10 research outputs found
Experimental Investigations of Oxidation Stability of Biodiesel Produced from Manketti Seeds Oil (Schinziophyton rautanenii)
This research article published by ACS Publications, 2011In this study, biodiesel from Manketti seeds oil (Schinziophyton rautanenii) was investigated to determine its suitability for use as a petrodiesel substitute. The fuel-related properties of Manketti oil methyl ester (MOME) were determined and compared to global biodiesel standards. Most of the determined fuel properties of MOME fulfilled the minimum requirements of ASTM D6751 and EN 14214 biodiesel standards. However, MOME did not meet EN 14214 oxidation stability requirements (6 h). The stability of biodiesel is very critical, and biodiesel requires antioxidants to meet storage requirements and to ensure fuel quality at all points along the distribution chain. This study evaluated the effectiveness of three antioxidants: 1,2,3-trihydroxybenzene (pyrogallol, PY), 3,4,5-trihydroxybenzoic acid (propyl gallate, PG), and 2-tert-butyl-4-methoxyphenol (butylated hydroxyanisole, BHA) on the oxidation stability of MOME. The result showed that the effectiveness of these antioxidants was in the order of PY > PG > BHA. Overall, the biodiesel derived from Manketti seeds oil can be used as partial substitute for mineral diesel
Normal Butanol Additive in Methanol-Gasoline Blends Fired in a Spark Ignition Single Cylinder Engine : Effects on Combustion and Emission Characteristics
The effect of firing n-butanol additives in methanol-gasoline blends is compared with that of methanol-gasoline blends of total alcohol volume of 10 to 90 % in gasoline fuel (GF). The comparison was based on combustion and regulated remission characteristics. Tests were carried out on a BASF octane rating engine. Higher volatility and lower energy content of methanol-gasoline blends used were improved by the addition of n-butanol to the blends. Additives of n-butanol was recommended for the shortening combustion duration; reducing engine-out oxygen a benefit for downsizing the intake manifold and raising the heating value of fuel mixture.Добавление дозированной спиртовой добавки, которая используется в стандартных бензиновых топливах, ограничивается в связи с пониженной энергией (теплотой сгорания) спирта, однако энергия топлива возрастает при использовании в метанол-бензиновой смеси, помимо имеющейся, другой спиртовой добавки — н-бутанола. При этом благодаря пониженной летучести н-бутанола ослабляются проблемы с топливной системой двигателя, обусловленные повышенной летучестью метанол-бензиновых смесей. Цель работы состояла в определении преимуществ использования двойных спиртовых смесей с бензином (DAG) по сравнению с односпиртовыми смесями (SAG). Содержание спиртов в смеси превышало 30 % (об.). Воздействие горючих спиртовых добавок н-бутанола к метанол-бензиновым смесям (DAG) сравнивается с таковым при использовании метанол-бензиновых смесей (SAG) для случаев содержания спиртов от 10 до 90 % (об.) в бензиновом топливе. Сравнение основывалось на характеристиках горения по степени приближения к регламентируемым показателям вредных выбросов: NOx, CO, UHC (несгоревшие углеводороды). Испытания проводились на двигателе фирмы BASF с пересчетом мощности (по октану). Установлено, что выбросы UHC сокращались в большей степени при работе с SAG, чем при использовании DAG. Повышение доли спирта в бензиновом топливе сопровождается незначительным уменьшением выбросов NOx. При этом выбросы UHC для смесей минимальны, когда содержание NOx максимально, и наоборот. Установлено, что рост NOx ® (NOx)max при высоких температурах сопровождается минимизацией выбросов СО и UHC. Рекомендуется добавление н-бутанола для сокращения продолжительности горения и снижения содержания кислорода на выходе из двигателя как основа сокращения габаритов впускного (всасывающего) трубопровода и повышения теплоты сгорания топливной смеси.