Usage In Engines Research Articles

Gasification and Techno-Economic Study of Palm Shell Biomass and the Utilization of Dual Fuel Diesel Engine Operated Diesel Engine

Indonesia's oil reserves and production are steadily declining, accompanied by increasing fossil fuel consumption, particularly in Diesel Power Plants, which contribute to environmental impacts and exacerbate global warming. In response, the government issued a policy in 2028 to implement carbon emission trading for Diesel Power Plants with a capacity below 2 MW, as part of Indonesia's commitment to achieving Net Zero Emission (NZE) by 2060. Considering the significant state assets in the form of diesel-powered generators (approximately 5,200 diesel power plants) still operating throughout Indonesia, the government has also issued policies and strategic plans to develop Biomass Power Plants. This research focuses on examining the combination of biosolar B35 and syngas usage in diesel engines, known as dual fuel engine technology, utilizing abundant palm shell biomass waste in Southeast Sulawesi. The gasification process to create syngas uses a multi-stage downdraft gasifier system with the optimal air ratio variation from previous research, namely 1:7:2 in the pyrolysis, oxidation, and reduction zones. Testing is conducted on a diesel engine at 3000 rpm with load variations ranging from 500 Watt to 4500 Watt. The load is gradually increased at 500-Watt intervals. The syngas mass flow rate is also varied by adjusting four different syngas valve openings to the diesel engine's intake manifold. This study will compare the results of diesel engine operation using single fuel (biosolar B35) with dual fuel (biosolar B35 + syngas) at each engine load interval to determine engine performance, biosolar B35 fuel substitution or savings, carbon reduction in the dual fuel diesel system, and calculate the techno-economics for up-scaling on a 250 kW capacity engine at PT Nusantara Power, Unit Pembangkitan Kendari, ULPLTD Kolaka, Southeast Sulawesi. The aim is to support government programs and policies in realizing environmentally friendly and sustainable Diesel Power Plants, as well as to open opportunities for developing biomass-based dual fuel engine technology in Indonesia.

Characteristics and evolution of bioethanol from Manila Tamarind (Pithecellobium dulce) leaf through fermentation

<p>This study's two primary goals are to synthesize bioethanol from biowaste and examine its thermal characteristics. Bioethanol must first undergo a comprehensive assessment of its thermal characteristics in order to be approved for usage in spark-ignition engines. A multi-step procedure comprising extraction, pretreatment, enzymatic hydrolysis, and fermentation was used to manufacture the bioethanol. The raw material was put through a preliminary screening using thermogravimetric analysis to find the mass loss rate as a function of temperature before to starting this process. Remarkably, the Manila tamarind leaves exhibited the highest mass loss, up to 34%. Enzymatic cellulose conversion to fermentable sugars was a critical step in the production of cellulosic ethanol. Following hydrolysis, Saccharomyces cerevisiae was employed in the fermentation process, leading to the bioethanol synthesis phase. The Manila Tamarind leaves yielded the most, around 29% by weight, which is amazing. In order to assess the thermal properties of the extracted ethanol, a variety of parameters were carefully examined, including the viscosity, density, cetane number, and calorific value. In each of these areas, mixtures of tire oil, gasoline, and bioethanol consistently outperformed the others. Furthermore, Fourier Transform Infrared Spectrometry spectra were utilized to validate the concentrations of potential groups, including alcohol, aromatic, alkyne, amide, and carbonyl groups. Clear objectives guide the fermentation process, aiming for consistent quality, safety, and functionality in the end product.</p>

Comparative analysis of waste tire pyrolysis oil and gasoline as low reactivity fuel in RCCI engine

