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A detailed chemical kinetic model has been developed for supercritical water oxidation (SCWO) of methylamine, CH3NH2, providing insight into the intermediates and final products formed in this process as well as the dominant reaction pathways. The model was adapted from previous mechanisms, with a revision of the peroxyl radical chemistry to include imine formation, which has recently been identified as the dominant gas‐phase pathway in amine oxidation. The developed model can reproduce previous experimental data on methylamine consumption and major product formation to reasonable accuracy, although with deficiencies in describing the induction time. Our simulations indicate that oxidation of the •CH2NH2 radical to methanimine, CH2NH, is the major channel in methylamine SCWO, with subsequent hydrolysis of CH2NH providing the experimentally observed reaction products ammonia and formaldehyde. Integral‐averaged reaction rates were used to identify major reaction pathways, and a first‐order sensitivity analysis indicated that the concentration of CH3NH2 is most sensitive to OH radical kinetics. Overall, this work clarifies the importance of imine chemistry in the oxidation of nitrogen‐containing compounds and indicates that they are necessary to model these compounds in SCWO processes.

Pentanol is a long chain alcohol produced from renewable sources and considered as a promising biofuel as a blending component with diesel or biodiesel blends. However, the lower cetane number of alcohols is a limitation, and it is important to increase the overall cetane number of biodiesel fuel blends for efficient combustion and lower emission. In this consideration, ignition improver additive 2-ethylhexyl nitrate (EHN) were used at a proportion of 1000 and 2000 ppm to diesel-biodiesel-pentanol blends. Experiments were conducted in a single cylinder; water-cooled DI diesel engine operated at full throttle and varying speed condition. The thermal stability of the modified ternary fuel blends was evaluated through thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis, and the physic-chemical properties of the fuel as well as engine characteristics were studied and compared. The addition of EHN to ternary fuel blends enhanced the cetane number significantly without any significant adverse effect on the other properties. TGA and DSC analysis reported about the improvement of thermal characteristics of the modified blends. It was found that, implementing ignition improver make the diesel-biodiesel-alcohol blends more thermally stable. Also, the brake specific fuel consumption (BSFC), nitric oxides (NO) and smoke emission reduced remarkably with the addition of EHN. Introducing EHN to diesel-biodiesel-alcohol blends increased the cetane number, shorten the ignition delay by increasing the diffusion rate and improve combustion. Hence, the NO and BSFC reduced while, carbon monoxide (CO) and hydrocarbon (HC) emissions increased slightly.

A running automobile engine produces more friction and wear between its sliding components than an idle one, and thus requires lubrication to reduce this frictional effect. Biodiesel is an alternative diesel fuel that is produced from renewable resources. Energy studies conducted over the last two decades focused on solutions to problems of rising fossil fuel price, increasing dependency on foreign energy sources, and worsening environmental concerns. Palm oil biodiesel is mostly used in Malaysia. This study conducted engine performance and emission tests with a single-cylinder diesel engine fueled with palm and Calophyllum inophyllum biodiesel blends (PB10, PB20, PB30, CIB10, CIB20, and CIB30) at a full-load engine speed range of 1000–2400 rpm, and then compared the results with those of diesel fuel. Friction and wear tests were conducted using the four-ball tester with different temperatures at 40 and 80 kg load conditions and a constant speed of 1800 rpm. The average brake specific fuel consumption increased from 7.96% to 10.15% while operating on 10%, 20%, and 30% blends of palm and C. inophyllum biodiesel. The respective average brake powers for PB20 and PB30 were 9.31% and 12.93% lower compared with that for diesel fuel. PB20 produced relatively lower CO and HC emissions than the diesel and biodiesel blends. Diesel produced low amounts of NO X emission, and the CIB blend produced a lower frictional coefficient compared with the diesel and PB blends. PB30 showed high average FTP and low average WSD, both of which enhanced lubricating performance. An average metal element composition was found in PB20 under the 40 and 80 kg load conditions. PB20 showed lower worn scar surface areas compared with the diesel and biodiesel blends. Results indicated that PB20 has better engine performance, lower emission, and good lubrication properties compared with diesel and biodiesel blends. Thus, PB20 is suitable for use in diesel engines without the need for any engine modification.

