of treating contaminants in low‐k media, a geotechnical technology called the “Grout Bomber” (Keller North America) was repurposed for an environmental application to emplace ~800 vertical “reaction columns” containing zero valent iron (ZVI), sand, and neat vegetable oil for the treatment of chlorinated volatile organic compounds (CVOCs) in lean clays and sandy clays. The reaction columns were closely‐spaced (2–3 ft apart) to greatly accelerate the back diffusion of CVOCs from the low‐k media to the reaction columns where contact with ZVI and vegetable oil promotes abiotic and biotic reductive dechlorination of CVOCs, respectively. Overall, 35 tons of ZVI were emplaced into the 5200 cubic yard (yd3) (~4000 m3) source zone during the project. Key benefits of this technology include rapid installation (average of 107 reaction columns per day), ease of remediation amendment mixing, consistent amendment dosing, and relatively low unit installation costs ($71 per cubic yard of treatment zone). It should be emphasized that this application of the Grout Bomber relies on diffusion of contaminants into the reaction columns from the surrounding low‐k media—a process that occurs slowly over years to decades. A planning‐level model showed that installation of closely spaced vertical reaction columns in a TCE‐laden clay unit reduced the time to achieve maximum contaminant levels from greater than 500 years to approximately 26 years. Groundwater monitoring confirmed the establishment of a concentration gradient between the reaction columns which promotes diffusion of CVOCs toward the reaction columns. The presence of dissolved acetylene and gaseous “higher coupling” products (>C3) provide further evidence of ongoing abiotic reductive dechlorination within the reaction columns.

Influence of Cissus quadrangularis as biofuel additive on the performance of VCR diesel engine fueled with palm oil

Although many bio-fuels (neat vegetable oils) including palm oil, were found suitable for diesel replacement in internal combustion engines, none of them ever tested so far had better performance than diesel and therefore bio-fuels are commercially not viable to date. Hence in this research work, a novel bio-fuel additive derived from naturally available herbal species known as Cissus quadrangularis (Vajravalli) has been proposed. This herbal juice in liquid form is added with palm oil in different volumetric proportions and is used as fuel to test the performance of single-cylinder, 4-stroke, compression-ignition water-cooled, direct-injection, variable compression ratio engine. The experimental results witness a significant advancement in the brake thermal efficiency of the engine operating with palm oil using Cissus quadrangularis as an additive when it is compared to neat palm oil fuel operation. At rated load with an engine compression ratio of 18, the fall in brake thermal efficiency for palm oil operation is 7% in comparison to diesel operation. This reduction in BTE has been improved to only 3% for 2V98P fuel. Also, there is a decrease in brake specific fuel consumption. Furthermore, the performance characteristics of 2V98P fuel are in close concurrence with diesel operation. The maximum mechanical efficiency obtained at rated load for palm oil, 1V99P, 2V98P, 3V97P, and 4V96P fuels is respectively 7%, 5.8%, 4.8%, 4%, and 3% greater than that of diesel. Also, the exhaust gas temperatures obtained for 2V98P, 3V97P, and 4V96P are less than that of diesel operation while for palm oil and 1V99P it is greater than that of diesel. The maximum BTE and minimum BSFC obtained for 2V98P fuel is 32.05% and 0.3255 kg/kWh respectively as against 32.8% and 0.3126 kg/kWh for the diesel operation at a rated load with a compression ratio of 20.

Effect of Diesel Fuel-Coconut Oil-Butanol Blends on Operational Parameters of Diesel Engine

The global concentration of greenhouse gasses in the atmosphere is increasing as well as the emissions of harmful pollutants. Utilization of liquid biofuels in combustion engines helps to reduce these negative effects. For diesel engines, the most common alternative fuels are based on vegetable oils. Blending neat vegetable oils with diesel and/or alcohol fuels is a simple way to make them suitable for diesel engines. In this study, coconut oil was used in ternary fuel blends with diesel and butanol. Coconut oil is a potentially usable source of renewable energy, especially in the Pacific, where it is a local product. Diesel fuel-coconut oil-butanol fuel blends were used in concentrations of 70%/20%/10% and 60%/20%/20%, and 100% diesel fuel was used as a reference. The effect of the fuel blends on the production of harmful emissions, engine smoke, performance parameters, fuel consumption and solid particles production was monitored during the measurement. The engine was kept at a constant speed during the measurement and the load was selected at 50%, 75% and 100%. From the results, it can be stated that in comparison with diesel fuel, specific fuel consumption increased with a positive effect on the reduction of engine smoke.