ABSTRACT The utilization of alternative fuels in internal combustion engines has gained significant attention due to concerns about energy security and environmental sustainability. Waste tire pyrolysis oil (WTPO) is a potential alternative fuel that can be produced from waste vehicle tires through a pyrolysis process. In this study, the possible use of WTPO in a diesel engine operating under Reactivity Controlled Compression Ignition (RCCI) mode was investigated. In the study, the use of WTPO as a low-reactivity fuel in RCCI engines is examined, highlighting the importance of innovative approaches to alternative fuels with varying reactivity levels for effective combustion control and emission reduction. In the experimental work, WTPO was tested at different energy rates of 15%, 30%, and 45% into the intake port using the PFI system, while conventional diesel fuel was injected directly into the cylinder by the CRDI system. The tests were carried out under different engine load conditions while maintaining a constant engine speed of 2400 rpm. The performance, combustion, and emission characteristics of the engine were analyzed and compared between WTPO and conventional gasoline fuel as LRF. The study results show that using WTPO in RCCI operation with sustainable ringing intensity leads to significant increases in Brake Thermal Efficiency (BTE) compared to gasoline usage, with BTE increments of up to 5%, 3.3%, and 6.3% observed with increasing engine load. Furthermore, WTPO usage in RCCI engines effectively reduced hydrocarbon (HC) emissions, addressing a significant issue, and maintaining the known benefits of reactivity-controlled combustion. These findings suggest that WTPO can be utilized as a viable low-reactivity fuel in RCCI engines with acceptable performance, combustion, and emission characteristics.

Comprehensive techno-economic assessment of power technologies and synthetic fuels under discussion for ship applications

The decarbonization of the global ship traffic is one of the industry’s greatest challenges for the next decades and will likely only be achieved with the introduction of synthetic fuels. Until now, however, not one single best technology solution emerged to ideally fit this task. Instead, different energy carriers including hydrogen, ammonia, methanol, methane, and synthetic diesel are subject of discussion for usage in either internal combustion engines or fuel cells. In order to drive the selection procedure, a case study for the year 2030 with all eligible combinations of power technologies and fuels is conducted. The assessment quantifies the technologies’ economic performances for cost-optimized system designs and in dependence of a ship’s mission characteristics. Thereby, the influence of trends for electrofuel prices and shipboard volume opportunity costs are examined.Even if gaseous hydrogen is often considered not suitable for large ship applications due to its low volumetric energy density, both the comparatively small fuel price and the high efficiency of fuel cells lead to the overall smallest system costs for passages up to 21 days, depending on assumed cost parameters. Only for missions longer than seven days, fuel cells operating on methanol or ammonia can compete with gaseous hydrogen economically.

Hydrogen-enriched palm biodiesel as a potential alternative fuel for diesel engines: Investigating performance and emission characteristics and mitigation strategies for air pollutants

Palm biodiesel is one of the most suitable alternative fuels due to its capability to replace traditional fossil fuel usage in IC engines. Even as palm biodiesel (POBD) reduces harmful pollutant gases, the engine performance is not on an equal scale with neat diesel. To address this shortcoming, an investigation was carried out to examine the application of palm biodiesel (PBD) and hydrogen induction through the intake air at the flow rates of 6 and 8LPM (Litre Per Minute) in the compression ignition (CI) engine. The experimental study shows that POBD has poor engine performance and moderate pollution reduction compared with neat diesel. When compared to POBD and neat diesel, the higher calorific value and other H2 characteristics improve combustion properties, resulting in higher engine performance and lower pollutant gases (except NOx). When compared to the palm biodiesel blend (BD 30), the results of BD30+8LPM reduced the Specific fuel consumption (SFC) by 0.0885kg/kWh and improved the brake thermal efficiency (BTE) by 6.67%. The Carbon monoxide (CO), hydro carbon (HC), and smoke opacity were reduced by 0.047% volume, 29.2 ppm, and 6.52% respectively. A marginal increase in NOx was seen as 297.6 ppm.