Додавання нормального бутанола до метанол-бензиновым сумішей, що спалюються в одноциліндровому двигуні з іскровим запаленням : Вплив на характеристики горіння та утворення шкідливих речовин Додавання дозованої спиртової домішки, яка використовується у стандартних бензинових паливах, обмежується у зв’язку зі зниженою енергією (теплотою згоряння) спирту, проте енергія палива зростає при використанні у метанол-бензиновій суміші, окрім тієї, що є, іншої спиртової домішки — н-бутанола. При цьому завдяки зниженій летючості н-бутанола ослаблюються проблеми з паливною системою двигуна, зумовлені підвищеною летючістю метанол-бензинових сумішей. Мета роботи полягала у визначенні переваг використання подвійних спиртових сумішей з бензином (DAG) у порівнянні з односпиртовими сумішами (SAG). Вміст спиртів у суміші перевищував 30 % (об.). Дія горючих спиртових домішок н-бутанола до метанол-бензинових сумішей (DAG) порівнюється з такою при використанні метанол-бензинових сумішей (SAG) для випадків вмісту спиртів від 10 до 90 % (об.) у бензиновому паливі. Порівняння грунтувалося на характеристиках горіння за мірою наближення до регламентованих показників шкідливих викидів: NOx, CO, UHC (незгорілі вуглеводні). Випробування проводилися на двигуні фірми BASF з перерахунком потужності (за октаном). Встановлено, що викиди UHC скорочувалися більшою мірою при роботі з SAG, ніж при використанні DAG. Підвищення долі спирту у бензиновому паливі су-проводжується незначним зменшенням викидів NOx. При цьому викиди UHC для сумішей мінімальні, коли вміст NOx максимальний, та навпаки. Встановлено, що зростання NOx → (NOx)max при високих температурах супроводжується мінімізацією викидів СО та UHC. Рекомендовано додавання н-бутанола для скорочення тривалості горіння та зниження вмісту кисню на виході з двигуна як основа скорочення габаритів впускного (всмоктуючого) трубопроводу та підвищення теплоти згоряння паливної суміші
Combustion and Emission Characteristics of Blends: -n-Butanol- Diesel (D2); and Dual Alcohols: n-Butanol-Methanol with Gasoline in Internal Combustion Engines
A study of the effects of oxygenated alcohol/gasoline/diesel fuel blends on performance, combustion, and emission characteristics in conventional reciprocating engines is reported. On the one hand, in alcohol-gasoline blends, dual alcohols-gasoline blends have not yet been sufficiently proven as suitable alternatives to single alcohol-gasoline blends in engines as far as performance is concerned. On the other hand, n-butanol-diesel, although it has a better miscibility factor in diesel than methanol or ethanol, is limited with regard to extensive application in the diesel engines due to its low cetane number. Engine performance was compared using single alcohol-gasoline and dual alcohol-gasoline blends, where the dual blends were constrained to meet the vapor issues regarding fuels and regulations. The blends were selected in terms of a combination by volume of one being higher alcohol (n-butanol) and the other, lower alcohol (methanol). The engines used for this study included a single-cylinder and a four-cylinder, naturally aspirated, four-stroke spark ignition engines and a four-cylinder, four-stroke compression ignition turbocharged diesel engine. In the n-butanol-diesel studies, a comparison was made with other studies in order to determine how suitable n-butanol-diesel blends were across the biofuel family such as the biodiesel-ethanol-diesel blends. The findings were as follows: The dual alcohols-gasoline blends performed better than the single alcohol-gasoline blends depending on certain compositional ratios of the alcohols in gasoline regardless of vapor pressure consideration. The n-butanol/diesel alcohol blend (B5, B10, and B20, where B5 represents 5% n-butanol and 95% diesel) significantly reduced the regulated emissions in a turbocharged engine compared to other studies using biodiesel-diesel blends. The significant decrease in NOx, CO emissions, and reduction of unburned hydrocarbons content using n-butanol/diesel fuel (DF) blends were found experimentally. The use of dual alcohol /gasoline blends was beneficial due to their shorter combustion duration in crank angles and their higher-energy content compared with single alcohol-gasoline blends. The n-butanol/diesel blend fired in the diesel engine showed a higher brake thermal efficiency and improved brake specific fuel consumption compared to the study by others where ethanoldiesel and methanoldiesel blends were used
Engine performance, exhaust emissions and combustion characteristics of a CI engine fuelled with croton megalocarpus methyl ester with antioxidant