A comparative analysis of different methods to improve the performance of rubber seed oil fuelled compression ignition engine

There is a need to find suitable substitutes for the petroleum based fuels as the conventional fuels are decreasing in order in recent years. Vegetable oils are attractive as an alternative fuel for diesel engines as they are renewable and can be used in engines without employing any major modifications. The main problems with the use of neat vegetable oils in diesel engines are high smoke levels and relatively low thermal efficiency due to high viscosity and carbon residue as compared to diesel. In this work various methods for improving the performance of rubber seed oil (RSO) fuelled diesel engine are compared and discussed. Dual fuel operation with hydrogen, ethanol and DEE resulted in higher brake thermal efficiency. Oxides of nitrogen (NOx) level are lowest with neat RSO engine operation. It increases about 36% for dual fuel operation with hydrogen and 32% with DEE injection compared to neat RSO. Smoke emission reduces from 6.1 Bosch Smoke Unit (BSU) for neat RSO operation to 3.8 BSU for hydrogen induction, 4 BSU for DEE injection and 3.4 BSU for ethanol injection which is the lowest value compared to all other test fuels. Peak pressure and rate of pressure rise are higher for all the methods as compared to neat RSO operation. Ignition delay is higher for neat RSO operation; it further increases with dual fuel operation with hydrogen, LPG and ethanol. It is concluded that dual fuel operation with hydrogen and DEE is effective in improving the performance of neat rubber seed oil in compression ignition engine operation.

Fully bio‐based thiol‐ene photocured thermosets from isosorbide and tung oil

AbstractDirect preparation of coatings from neat vegetable oils without any pretreatment or modification is an elegant way of demonstrating the potential of renewable sources and it is also in line with the principles of Green Chemistry. In this work, photocured coatings were prepared from tung oil (TO), hazelnut oil (HN), and isosorbide. First, a dithiol derivative of isosorbide (ISTMP) was synthesized and then mixed with TO, HN, and a cationic photoinitiator. For comparison, formulations were also prepared by using two different commercial thiol compounds. Coating formulations were applied onto glass substrates and cured under UV light where oxidative polymerization and photoinitiated thiol‐ene addition reactions took place concomitantly. Double bond conversion percentages, thermal degradation properties, water contact angles, and surface hardness of the coatings were determined. Furthermore, a model reaction between ISTMP and oleic acid was performed to prove that ISTMP reacts with the fatty acid. ISTMP containing formulation displayed a fast initial double bond conversion and its water contact angle value was found as 88 ± 3°. Rigid and thermally stable isosorbide ring improved both the thermal properties and the surface hardness of the coatings.

Comparative study of properties and fatty acid composition of some neat vegetable oils and waste cooking oils

Abstract Vegetable oils have been used as a feedstock for fatty acid methyl ester (FAME) production. The high cost of neat vegetable oil and its impact on food security have necessitated its replacement as a feedstock for FAME by used vegetable oil, also known as waste cooking oil (WCO). This study compares the properties and fatty acid (FA) compositions of samples of neat vegetable oil with those of samples of WCO, collected from restaurants and takeaway outlets at the point of disposal. The samples were subjected to property determination and pyrolysis gas chromatography mass spectrometer (PYGCMS) analysis. Analysis showed that degree of usage and the type of food items originally fried in the oil substantially affected its properties and FA composition. Density of neat vegetable oil varied between 904.3 and 919.7 kg/m3 and of WCO between 904.3 and 923.2 kg/m3. The pH of neat vegetable oil varied between 7.38 and 8.63 and of WCO between 5.13 and 6.61. The PYGCMS analysis showed that neat palm oil contains 87.7% unsaturated FA and 12.3% saturated FA, whereas neat sunfoil contains 74.37% saturated FA and 25% polyunsaturated FA. Generally, neat vegetable oils consisted mainly of saturated FAs and polyunsaturated FAs, whereas the WCO contained mainly of saturated FAs and monounsaturated FAs. This research confirms the suitability of WCO as feedstock for FAME.

Biofuel production from Pachira aquatic Aubl and Magonia pubescens A St-Hil: Physical-chemical properties of neat vegetable oils, methyl-esters and bio-oils (hydrocarbons)

Two perennial tree species Pachira aquatica Aubl (PA) and Magonia pubescens A St-Hil (MP), both being endemic to Brazil, were studied as potential sources for biofuels production. The main benefits of those sources is the lack of competition with the food market and the preservation of native vegetation. The chemical composition and the physical-chemical properties of the oils extracted from both species were evaluated. Furthermore, their oils were processed to produce biofuels using two approaches: obtaining mixtures of methyl fatty acid esters (biodiesel) and mixtures of hydrocarbons (bio-oil). The physical-chemical properties of the biodiesels obtained from PA and MP are compatible with diesel engines. The bio-oils obtained from both sources, despite not being completely deoxygenated, displayed physical-chemical properties acceptable for diesel engines fuel. The possibility of obtaining two kinds of fuels with suitable properties is a good sign for the exploration of those trees.