An experimental and kinetic modeling study on the high-temperature ignition and pyrolysis characteristics of cyclohexylamine

Amine compounds are an important class of nitro-containing fuels and represent as promising renewable fuels. However, the structural effect from the alkyl group on the combustion characteristics of amines remains an urgent problem to promote their usage in practical engines. To probe and replenish the combustion properties of amine fuels, this work reported an experimental and kinetic modeling study on the high-temperature ignition and pyrolysis characteristics of cyclohexylamine over a wide range of conditions. Specifically, a high-pressure shock tube is used to measure the ignition delay times under the temperature range from 1100 K to 1700 K with pressure of 2 and 5 bar and the equivalence ratios of 0.5, 1.0 and 2.0. The pyrolysis characteristics is studied using a single-pulse shock tube at fuel concentration of 0.5% diluted by argon in the temperature range 950–1400 K at 5 and 10 bar with the residence time around 1.6 microsecond. A detailed kinetic mechanism is developed to simulate the experimental results. To improve the accuracy of the detailed mechanism, primary initial reactions of cyclohexylamine including the hydrogen abstraction reactions and the CN decomposition reaction are theoretically studied at G4//M06–2X/6–311++G(d, p) level of theory with transition state theory and RRKM/mater equation. The detailed kinetic mechanism shows good prediction accuracy of the ignition delay times and pyrolysis product distributions under different temperature, pressure and equivalence ratio conditions. Sensitivity analysis results indicate that the most sensitive reaction is O2 + H = O + OH with the most negative sensitivity coefficient and the abstraction reaction of vinylamine with OH radical, C2H3NH2 + OH = C2H3NH + H2O also exhibits large sensitivity coefficients. Reaction path analysis reveals that the abstraction reactions control the initial oxidation of cyclohexylamine and cyclohexen-1-amine, cyclohexen-2-amine, and cyclohexen-3-amine are also major intermediates during the oxidation of cyclohexylamine besides small pyrolysis products.

Performance of Dual-fuel (DF) Engine Powered with the Producer Gas Derived From Sugar Cane Bagasse and Diesel Injection

Renewable and sustainable fuel usage in diesel engines ensures energy security and overseas exchange savings besides conveying both socioeconomic and environmental concerns. This research presents experimental work that has been done on single-cylinder, 4-stroke, diesel engine of direct injection run in DF mode using PG derived from sugar cane bagasse renewable and sustainable fuels. A 45° gas venture is designed and developed to provide a stoichiometric mixture of gas and air entry into the intake manifold of the DF engine during suction stroke. A compressed mixture of air and gas is ignited by injecting diesel into the engine cylinder at 205 bar pressure and at different timings of injection. The effect of timing of injection on the DF engine performance is studied by varying it from 23 to 31obtdc in steps of 4obtdc. Experimental investigation showed that 27oBTC resulted in improved BTE with reduced emissions of hydrocarbon, smoke, and CO while NOx, peak pressure increased. It is noticed that the operation of producer gas lowers the power derating by 20% and the DF engine could run up to 80% load with increased nitric oxide (NOx) emissions. The developed DF engine worked satisfactorily with acceptable performance and emission norms and assisted in partially substituting the fossil diesel fuel with a substitution of 60-70% by the PG operation.

Hydrothermal liquefaction of sewage sludge into biocrude: Effect of aqueous phase recycling on energy recovery and pollution mitigation

Hydrothermal liquefaction (HTL) of sewage sludge is facing the challenges of low biocrude yield, a large number of intractable aqueous phase and heavy metals pollution. In this study, the aqueous phase produced by HTL was recycled as solvent with an aim to improve the biocrude yield and mitigate potential pollution. Results showed that the recycling of aqueous phase increased the biocrude yield from 17.9 to 30.5% and the energy recovery ratio from 40.3 to 61.7%. The recycling could increase the contents of Zn, Cu, Pb and Cr in solid residues by 2.7−3.0 times. It is worth emphasizing that the recycling reduced the COD of aqueous phase by 24.9%. However, the enhanced protein hydrolysis process reduced the calorific value of biocrude from 36.4 to 28.5 MJ/kg, and promoted the migration of the nitrogen to the aqueous phase, which was not environmentally favourable for the direct usage in diesel engines. Analysis showed that the ketones and the phenols in aqueous phase participated in HTL process as reactants, and the acids promoted the hydrolysis of protein in the sludge. Overall, the recycling of aqueous phase effectively improved the energy recovery and alleviated pollution of the sludge HTL.