This research article published by Elsevier Ltd., 2011The use of biodiesel as a substitute for petroleum-based diesel has become of great interest for the reasons of combating the destruction of the environment, the price of petroleum-based diesel and dependency on foreign energy sources. But for practical feasibility of biodiesel, antioxidants are added to increase the oxidation stability during long term storage. It is quite possible that these additives may affect the clean burning characteristics of biodiesel. This study investigated the experimental effects of antioxidants on the oxidation stability, engine performance, exhaust emissions and combustion characteristics of a four cylinder turbocharged direct injection (TDI) diesel engine fuelled with biodiesel from croton megalocarpus oil. The three synthetic antioxidants evaluated its effectiveness on oxidation stability of croton oil methyl ester (COME) were 1, 2, 3 tri-hydroxy benzene (Pyrogallol, PY), 3, 4, 5-tri hydroxy benzoic acid (Propyl Gallate, PG) and 2-tert butyl-4-methoxy phenol (Butylated Hydroxyanisole, BHA). The fuel sample tested in TDI diesel engine include pure croton biodiesel (B100), croton biodiesel dosed with 1000 ppm of an effective antioxidant (B100 + PY1000), B20 (20% croton biodiesel and 80% mineral diesel) and diesel fuel which was used as base fuel. The result showed that the effectiveness of the antioxidants was in the order of PY > PG > BHA. The brake specific fuel consumption (BSFC) of biodiesel fuel with antioxidants decreased more than that of biodiesel fuel without antioxidants, but both were higher than that of diesel. Antioxidants had few effects on the exhaust emissions of a diesel engine running on biodiesel. Combustion characteristics in diesel engine were not influenced by the addition of antioxidants in biodiesel fuel. This study recommends PY and PG to be used for safeguarding biodiesel fuel from the effects of autoxidation during storage. Overall, the biodiesel derived from croton megalocarpus oil can be utilized as partial substitute for mineral diesel
Evaluation of the Oxidation Stability of Biodiesel Produced from Moringa oleifera Oil
This research article published by ACS Publications, 2011Biodiesel is considered as an alternative fuel to petroleum-based conventional diesel fuel. Dependent upon the raw material, biodiesel can contain more or less unsaturated fatty acids in its composition, which are susceptible to oxidation reactions accelerated by exposure to oxygen and high temperatures. The present study evaluated the oxidative stability of biodiesel produced by methanolysis of Moringa oleifera oil, primarily available on the African continent. The evaluation was conducted by means of the Rancimat instrument, at a temperature of 110 °C, with an air flow of 10 L/h. Moringa oil methyl ester (MOME) displayed an oxidation stability of 5.05 h. Thus, MOME met the oxidative stability requirement in the American Society for Testing and Materials (ASTM) D6751 standard, which prescribes a minimum of 3 h, but did not meet the minimum requirement prescribed in the EN 14214 standard, which is 6 h. Also, this study evaluated the effectiveness of four antioxidants, 1,2,3-trihydroxybenzene [pyrogallol (PY)], 3,4,5-trihydroxybenzoic acid [propyl gallate (PG)], 2-tert-butyl-4-methoxyphenol [butylated hydroxyanisole (BHA)], and 2,6-di-tert-butyl-4-methylphenol [butylated hydroxytoluene (BHT)], on the oxidation stability of MOME. The result showed that the effectiveness of these antioxidants was in the order of PY > PG > BHA > BHT
Impact of Antioxidant Additives on the Engine Performance and Exhaust Emissions Using Biodiesel made from Jatropha Oil of Eastern Africa Origin
This research article published by the Journal of the South African Institution of Mechanical Engineering, 2016Biodiesel’s chemical nature makes it more susceptible to
oxidation in comparison to mineral diesel. Biodiesels are
doped with antioxidants to increase oxidation stability for
long term storage. However, it is quite possible that these
additives may affect fuel related properties of biodiesel
such as cetane number and kinematic viscosity and also
the performance of engine and exhaust emissions.