Combined Falling Drop/Open Port Sampling Interface System for Automated Flow Injection Mass Spectrometry.

The aim of this work was to demonstrate and to evaluate the analytical performance of a combined falling drop/open port sampling interface (OPSI) system as a simple noncontact, no-carryover, automated system for flow injection analysis with mass spectrometry. The falling sample drops were introduced into the OPSI using a widely available autosampler platform utilizing low cost disposable pipet tips and conventional disposable microtiter well plates. The volume of the drops that fell onto the OPSI was in the 7-15 μL range with an injected sample volume of several hundred nanoliters. Sample drop height, positioning of the internal capillary on the sampling end of the probe, and carrier solvent flow rate were optimized for maximum signal. Sample throughput, signal reproducibility, matrix effects, and quantitative analysis capability of the system were established using the drug molecule propranolol and its isotope labeled internal standard in water, unprocessed river water and two commercially available buffer matrices. A sample-to-sample throughput of ∼45 s with a ∼4.5 s base-to-base flow injection peak profile was obtained in these experiments. In addition, quantitation with minimally processed rat plasma samples was demonstrated with three different statin drugs (atorvastatin, rosuvastatin, and fluvastatin). Direct characterization capability of unprocessed samples was demonstrated by the analysis of neat vegetable oils. Employing the autosampler system for spatially resolved liquid extraction surface sampling exemplified by the analysis of propranolol and its hydroxypropranolol glucuronide phase II metabolites from a rat thin tissue section was also illustrated.

Effect of fuel inlet temperature on cottonseed oil–diesel mixture composition and performance in a DI diesel engine

Vegetable oils are receiving a lot of attraction as alternative engine fuels as they are renewable. The main problems with the use of neat vegetable oils in direct injection (DI) diesel engines are higher viscosity and relatively lower thermal efficiency as compared to diesel fuel. In this investigation the cotton seed oil (CSO) has been considered as an alternative fuel for the compression ignition (C.I.) engine. The viscosity of this oil is decreased by blending with diesel and preheating the CSO–diesel blends to reduce the viscosity further. The mixture of varying proportions of cotton seed oil and diesel were prepared and their viscosities at various inlet temperatures were calculated and the performance and emission levels of these mixtures are compared with diesel fuel. The performance of the engine using preheated blends and cottonseed oil were studied using a single cylinder diesel engine. Significant improvement in engine performance is observed with preheated CSO and diesel mixture compared to neat CSO. Test results show that there is a marginal increase in the brake thermal efficiency of the engine, as the fuel inlet temperature of the blend and the amount of diesel in the blend increases. It is increases from 28% to the maximum of 30.5% with preheated CSO and diesel mixture of 40%. The smoke, carbon monoxide (CO) and unburnt hydrocarbons (HC) emissions of the engine is also less with the preheated blends. Smoke emission reduces from 3.9 Bosch smoke unit (BSU) to 3.5 Bosch smoke unit (BSU) which is very close to diesel smoke value of 3.4 BSU. Heat release rates indicated an increase in combustion rate with preheated mixtures. The cylinder peak pressure increases from 70.4 bar to 72.5 bar for optimum preheated mixture (60% CSO and 40% diesel at 343 K). From the engine test results it has been established that 60% of cotton seed oil at 343 K can be substituted for diesel.

The Tribological Characteristics of RBD Palm Olein with Jatropha Oil Blend Using Four-Ball Tribotester with Different Normal Loads

Vegetable oils are bio-fluids that could replace petroleum-based products due to its environment friendly characteristics and becoming an important source of bio-lubricants. The great advantage of vegetable oils is that they are widely available, renewable source of bio-lubricants. Moreover, vegetable oil based lubricant have shown the potential to reduce carbon dioxide and hydrocarbon emissions when operated in engines. There are two ways to use vegetable oil as a bio-lubricant, either use directly the neat vegetable oil without any additives or use with certain blending ratio of the vegetable oil with mineral lubricant. In this paper, the influences of the normal load on the tribological characteristics for the blending of two types of vegetable oils were investigated and compared with commercial lubricant oil by the use of the four ball tribotester. The vegetable blends are RBD palm olein and Jatropha oil ratio of RBD40/J60. All experimental works were conforming to ASTM D4172. The results exhibited that the both blending of RBD palm olein and Jatropha oil has lower the wear scar of ball bearings and coefficient of friction compared to commercial lubricant oil. As a conclusion, the blending of RBD palm olein and Jatropha oil has better performance compared to commercial lubricant oil or neat RBD palm olein.