A Review of the Effects of Biodiesel and Ethanol on Performance and Emission Characteristics of Diesel Engines

The effect of engine emissions due to using fossil fuels and its management is one of concerns cross the world. Recently, biodiesel and ethanol are well recognized as appropriate alternatives for diesel engines. In various countries bioethanol and biodiesel have attracted great attentions as alternative fuels in application and research because of renewability and environmentally friendly properties and reduction of using fossil resources. Here the benefits and limitations of usage the biofuels in diesel engine were reviewed. The effects of biodiesel-diesel, ethanol-diesel, and biodiesel-ethanol diesel blends on diesel engine were reviewed. Biodiesel and bioethanol are used in diesel engines mainly due to lower exhaust emissions and hence less environmental pollutions. As biodiesel and ethanol usage in diesel engines are some limitations, the optimization of biofuels components in the fuel blends of diesel engines is necessary. So, optimization of using biofuels in diesel engines as well as using new additives and analytical approaches was recommended in future studies.

Tribotests of Valve Seats Made of ADI and Q - Cryo Cast Iron with Spheroidal Graphite

In this paper, microstructural and tribological properties of valve seats made of ADI and Q – cryo cast iron with spheroidal graphite have been investigated in comparison to stellite 6. The studies have shown that the cheaper variant of cast iron thermally threated can have comparable properties suitable for valve seats usage in gas combustion engines. In the work the tribological test was performed and resulted into the course of friction coefficient of the tested samples and selected properties as the thickens of the valve seat or hardness and Young modulus after cast iron thermal treatment were measured.

Impact of adding EDA in Jatropha and Waste cooking oil biodiesel on NOx reduction in diesel engine emission

ABSTRACT Biodiesel usage in diesel engines is generally accepted as comparable fuel. To improve the quality of biodiesel, several fuel additives are used. In the present research, ethylenediamine (EDA) was used as an additive in Jatropha curcas biodiesel (JCB) and Waste cooking oil biodiesel (WCB) to reduce the nitrogen oxides (NOx) emission. Different blends of JCB and WCB with diesel have been prepared with and without EDA and tested on a vertical, 4-stroke, single-cylinder diesel engine. Results showed that by using 0.02% (by weight) EDA additive in WCB10 and JCB10 blends, NOx and carbon dioxide emissions were reduced by nearly 5% and 1.5% respectively. However, small rise in carbon mono-oxide (∼1%), unburnt hydrocarbon (∼0.7%), brake specific fuel consumption (∼0.26%) and a slight reduction in brake thermal efficiency (∼0.5%) were observed. The blends WCB10 and JCB10 with 0.02% EDA additive could be alternative fuels for diesel engines without modifying the existing engine.

Experimental evaluation over the effects of natural antioxidants on oxidation stability of binary biodiesel blend

Prolonged storage of biodiesel leads to deterioration of fuel properties and its usage in engines results in drop-in performance characteristics. The present study deals with the effect of natural antioxidants on the storage stability of binary biodiesel blend of Jatropha biodiesel and lemongrass oil, which are synthesized through transesterification and steam distillation process, respectively. Natural antioxidants such as sesame, horse gram, sweet basil, coffee, and peas were employed in the current study. Thermal analysis of the antioxidants was carried out utilizing differential scanning calorimetry and thermogravimetric analysis to study the effect of temperature on antioxidants. Ethanol extract of natural antioxidants was prepared at various concentrations such as 500, 1000, and 1500 ppm. Total phenol content in the antioxidant extracts was determined through the Folin-Ciocalteu method in terms of gallic acid equivalent (GAE). The oxidation stability of fuel samples with the addition of antioxidant extracts was estimated by the Rancimat method in terms of the induction period (IP). As a result, the scavenging effect in percentage for sesame, horse gram, sweet basil, coffee, and peas were 88.76%, 86.51%, 75.28%, 74.15%, and 70.78% at 1500 ppm, respectively. Besides, the total phenol content (mg GAE/100 g) for sesame, horse gram, sweet basil, coffee, and peas observed are 97.37, 39.99, 35.07, 30.15, and 25.25, respectively. More interestingly, adding antioxidants extracted from sesame, horse gram, sweet basil, coffee, and peas could increase the IP of the Jatropha biodiesel-lemongrass oil binary blend to 9.92, 8.10, 7.74, 7.10, and 4.10 hours, respectively compared to the case of binary blend without antioxidant (only 2.06 hours). In general, the inclusion of natural antioxidants additives increased the oxidation stability of biodiesel, promoting its prolonged storage, and the overall effectiveness of selected natural antioxidants was found to be in the order of sesame > horse gram > sweet basil > coffee > peas. Highlights The incorporation of a binary biodiesel blend reduces the cost of biodiesel synthesis. Replacement of synthetic antioxidant additive with natural antioxidant additive. Natural antioxidant addition enhances the storage stability of binary biodiesel blend.