The high cost of energy supplies and the growing concern over the dependency on fossil fuels have impelled many countries to search for renewable and alternative energy sources. The extensive use of fossil fuels for transportation and power generation all over the world have caused the supply of fossil fuels to continuously decrease and have aggravated environmental pollution. Searching for alternative fuels has become imperative to reduce pollution and address the problems on fossil fuels. Vegetable oil fuels, such as palm oil biodiesel, serve as alternative forms of energy and are currently being studied, particularly as a diesel fuel substitute. The purpose of this study is to review the potential of palm oil as an energy source and alternative diesel fuel in terms of its performance, environmental impact, wear characteristics, and economic considerations. Compared with other vegetable oils, palm oil is a relatively sustainable, environment-friendly, less expensive, and economically beneficial potential source of energy. Palm oil plantation and production is a major industry in Malaysia, contributing to the economic growth and development of the country. The properties of palm oil biodiesel, namely, high oxidation stability, good cold properties, cetane number, and higher viscosity, makes it a suitable diesel substitute. Compared with other vegetable oils and petroleum diesel fuels, palm oil is associated with better engine performance, higher specific fuel consumption, and shorter ignition delay. Use of palm oil also reduces exhaust emission of hydrocarbon, carbon monoxide, carbon dioxide, and smoke, but not oxide of nitrogen emissions. The higher viscosity of palm oil improves its lubricating properties and anti-wear characteristics, which are favorable for various engine components. Therefore, the aim of this study is to review various studies on palm biodiesel production from different countries and compare the findings of these studies with the situation in Malaysia. This study examines the economic aspects of using palm oil, as well as its effects on performance, emission, and wear characteristics. Palm biodiesel could be the candidate with the greatest potential in all aspects.

A comparative morphological analysis was performed on the exhaust particles emitted from a CI engine using different blending ratios of palm biodiesel at several operating conditions. It was observed from this experiment; peak particle concentration for PB10 at 1200 rpm is 1.85E + 02 and at 1500 rpm is 2.12E + 02. A slightly smaller amount of volatile material has found from the biodiesel samples compared to the diesel fuel sample. Thermogravimetric analysis (TGA) showed that the amount of volatile material in the soot from biodiesel fuels was slightly lower than that of diesel fuel. PB20 biodiesel blends reduced maximum 11.26% of volatile matter from the engine exhaust, while PB10 biodiesel blend reduced minimum 5.53% of volatile matter. On the other hand, the amount of fixed carbon from the biodiesel samples was slightly higher than diesel fuel. Analysis of carbon emissions, palm biodiesel (PB10) reduced elemental carbon (EC) was varies 0.75%–18%, respectively. Similarly, the emission reduction rate for PB20 was varies 11.36%–23.46% respectively. While, organic carbon (OC) emission rates reduced for PB20 was varied 13.7–49% respectively. Among the biodiesel blends, PB20 exhibited highest oxygen (O), sulfur (S) concentration and lowest silicon (Si) and iron (Fe) concentration. Scanning electron microscope (SEM) images for PB20 showed granular structure particulates with bigger grain sizes compared to diesel. Particle diameter increased under the 2100–2400 rpm speed condition and it was 8.70% higher compared to the low speed conditions. Finally, the results indicated that the composition and degree of unsaturation of the methyl ester present in biodiesel, play an important role in the chemical composition of particulate matter emissions.

The transportation, agricultural, and power sector of Bangladesh is largely dependent on fossil fuels that decrease day by day. The government has to import large volumes of fuel from foreign sources to meet the fuel demand for power production, causing a negative impact on the country's economy. Finding an alternative to fossil fuels is becoming the most urgent issue. Biodiesel can thus be a destined source to future energy demands. Increasing the usage of biodiesel will also decrease the global problem of environmental pollution, as fossil fuels are considered to be the major source of harmful emissions. Biodiesel is renewable, bio-degradable, non-toxic, technologically feasible, and can be used as a bio-lubricant In this study, the current energy scenario of Bangladesh, available potential biodiesel feedstocks, production process and engine fuel property, environmental impact, performance and emission characteristics on diesel engines, comparison of cost analysis, and future direction are discussed. Various research related to these feedstocks are performed in Bangladesh, which include an overview of biodiesel properties, engine performance, and emission parameters used in diesel engines. All types of biodiesel have similar functional properties compared with diesel fuel and can be successfully used in compression ignition engines. Biodiesel can thus serve as a subsequent replacement of non-renewable fossil fuels. Compared with diesel fuel, CO and HC emission were also low, but a slight increase in NOx was observed in some cases. One of the major advantages is that Bangladesh is a country with plenty of biodiesel feedstock sources, such as mustered, Jatropha curcas, rapeseed, sesame, castor, cottonseed, neem, algae, coconut, and groundnut In conclusion, producing biodiesel from different feedstocks is greatly possible and can thus assist in future energy needs. (C) 2015 Elsevier Ltd. All rights reserved.