Therefore, this study investigated the effects of antioxidant
on the oxidation stability, cetane number and kinetic
viscosity of biodiesel made from jatropha oil of Eastern
Africa origin. Also, the influence on the performance and
exhaust emissions of a four cylinder turbocharged direct
injection (TDI) diesel engine. Antioxidant 1, 2, 3 trihydroxy benzene (Pyrogallol, PY), as the most effective
antioxidant based on the earlier work of the authors was
mixed with the produced Jatropha Oil Methyl Ester
(JOME) at different concentrations to improve the
oxidation stability. The results showed that, the oxidation
stability of JOME increased with the increase of PY
dosage. Also, cetane number slightly increased with
additional of antioxidant whereas kinetic viscosity was
observed to decrease with PY dosage. The brake specific
fuel consumption (BSFC) of JOME with antioxidants
decreased more than that without antioxidants, but both
were higher than that of diesel and diesel/biodiesel blends.
No significant effects were observed on the exhaust
emissions of a diesel engine running on biodiesel (JOME)
dosed with antioxidant PY
n-Butanol-Diesel (D2) Blend Fired in a Turbo-Charged Compression Ignition Engine: Performance and Combustion Characteristics
The use of biofuels that include n-butanol in diesel fuel (DF) is attracting attention in the search for the reduction of emissions into the environment due to the burning of fossil fuel. The performance and combustion characteristics were evaluated in this study using blends B5, B10, and B20 (B5: 5% n-butanol and 95% DF) in a turbo-charged direct injection compression ignition engine. In the n-butanol diesel studies, a comparison was made with other studies that also included biodiesel in order to determine how suitable n-butanol-diesel blends were to use in internal combustion engines. Combustion characteristics of B20 (n-butanol 20% and 80% DF) improved when the study was compared with a similar study that included 40% biodiesel added to B20. A higher value of the standard deviation for DF than the blends was observed from the standard deviation diagram, indicating a more stable combustion process for the blends than DF. Soot reduction relative to DF at 1500 rpm at 75% load for B05, B10, and B20 mixtures was 55.5, 77.8, and 85.1%, respectively. This reduction is a significant advantage of blending DF with smaller shared volumes of bioalcohol
Impact of antioxidant additives on the oxidation stability of biodiesel produced from Croton Megalocarpus oil
This research article published by Elsevier Ltd., 2011The increase in crude petroleum prices, limited resources of fossil fuels and environmental concerns have led to the search of alternative fuels, which promise a harmonious correlation with sustainable development, energy conservation, efficiency and environmental preservation. Biodiesel is well positioned to replace petroleum-based diesel. Biodiesel is a non-toxic, biodegradable and renewable biofuel. But the outstanding technical problem with biodiesel is that, it is more susceptible to oxidation owing to its exposure to oxygen present in the air and high temperature. This happens mainly due to the presence of varying numbers of double bonds in the free fatty acid molecules. This study evaluates oxidation stability of biodiesel produced from Croton megalocarpus oil. Thermal and Oxidation stability of Croton Oil Methyl Ester (COME) were determined by Rancimat and Thermogravimetry Analysis methods respectively. It was found that oxidation stability of COME did not meet the specifications of EN 14214 (6 h). This study also investigated the effectiveness of three antioxidants: 1,2,3 tri-hydroxy benzene (Pyrogallol, PY), 3,4,5-tri hydroxy benzoic acid (Propyl Gallate, PG) and 2-tert butyl-4-methoxy phenol (Butylated Hydroxyanisole, BHA) on oxidation stability of COME. The result showed that the effectiveness of these antioxidants was in the order of PY > PG > BHA