Costs to Reduce the Human Health Toxicity of Biogas Engine Emissions

The anaerobic digestion of biodegradable substrates and waste is a well-known process that can be used worldwide to produce a renewable fuel called biogas. At the time of writing, the most widespread way of using biogas is its direct usage in combined heat and power internal combustion engines (CHP-ICEs) to generate electricity and heat. However, the combustion process generates emissions, which in turn have an impact on human health. Therefore, there is a need to: (i) measure the ICE emissions (both regulated and unregulated), (ii) compute the impact on human health, (iii) identify the substances with the highest impact and (iv) calculate the avoided damage to human health per Euro of investment in technology able to abate the specific type of pollutant. To this end, the authors conducted an experimental campaign and selected as a test case a 999 kWel biogas internal combustion engine. Then, the collected data, which included both regulated and unregulated emissions, were used to calculate the harmfulness to human health and identify the more impactful compounds. Thus, combining the results of the impact analysis on human health and the outcomes of a market analysis, the avoided damage to human health per Euro of investment in an abatement technology was computed. In this manner, a single parameter, expressed in DALY €−1, provided clear information on the costs to reduce each disability-adjusted life year (DALY). The impact analysis on human health, which was performed using the Health Impact Assessment, showed that NOx was the main contributor to damage to human health (approximately 91% of the total), followed by SOx (6.5%), volatile organic compounds (1.4%) and CO (0.7%). Starting from these outcomes, the performed investigation showed that the technology that guarantees the maximum damage reduction per unit of cost is the denitrification system or the oxidizing converter, depending on whether the considered plant is already in-operation or newly built. This is an unexpected conclusion considering that the most impacting emission is the NOx.

Ignition delay and its influence on the performance of a Diesel engine operating with different Diesel–biodiesel fuels

The ignition delay is an important parameter which characterizes the initiation of combustion process and consequently its development in Diesel engines. This parameter mainly depends on chemical factors which are related to the fuel structure and its properties and also on physical factors which are related to the engine operating conditions. The need for alternative fuels usage in Diesel engines determined by the depletion of petroleum resources and by the regulations imposed on pollutant emissions have enforced the researches on renewable biofuels. Among these new fuels, biodiesel B7, actually in use, and biodiesel B20, in prospective, have received a particular interest. In this sense, an experimental and theoretical study was performed on a tractor Diesel engine aiming to determine the ignition delay of the rapeseed biodiesel B7 and B20 and to compare them with the ignition delay of pure Diesel fuel for full load and different engine speeds as tested operating conditions. This present study represents an extension of the previously mentioned research having now as objectives: to review what are the methods used for the ignition delay evaluation, to perform a comparison between several commonly Arrhenius type relationships used for the assessment of ignition delay and the ignition delay experimentally determined, and to offer a better understanding of the influences induced by the ignition delay respectively by the fuel reactivity on performance, efficiency and emissions of compression ignited engines operating with different Diesel–biodiesel fuels. The novelty of this work consists in the statistical approach to probability density of ignition delay which leads to better estimation of this crucial parameter and consequently to better control of the combustion process.