The aim of this review is to study the opportunities and prospects of introducing diesel–biodiesel–ethanol/bioethanol blend as fuel in the existing diesel engines. The study is based on the engine emissions and its performance. The energy policies and the ever growing energy demand of the world, require an alternative to fossil fuels. In this quest, the diesel–ethanol blend or the diesohol blend might be a good option. But this blend possesses stability problem as well as inferior physicochemical properties when compared to diesel fuel and needs additives to remain stable. When biodiesel is used as an additive in this diesohol blend, it improves the physicochemical properties of the ternary blend, engine performance and also increases the renewable portion of the blend. First the engine performance and emissions data found by using diesel–biodiesel–ethanol/bioethanol ternary blends are accumulated. Then the results of the scientists and investigators are discussed to evaluate its potential as an alternative to fossil diesel fuel. The physicochemical properties of ternary blends are found to be almost similar to the diesel fuel. These ternary blends significantly reduce the PM (particulate matter) emissions from the diesel engine but the emissions of NO x (nitrogen oxides), soot and smoke, HC (hydrocarbon), CO (carbon monoxide), CO 2 (carbon dioxide) and the carbonyl compounds depend on the operating conditions of the engine and remain almost similar to the diesel fuel exhaust.

This study investigates of the production of calophyllum biodiesel (CIBD) from its crude oil and provides a comparative analysis of the blends of CIBD (CI20) and GTL fuel (G20) with diesel, including a combined blend (DCIG20) of CIBD, GTL and diesel, in the context of fuel properties, combustion, engine performance and emission characteristics. This combined blend was selected to aggregate the promising properties of the two alternative fuels, which is a pioneer investigation that involves GTL fuel. All of the blends were investigated in a four cylinder compression ignition engine. CIBD and CI20 showed improved fuel properties than their crude oil, and DCIG20 and G20 showed promising properties compared with the biodiesel blend. Combustion analysis showed that the peaks of both in-cylinder pressure and heat release rate (HRR) of G20 were slightly lower and occurred at later crank angles than those of diesel. Unlike G20, the other two blends demonstrated higher peak values of in-cylinder pressure and HRR than diesel, and DCIG20 showed lower peak values than CI20 in both cases. The peak locations of CI20 and DCIG20 were slightly advanced compared to those of diesel. The engine performance test results revealed an increase in brake thermal efficiency (BTE), and low Brake Specific Fuel Consumption (BSFC) and Brake Specific Energy Consumption (BSEC) in G20. The two other blends showed a decrease in BTE, but an increase in both BSFC and BSEC, when compared with diesel. Emission analysis results showed that all fuel blends exhibited a reduction in CO, HC and smoke emissions compared with diesel. In the case of NOx emission, both CI20 and DCIG20 showed high values, but G20 showed a significant decrease, when compared with diesel. DCIG20 exhibited an improvement in all of the performance–emission test parameters compared with CI20.