Green technology effect of injection pressure, timing and compression ratio in constant pressure heat addition cycle by an eco-friendly material

Present energy strategies focus on environmental issues, especially environmental pollution prevention and control by eco-friendly green technologies. This includes, increase in the energy supplies, encouraging cleaner and more efficient energy management, addressing air pollution, greenhouse effect, global warming, and climate change. Biofuels provide the panorama of new fiscal opportunities for people in rural area for meeting their need and also the demand of the local market. Biofuels concern protection of the environment and job creation. Renewable energy sources are self-reliance resources, have the potential in energy management with less emissions of air pollutants. Biofuels are expected to reduce dependability on imported crude oil with connected economic susceptibility, reduce greenhouse gases, other pollutants and invigorate the economy by increasing demand and prices for agricultural products. The use of neat paradise tree oil and induction of eco-friendly material Hydrogen through inlet manifold in a constant pressure heat addition cycle engine (diesel engine) with optimized engine operating parameters such as injection timing, injection pressure and compression ratio. The results shows the heat utilization efficiency for neat vegetable oil is 29% and neat oil with 15% Hydrogen as 33%. The exhaust gas temperature (EGT) for 15% of H2 share as 450°C at full load and the heat release of 80J/deg. crank angle for 15% Hydrogen energy share.

Investigation of Ionic Liquids as Novel Metalworking Fluids during Minimum Quantity Lubrication Machining of a Plain Carbon Steel

Metalworking fluids are a major cause of health hazards for operators apart from being sources of environmental pollution, thus necessitating research in dry and minimum quantity lubrication (MQL) machining. Ionic liquids are a relatively new family of environment-friendly chemicals that have significant potential to be employed as lubricants in MQL machining. This paper presents the results of preliminary studies in which three ionic liquids based on the 1-methyl 3-butylimidazolium cation were applied as additives to vegetable oil in MQL machining of AISI 1045 steel under interrupted orthogonal cutting conditions. The results show that the presence of even minute quantities of ionic liquids can significantly affect the machining process through reduction in cutting forces and surface roughness of the machined workpiece, as compared to dry cutting, conventional flood-cooled cutting, and MQL machining with neat vegetable oil.

Low Cost Modification Kit for Retrofitting on Small Diesel Engines to Run on Straight Vegetable Oils

Many varieties of vegetable oils do have characteristics similar to that of diesel derived from petroleum crude and can be used directly as fuel in diesel engines. But varieties of problems are encountered on prolonged use of vegetable oils in the existing design of engines. The problems encountered in the existing design of the engine while working with vegetable oil are mainly greater load on the fuel pump and injector due to higher viscosity; filter clogging and difficult filtration; difficult cold starting due to residual oil in the combustion chamber; and vegetable oil's reaction with fuel line material. To address these problems and for reducing the viscosity of vegetable oils, different strategies suggested are: Pyrolysis; Dilution; Microemulsion; and, Transesterification. Out of these, transesterification is mostly adopted as it gives the matching properties with that of diesel and hence can be used without many modifications in the existing engine (1). But, the chemistry of transesterification requires careful and precise working which is normally not possible at local level at user end and hence commercial and logistic loading of prices leaves the same unfeasible. With the major research effort dedicated to the area of biodiesel, a small number of researchers are advocating the extension of Rudolph Diesel's concept of neat vegetable oil as CI engine fuel. Schrimpff (2) compared straight vegetable oil (SVO) with Bio-diesel (BD) on the issues of production,

Tribological Investigation and the Effect of Karanja Biodiesel on Engine Wear in Compression Ignition Engine

Various biomass based resources, which can be used as an extender, or a complete substitute of diesel fuel may have very significant role in the development of agriculture, industrial and transport sectors in the energy crisis. Use of Karanja oil methyl ester biodiesel in a CI DI engine was found highly compatible with engine performance along with lower exhaust emission as compared to diesel fuel but with slightly higher NOx emission and low wear characteristics. The combustion related properties of vegetable oils are somewhat similar to diesel oil. Neat vegetable oils or their blends with diesel, however, pose various long-term problems in compression ignition engines. These undesirable features of vegetable oils are because of their inherent properties like high viscosity, low volatility, and polyunsaturated character. Pongamia methyl ester (PME) was prepared by transesterification process using methanol for long term engine operations. The physical and combustion-related properties of the fuels thus developed were found to be closer to that of the diesel. A neat biodiesel (PME) was selected as a fuel for the tribological study of biofuels. Two similar new engines were completely disassembled and subjected to dimensioning of various vital moving parts and then subjected to long-term endurance tests on neat biodiesel and diesel respectively. After completion of the test, both the engines were again disassembled for physical inspection and wear measurement of various vital parts. The lubricating oil samples drawn from both engines were subjected to atomic absorption spectroscopy (AAS) for measurement of various wear metal traces present. The additional lubricating property of biodiesel fuel due to higher viscosity as compared to diesel fuel resulted in lower wear of moving parts and thus improved the engine durability with a bio-diesel fuel. Results reported from AAS tests confirmed substantially lower wear and thus improved life for biodiesel operated engines. Keywords—Transesterification, PME, wear of engine parts, Metal traces and AAS.