Qualitative and energy recovery potential analysis: plastic-derived fuel oil versus conventional diesel oil

Due to depleting fossil fuel sources, plastic-derived fuel oil (PDFO) has received much attention over the past decade as an alternative to conventional diesel oil. Although several researchers have reported the properties of PDFO and recommended its usage in diesel engines, no study has thoroughly compared it with conventional diesel oil. This study aims at comparing PDFO produced from pyrolysis of waste plastic (LDPE, HDPE, PS, and PP) with conventional diesel oil based on a number of quality parameters and energy recovery potential. The quality parameters of color and appearance, water content, density, viscosity, volatility, copper strip corrosion, flash point, pour point, and energy content, as well as the cetane index of the fuels, were assessed following ASTM standards. The obtained results indicated no significant difference between the water contents and densities of the fuel oils. Pensky–Martens Closed Cup (PMCC) flash point for PDFO was significantly lower than that of conventional diesel oil. Although the pour points and viscosities of PDFO were significantly different from conventional diesel oil, the values were within the recommended range. All the PDFO types had higher volatilities than conventional diesel oil in the lighter section of the distillation curve, whereas no significant difference was detected in the heavier section. On the ASTM corrosion chart, conventional diesel oil belongs to class 1a, whereas all the PDFO types belong to class 2a. Energy recovery calculations revealed that PDFO has the potential to produce energy equivalent to 203,000 barrels of oil. It can be concluded that although PDFO has undesirable high volatility in the lighter section of the distillation curve and relatively low flash point, it compares relatively well with conventional diesel oil and thus is a potential substitute.

Aqueous phase recycling in catalytic hydrothermal liquefaction for algal biomass and the effect on elemental accumulation and energy efficiency

Abstract Generating green-based liquid fuels using hydrothermal liquefaction is a promising method for fossil fuel replacement. This study investigates the impact of recycling the aqueous phase in hydrothermal liquefaction processing on fuel yield, quality and energy efficiency using algae as the feedstock. Recycling the aqueous phase in algal hydrothermal liquefaction increased biocrude production yield by 18.9% at 350 °C, although a 12.2% increase in the biocrude nitrogen content was observed. In the second recycling, the nitrogen content increased to 17.6%, which is not environmentally favourable for direct usage in diesel engines due to the possible increase in Nitrogen Oxides (NOx) emissions. Recycling the aqueous phase in Spirulina Platensis feedstock liquefaction led to a 19–30% increase in yields for different recycling numbers, which was influenced by increasing the temperature and by applying catalysts. The heterogeneous catalyst showed a considerable increase (17.8%) in yield, a decrease (9.5%) in nitrogen content, and an improved energy consumption recovery by 30.8% after single recycling. However, a slight increase (2.7%) in nitrogen content was observed after recycling twice. It is vital to reduce the amount of energy used in the hydrothermal liquefaction process to be comparable with conventional fuels. Recycling the aqueous phase reduced the energy usage considerably. Applying the homogeneous catalyst and recycling the aqueous phase twice had the highest energy efficiency (36.8%) and production yield (51.4%) for the hydrothermal liquefaction process. The generated aqueous phase in single and double recycling experiments had up to 77% and 166% more phosphate, which may be of interest for agricultural applications.

Investigations on biogas fuelled Homogeneous Charged Compression Ignition engine with Di ethyl ether -Biodiesel-Butanol blend as Pilot fuel