Biodiesel consists of long chain fatty acid esters derived from vegetable oils, animal fats, and used oils. Biodiesel contains different types, amounts, and configurations of unsaturated fatty acids, which are prone to oxidation. Biodiesel stability is affected by its interaction with atmospheric oxygen, light and temperature, storage conditions, and factors causing sediment formation. It can be classified broadly into three types: oxidation stability, thermal stability, and storage stability. Oxidative degradation occurs in biodiesel upon aerobic contact during storage, as well as upon contact with metal contaminants. Thermal instability focuses on the oxidation rate at higher temperatures, which is characterized by the formation of insolubles and increase in the weight of oil and fat. Storage stability is concerned with interaction between the physical and chemical characteristics of biodiesel with environmental factors, such as light, metal contamination, color changes, and sediment formation. Antioxidant concentration greatly influences engine performance and emission. The BSFC of biodiesel fuel with antioxidants is less than that of fuel without antioxidants. Moreover, an antioxidant can significantly reduce NOx formation during engine operation. Among the available synthetic antioxidants, only three antioxidants (TBHQ, PY, and PG) can significantly increase biodiesel stability. This article presents an overview of the stability of biodiesel, including the methods available for the prediction of its different stability properties. Feasible remedies to improve the stability of biodiesel and the effect of antioxidants in stabilized blends on engine performance and emission are also discussed.

With growing concern over greenhouse gases there is increasing emphasis on reducing CO2 emissions. Despite engine efficiency improvements plus increased dieselization of the fleet, increasing vehicle numbers results in increasing CO2 emissions. To reserve this trend the fuel source must be changed to renewable fuels which are CO2 neutral. As a renewable, sustainable and alternative fuel for compression ignition engines, biodiesel is widely accepted as comparable fuel to diesel in diesel engines. This is due to several factors like decreasing the dependence on imported petroleum, reducing global warming, increasing lubricity, and reducing substantially the exhaust emissions from diesel engine. However, there is a major disadvantage in the use of biodiesel as it has lower heating value, higher density and higher viscosity, higher fuel consumption and higher NOx emission, which limits its application. Here fuel additives become essential and indispensable tools not only to minimize these drawbacks but also generate specified products to meet the regional and international standards. Fuel additives can contribute towards fuel economy and emission reduction either directly or indirectly. Their use enable vehicle performance to be maintained at, or near, optimum over the lifetime of the vehicle. A variety of additives are used in automotive biodiesel fuel to meet specification limits and to enhance quality. For example, metal based additives, oxygenated additives, antioxidants, cetane number improvers, lubricity improvers and cold flow improvers are used to meet specifications and quality. This article is a literature review of the effect of various additives on biodiesel properties, engine performance and exhaust emission characteristics and the corresponding effect factors were surveyed and analyzed in detail. The review concludes that the use of additive in biodiesel fuel is inalienable both for improving properties and for better engine performance and emission control. Therefore, in order to find the appropriate fuel additives in the combustion applications, more experiments are needed to explore the different related mechanisms.

The energy crisis facing the world today is the result of the continuous depletion of fossil fuels caused by high usage demand. To alleviate the situation, researchers and scientists have been searching for low-cost, eco-friendly, and readily available substitutes to fossil fuel. Biodiesel can be a promising alternative source of energy. This study investigated the parameters of a direct-injection water-cooled diesel engine run with linseed biodiesel blends. These parameters include brake-specific fuel consumption (BSFC), brake thermal efficiency (BTE), and emission characteristics. Then, the performance of this engine was compared with that of a diesel fuel-run engine by evaluating the BSFC, BTE, and mechanical efficiency. Results show that the BSFC decreases as the load increases for all fuel blends and increases as the percentage of biodiesel in the blend increases; a 25.6% increase in BSFC is obtained at a low load. The BTE increases with increasing load; at a low load, the highest reduction in BTE is 15.38%. The CO emission reduces by approximately 5.49% at a low load for the B30 blend and 27.7% at a high load for the B20 blend compared with diesel. For pollution investigation, the emissions of NOX, HC, and CO were measured. The CO emission reduces by approximately 5.49% while HC and NOX emissions respectively increase by 15.8% and 19.5% at a low load.

Biodiesel is a renewable and sustainable alternative fossil fuel that is derived from vegetable oils and animal fats. This study investigates the production, characterization, and effect of biodiesel blends from two prominent feedstocks, namely, palm and coconut (PB30 and CB30), on engines. To aggregate the advantages of high ignition quality of palm and high oxygen content of coconut, combined blend of this two biodiesels (PB15CB15) is examined to evaluate its effect on engine performance and emission characteristics. Biodiesels are produced using the alkali catalyzed transesterification process. Various physicochemical properties are measured and compared with the ASTM D6751 standard. A 10 kW, horizontal, single-cylinder, four-stroke, and direct-injection diesel engine is employed under a full load and varying speed conditions. Biodiesel blends produce a low brake torque and high brake-specific fuel consumption (BSFC). However, all emissions, except for NOx, are significantly reduced. PB15CB15 improves brake torque and power output while reducing BSFC and NOx emissions when compared with CB30. Meanwhile, compared with PB30, PB15CB15 reduces CO and HC emissions while improving brake thermal efficiency. The experimental analysis reveals that the combined blend of palm and coconut oil shows superior performance and emission over individual coconut and palm biodiesel blends.