Optimizations of Vane Height of Guide Vane Swirl and Tumble Device to Improve in Cylinder Airflow Characteristics of a Diesel Engine Running with Vegetable Oil

Generally, compression ignition engine operating on neat vegetable oil and its blend with diesel fuel experience a reduction of engine performance and increase in exhaust emissions due to higher viscosity and lower volatility of vegetable oil than diesel fuel. Vegetable oil is less prone to evaporate, diffuse and mix with the in-cylinder air which eventually reduces the combustion efficiency and produces more emissions of CO and unburned HC. Therefore, this research investigated the potential of guide vane swirl and tumble device (GVSTD) to guide the air entrance to create more organized turbulence inside the fuel injected region to enhance the mixing process of air and vegetable oil. In order to do so, a base model of 3D computational fluid dynamic of internal combustion engine simulation was developed, verified and then simulations were carried with different GVSTD models. The results of turbulent kinetic energy, velocity, vorticity and swirling strength were compared to determine the optimum vane height. This research found that the 2 mm vane height was the optimum vane height with 35° twist angle, four vanes being arranged perpendicularly to each other and 30 mm vane length. Other different heights of vanes also showed improvement but 2 mm height showed the highest number of improvements. This could be due to the airflow pattern in bowl-inpiston head shape was amplified by the airflow pattern produced by the guide vane of 2 mm vane height. The extra turbulence, swirl, vorticity and velocity in the fuel injected region created by the 2 mm height vane is expected to enhance the mixing of vegetable oils with air to improve combustion and reduce CO and unburned HC emissions.

Optical Investigation on Diesel Engine Fuelled by Vegetable Oils

In the present paper the combustion behaviour and soot generation of different neat vegetable oils on a direct injection optical diesel engine have been investigated using in-cylinder pressure based combustion analysis and high-speed two colour method. A single-cylinder optical diesel engine with an electronically controlled common-rail fuel injection system has been used for this study. Four different vegetable oils, Jatropha, Croton, Rapeseed and Sunflower oil, have been tested at 120MPa injection pressure and fuel temperatures of 60 and 90°C. All tests were performed at fixed injection timings and fixed engine speed at 1200 rev/min with pilot and main injection.The experimental results show that although all four bio-oils have very similar physiochemical properties, some differences in their combustion and soot generation behaviour have been observed. It was concluded that sunflower oil (SFO) had very good combustion properties at lower temperatures compared to other fuels. While croton oil (CO) did not have outstanding combustion behaviour at any conditions, the combustion of Jatropha oil (JO) was improved at higher fuel injection temperatures.

Sonochemistry: a simple and efficient route for biodiesel production from neat and blended vegetable oils using LDH-derived base catalysts

Different layered double hydroxides were synthesized by coprecipitation under low supersaturation and calcined to obtain mixed metal oxides that were tested as heterogeneous catalysts for ultrasound assisted transesterification of oils with methanol for the preparation of fatty acid methyl esters (or) biodiesel using <6:1 methanol:oil molar ratio. Among them, mixed oxides derived by calcining CaAl2-LDH at 700 °C (CaAl2700-CLDH) was the most active catalyst as inferred from its maximum basicity, elucidated by Hammett studies. Various vegetable oils (edible, non-edible and used cooking oils) were successfully transesterified with 80–90 % yield of FAME under ultrasound at 40 °C within 90 min. Under equivalent conditions, the yield of FAME (for sunflower oil) through conventional heating was only 9 % while under ultrasound was 63 %. A single step process was developed for biodiesel production from high free fatty acids (FFA) containing oils such as Jatropha oil by blending it with sunflower oil or used cooking oil (60/40 weight ratio) that gave 89 % yield of FAME in both cases under the optimized reaction conditions. CaAl2700-CLDH showed moderate reusability up to two cycles and decreased thereafter while its activity could be restored by recalcining the recovered catalyst at 700 °C.