The continuous and increasing in volume of fossil fuels utilization leads to an alarming increase in green-house gases emissions. Consequentially, the release of toxic agents may cause detrimental health issues and aggravate global warming effects. Biofuels, due to its reduced emission effects, are found to be a potential alternate to fossil fuels, especially for their usage in internal combustion engines under certain loading conditions. The present research work aims at investigating the effects of butanol blending ratio at different biogas flow rates on the performance and emission characteristics of a single-cylinder CI (Compression ignition) engine under Homogenous Charge Compression Ignition (HCCI) mode. Flow rates of biogas taken in the present study are 12 lpm and 16 lpm whereas the butanol is blended in biodiesel – DEE (Diethyl-ether) mixture at 10, 20 & 30% concentration by volume. The engine parameters analysed in the present work are brake thermal efficiency, Brake Specific Energy Consumption (BSEC), Hydrocarbons (HC), Carbon monoxide (CO), Oxides of Nitrogen (NOx) and Smoke emissions. Results showed that the butanol addition in the fuel reduced the NOx emissions considerably at various loads between 0.1 N-m to 15 N-m. Further increase in load resulted in knocking conditions in the engine due to multipoint ignition. Based on the experiments, it is witnessed that 30% of butanol blend in biodiesel-DEE mixture high efficiency and low smoke emissions compared to all other blends. Simultaneous reduction of NOx and smoke emissions is observed in HCCI mode.

Nonthermal vibrations in biased molecular junctions.

We study vibrational statistics in current-carrying model molecular junctions using a master equation approach. In particular, we concentrate on the validity of using an effective temperature T_{eff} to characterize the nonequilibrium steady state of a vibrational mode. We identify cases in which a single T_{eff} cannot fully describe one vibrational state. In such cases, the probability distribution among different vibrational states does not follow the Boltzmann type. Consequently, the actual entropy (free energy) of the vibrational mode is lower (higher) than the corresponding thermal value given by T_{eff}, indicating extra work can be extracted from these states. Our results will be useful for the study of a nonthermal vibrational state in the thermodynamics of nanoscale systems, and its usage in nanoscale heat engines.

Improving biodiesel made from cottonseed and soyabean oil with partial hydrogenation

Biodiesel limitations such as poor cold-flow properties and oxidation stability limit its usage in diesel engines. Partial hydrogenation is reported to be one of the ways to improve these limitations. Partial hydrogenation of biodiesel made from cottonseed and soyabean oil was studied. Before and after hydrogenation, the fatty acid methyl ester contents of cottonseed and soyabean biodiesel were detected with gas chromatography–mass spectrometry. It was revealed that methyl linolenic and methyl linoleic decreased while methyl stearic and methyl oleic increased after the partial hydrogenation for both soyabean and cottonseed biodiesel. Methyl oleic increased by 127 and 237% for soyabean and cottonseed biodiesel, respectively. A thermogravimetric test was also conducted on the fuel samples to observe the volatilisation of the fuels. There was an increase in fuel properties such as cetane number and kinematic viscosity, while iodine value decreased after partial hydrogenation. In addition, there was no significant change in oxygen content, low-heat value and density for both soyabean and cottonseed biodiesel. In summary, partial hydrogenation is a good method of upgrading biodiesel fuel properties such as cold-flow properties and oxidation stability.

A review of hydrogen usage in internal combustion engines (gasoline-Lpg-diesel) from combustion performance aspect

Demand for fossil fuels is increasing day by day with the increase in industrialization and energy demand in the world. For this reason, many countries are looking for alternative energy sources against this increasing energy demand. Hydrogen is an alternative fuel with high efficiency and superior properties. The development of hydrogen-powered vehicles in the transport sector is expected to reduce fuel consumption and air pollution from exhaust emissions. In this study, the use of hydrogen as a fuel in vehicles and the current experimental studies in the literature are examined and the results of using hydrogen as an additional fuel are investigated. The effects of hydrogen usage on engine performance and exhaust emissions as an additional fuel to internal combustion gasoline, diesel and LPG engines are explained. Depending on the amount of hydrogen added to the fuel system, the engine power and torque are increased at most on petrol engines, while they are decreased on LPG and diesel engines. In terms of chemical products, the emissions of harmful exhaust gases in gasoline and LPG engines are reduced, while some diesel engines increase nitrogen oxide levels. In addition, it is understood that there will be a positive effect on the environment, due to hydrogen usage in all engine types.