Now-a-days the demand of alternative fuel is continuously increasing all over the world due to the rapid depletion of fossil fuel and increased global demand. Biodiesel is renewable and sustainable energy source derived from vegetable oils and animal fats which can be the best substitute of fossil fuel. This paper investigates the property of different biodiesel such as palm, coconut and their blends with conventional diesel also analyzed the engine performance like engine break power, speed, break specific fuel consumption (BSFC), torque in diesel engine. In this paper 20% palm biodiesel with diesel (P20), 20% coconut biodiesel with diesel (C20), 30% palm biodiesel with diesel (P30), 30% coconut biodiesel with diesel (C30) and combination of 15% palm biodiesel and 15% of coconut biodiesel with diesel (C15P15) were used for study. Biodiesel was produced by using transesterification process. The density and kinematic viscosity for C15P15 fuel is slightly higher and flash point is slightly lower than diesel fuel as well as others two biodiesel blends whereas pure palm oil biodiesel shows the higher flash point and acid value. Engine performance test was carried out at 75 kg load condition with variable speeds of 1400 rpm to 2000 rpm at an interval of 200 rpm. Engine brake power produced by mixed biodiesel (C15P15) is slightly lower than the fossil diesel but slightly higher than biodiesel (only palm or coconut). Engine torque produce by the mixed biodiesel is almost the same with the fossil diesel but higher than the others biodiesel blends. Engine brake specific fuel consumption of mixed biodiesel is slightly higher than fossil diesel but lower than others existing biodiesel. It can be reported that the fuel C15P15 showed better performance and can be used as fuel alternative to diesel fuel to reduce the greenhouse gas emission and dependency on crude oil.

Internal combustion engine with its combustion chamber walls insulated by thermal barrier coating materials is referred to as low heat rejection engine or LHR engine. The main purpose of this concept is to reduce engine coolant heat losses, hence improve engine performance. Most of the researchers have reported that the thermal coating increases thermal efficiency, and reduces exhaust emissions. In contrast to the above expectations, a few researchers reported that almost there was no improvement in thermal efficiency. This manuscript investigates the contradictory results in order to find out the exact scenario. A wide range of coating materials has been studied in order to justify their feasibility of implementation in engine. The influence of coating material, thickness, and technique on engine performance and emissions has been studied critically to accelerate the LHR engine evolution. The objectives of higher thermal efficiency, improved fuel economy, and lower emissions are accomplishable but much more investigations with improved engine modification, and design are required to explore full potentiality of LHR engine.

Biodiesel having higher unsaturation possesses lower oxidation stability, which needs treatment of oxidation inhibitors or antioxidants. It is expected that antioxidants may affect the clean burning characteristic of biodiesel. Calophyllum inophyllum Linn oil is one of the promising non-edible based feedstock which consists of mostly unsaturated fatty acids. This paper presents an experimental investigation of the antioxidant addition effect on engine performance and emission characteristics. Biodiesel (CIBD) was produced by one step esterification using sulfuric acid (H2SO4) as catalyst and one step transesterification using potassium hydroxide (KOH) as a catalyst. Two monophenolic, 2(3)-tert-Butyl-4-methoxyphenol (BHA) and 2,6-di-tert-butyl-4-methylphenol (BHT) and one diphenolic, 2-tert-butylbenzene-1,4-diol (TBHQ) were added at 2000 ppm concentration to 20% CIBD (CIB20). The addition of antioxidants increased oxidation stability without causing any significant negative effect of physicochemical properties. TBHQ showed the greatest capability in increasing stability of CIB20. The tests were carried out using a 55 kW 2.5 L four-cylinder diesel engine at constant load varying speed condition. The performance results indicate that CIB20 showed 1.36% lower mean brake power (BP) and 4.90% higher mean brake specific fuel consumption (BSFC) compared to diesel. The addition of antioxidants increased BP and reduced BSFC slightly. Emission results show that CIB20 increased NOx but decreased CO and HC emission. Antioxidants reduced 1.6–3.6% NOx emission, but increased both CO and HC emission compared to CIB20. However, the level was below the diesel emission level. Thus CIB20 blends with antioxidants can be used in diesel engines without any modification.

Lubricants perform as anti-friction media. They facilitate smooth operations, maintain reliable machine functions, and reduce the risks of frequent failures. At present, the increasing prices of crude oil, the depletion of crude oil reserves in the world, and global concern in protecting the environment from pollution have renewed interest in developing and using environment-friendly lubricants derived from alternative sources. A biolubricant is renewable lubricants that is biodegradable, non-toxic, and emits net zero greenhouse gas. This study presents the potential of a biolubricant based on vegetable oil as an alternative lubricant according to studies published in highly rated journals in scientific indices. In the first part of this paper, the source, properties, as well as advantages and disadvantages of the biolubricant are discussed. The second part describes the potential of vegetable oil-based biolubricants as alternative lubricants for automobile applications. The final part describes the world biolubricant market and its future prospects. Biolubricants are potential alternative lubricants because of their low toxicity, good lubricating properties, high viscosity index, high ignition temperature, increased equipment service life, high load-carrying abilities, good anti-wear characteristic, excellent coefficient of friction, natural multi-grade properties, low evaporation rates, and low emissions into the atmosphere.

Energy demand is increasing dramatically because of the fast industrial development, rising population, expanding urbanization, and economic growth in the world. To fulfill this energy demand, a large amount of fuel is widely used from different fossil resources. Burning of fossil fuels has caused serious detrimental environmental consequences. The application of biodiesel has shown a positive impact in resolving these issues. Edible vegetable oils are one of the potential feedstocks for biodiesel production. However, as the use of edible oils will jeopardize food supplies and biodiversity, non-edible vegetable oils, also known as second-generation feedstocks, are considered potential substitutes of edible food crops for biodiesel production. This paper introduces some species of non-edible vegetables whose oils are potential sources of biodiesel. These species are Pongamia pinnata (karanja), Calophyllum inophyllum (Polanga), Maduca indica (mahua), Hevea brasiliensis (rubber seed), Cotton seed, Simmondsia chinesnsis (Jojoba), Nicotianna tabacum (tobacco), Azadirachta indica (Neem), Linum usitatissimum (Linseed) and Jatropha curcas (Jatropha). Various aspects of non-edible feedstocks, such as biology, distribution, and chemistry, the biodiesel’s physicochemical properties, and its effect on engine performance and emission, are reviewed based on published articles. From the review, fuel properties are found to considerably vary depending on feedstocks. Analysis of the performance results revealed that most of the biodiesel generally give higher brake thermal efficiency and lower brake-specific fuel consumption. Emission results showed that in most cases, NOx emission is increased, and HC, CO, and PM emissions are decreases. It was reported that a diesel engine could be successfully run and could give excellent performance and the study revealed the most effective regulated emissions on the application of karanja, mahua, rubber seed, and tobacco biodiesel and their blends as fuel in a CI engine.

The increase of energy demand coped with utilization of fossil resources have engendered serious environmental impact. The progressively stringent worldwide emission legislation and increasing greenhouse gas emission require significant research effort on alternative fuels. Therefore, biodiesels are becoming important increasingly due to its ease in adaptation, environmental benefits and prospect in energy security. Biodiesel derived from vegetable oils, waste cooking oils and animal fats are long chain fatty acid alkyl esters, which contains unsaturated portions that are susceptible to oxidation. Biodiesel oxidation is a complex process having a number of mechanisms involved. Autoxidation radical chain reactions are the primary cause of biodiesel degradation that leads to formation of hydroperoxide, which, after that decompose to form an array of secondary oxidation products like aldehydes, ketones, carboxylic acids, oligomers, gum, sediment etc. Antioxidants are often used to inhibit biodiesel oxidative degradation. The present review attempts to cover the inhibition action of natural and synthetic antioxidants, methods used to analyze biodiesel oxidation and their effect on biodiesel derived from various feedstocks. Phenolic antioxidants are more effective compared to amine antioxidants. Pyrogallol is found to be the most effective antioxidant to improve the oxidation stability in case of almost all biodiesels reviewed.

Biodiesel can be described as a safe alternative fuel, which can replace petroleum diesel in the future. It consists of long-chain fatty acid methyl esters (FAME). Biodiesel has high lubricity and is a clean burning fuel. It also produces less air pollution, is renewable biodegradable, and is safer for the environment. Since biodiesel is produced from vegetable oil, animal fats, used cooking oil, and so forth, which may contain more or less unsaturated fatty acids that are prone to oxidation accelerated by exposure to air during storage and at high temperature, it may yield polymerized compounds. The oxidation and thermal stability of the fuel changes with storage time due to the formation of oxidation. Therefore, the aim of this study to evaluate the stabilities of biodiesel according to measured fuel properties, such as density, viscosity, flash point, total acid number (TAN), and total base number (TBN), by using various methodologies. In addition, oxidation stability of the samples was measured by the induction period using a Rancimat instrument. In this experiment, palm oil methyl ester (PME), palm biodiesel blend (40% PME and 60% diesel fuel), jatropha methyl ester (JME), jatropha biodiesel blend (40% JME and 60% diesel fuel), coconut oil methyl ester (COME), and conventional diesel fuel were used. Experiments were carried out at intervals over a 12-week test period. The experimental results for JME and PME showed similar performance in terms of flash point. All samples met the standard specification of the American Society for Testing and Materials (ASTM) D6751. (3 h) regarding the induction period, except for JME and its biodiesel blend, which did not meet the EN 14214 (6 h) standard specification. Among the fuel samples giving the worst results for TBN value due to oxidation, overall, among the biodiesels, PME and COME were found to give better results with respect to oxidation and storage stabilities.

The purpose of this study is to investigate the effect of jatropha oil doped with lube oil on tribological characteristics of IP 239 standard using four ball tribotester. The ball test material was EN31 steel, 12.7mm in diameter with a surface finish of 0.1 micrometer center lime average (CLA). The test was performed at temperature of 750c with different loads (15kg and 40kg) where rotating speed was 1500rpm and test duration of 3600s. The lube oil used for this experiment was SAE 40 and contaminated with a various blends like 1%, 2%, 3%, 4%, 5%, of jatropha oil. The lubricants were characterized by viscosity using viscometer. From the experimental result, it is found that wear scar diameter is increased with the increase of load for lube oil and reduced by addition of percentage of jatropha oil. Friction torque analyzed in this experiment and J5 shows dominant performance at 40kg load. Flash temperature parameter also studied in this experiment and results shown that 5% adding jatropha oil has the less possibility to film breakdown. The overall results of this experiment reveal that the addition of 5% jatropha oil with base lubricant shows better performance and anti-wear characteristics. This blend can be used as lubricant oil which is environment friendly in nature and would help to reduce petroleum based lubricant substantially.

The purpose of this work is to test the feasibility of biodiesel as a substitute for diesel used in a direct injection (DI) diesel engine. The biodiesel was produced by an esterification and transesterification process. Experiments were conducted with diesel–biodiesel blends containing 10 and 20% biodiesel with the diesel fuel. The results of the biodiesel blends are compared with baseline diesel which was assessed at constant speed in a single cylinder diesel engine at various loading conditions. The physicochemical properties of palm and Calophyllum inophyllum biodiesel and their blends meet the standard specification ASTM D6751 and EN 14214 standards. The maximum brake thermal efficiency was attained with diesel fuel, 10% palm biodiesel (PB10) and 10% C. inophyllum biodiesel (CI10) at all load condition except low load condition. Engine emission results showed that the 20% C. inophyllum with 80% diesel blend exhibited 6.35% lower amount of brake specific carbon monoxide, and the PB20 blend and CI20 blend reduced brake specific hydrocarbon emission by 7.93 and 9.5%, respectively. NOx emission from palm and C.inophyllum biodiesel blends are found to be 0.29–4.84% higher than diesel fuel. The lowest smoke intensity is found at 27.5% for PB10 and CI10 biodiesel blends compared with diesel fuel.