Effect of alcoholic and nano-particles additives on tribological properties of diesel–palm–sesame–biodiesel blends

This study focused on evaluating the lubricity of diesel–biodiesel fuel with oxygenated alcoholic and nano-particle additives. Fuel injection system lubrication depended primarily on the fuel used in the diesel engine. Palm–sesame oil blend was used to produce biodiesel using the ultrasound-assisted technique. B30 fuel sample as a base fuel was blended with fuel additives in different proportions prior to tribological behavior analysis. The lubricity of fuel samples measured using HFRR in accordance with the standard method ASTM D6079. All tested fuels’ Tribological behavior examined through worn steel balls and plates using scanning electron microscopy (SEM) to assess wear scar diameter and surface morphology. During the test run, the friction coefficient was measured directly by the HFRR tribometer system. The results exhibited that B10 (diesel) had a very poor coefficient of friction and wear scar diameter, among other tested fuels. The addition of oxygenated alcohol (ethanol) as a fuel additive in the B30 fuel sample decreased the lubricity of fuel and increased the wear and friction coefficient, among other fuel additives. B30 with DMC showed the least wear scar diameter among all tested fuels. B30 with nanoparticle TiO2 exhibited the best results with the least wear scar diameter and lowest friction coefficient among all other fuel samples. B30+DMC demonstrated significant improvement in engine performance (BTE) and carbon emissions compared to different tested samples. B30+TiO2 also showed considerable improvement in engine characteristics

A review on bio-based lubricants and their applications

In transportation and industrial sectors, the world relies heavily on petroleum-based products which may cause grave concern related to future energy security. On certain cases, these products would end up back to the environment causing serious environmental pollution and hazards. Recognized as potential substitutes to mineral-based lubricants, bio-based lubricants have received growing interest as they play a significant role in overcoming above problems. Bio-based lubricants have been found to exhibit superior lubricant properties over the conventional mineral lubricants, with renewability and biodegradability being their strongest suit. There is a strong need to review the available literature to explore the potential of bio-based lubricants for various applications. In this regard, the goal of this paper is to highlight the potential of biolubricants for a broad range of applications based upon the published researches over the past decade. The correlation between molecular structures, physicochemical properties and lubrication performance of natural oil were reviewed which is essential for lubricant development and selection. This review also acknowledged some applications of which the potential use of bio-based lubricant has been explored. Based on the key findings, it can be concluded that bio-based lubricant is a promising substitute for various applications due to their availability in wide arrays of properties which are essential for some applications. However, for certain applications, prior chemical modification is required to overcome the limitations including substandard low temperature characteristics and oxidative stability. With proper base oil and additive packages formulation, bio-based lubricants can perform better than the conventional lubricants

Performance and emission characteristics of a spark ignition engine fuelled with butanol isomer-gasoline blends

The heavy reliance on petroleum-derived fuels such as gasoline in the transportation sector is one of the major causes of environmental pollution. For this reason, there is a critical need to develop cleaner alternative fuels. Butanol is an alcohol with four different isomers that can be blended with gasoline to produce cleaner alternative fuels because of their favourable physicochemical properties compared to ethanol. This study examined the effect of butanol isomer-gasoline blends on the performance and emission characteristics of a spark ignition engine. The butanol isomers; n-butanol, sec-butanol, tert-butanol and isobutanol are mixed with pure gasoline at a volume fraction of 20 vol%, and the physicochemical properties of these blends are measured. Tests are conducted on a SI engine at full throttle condition within an engine speed range of 1000–5000 rpm. The results show that there is a significant increase in the engine torque, brake power, brake specific fuel consumption and CO2 emissions with respect to those for pure gasoline. The butanol isomers-gasoline blends give slightly higher brake thermal efficiency and exhaust gas temperature than pure gasoline at higher engine speeds. The iBu20 blend (20 vol% of isobutanol in gasoline) gives the highest engine torque, brake power and brake thermal efficiency among all of the blends tested in this study. The isobutanol and n-butanol blend results in the lowest CO and HC emissions, respectively. In addition, all of the butanol isomer-gasoline blends yield lower NO emissions except for the isobutanol-gasoline blend

Production optimization and tribological characteristics of cottonseed oil methyl ester

This paper presented experimental results to evaluate the optimization of production parameters through response surface methodology. These parameters significantly affected the yield of cottonseed oil methyl ester (COME). The input variables for the production of methyl ester from cottonseed oil were methanol/oil molar ratio, concentration of catalyst, temperature, and stirring speed. The response or output variable was the yield of methyl ester. The fatty acid methyl ester composition of COME (biodiesel) was obtained using a gas chromatography (GC) analyzer. BS EN 14103:2011 was the standard used to analyze the fatty acid methyl ester. The derived mathematical model was statistically accurate to predict the optimum value of COME. The optimized values to obtain a 98.3% yield of methyl ester were as follows: methanol/oil molar ratio of 6:1, catalyst concentration of 0.97% (w/w), temperature of 63.8 °C, and speed of 797 rpm. The physicochemical properties of COME were measured in accordance with ASTM D6751. The friction and wear properties of COME and its blends with petroleum diesel were tested using a four-ball wear testing machine. The tribological characteristics of COME as a new biofuel were assessed. COME displayed good lubricity with a low coefficient of friction and wear scar diameter. The coefficient of friction of pure COME (COME100) was lower than that of pure petroleum diesel (DL100) and COME blends with petrol diesel (COME10, COME20, and COME50). The average coefficient of friction of COME 100 was lower than that of DL100, COME10, COME20, and COME50 by 28.06%, 19.49%, 7.49%, and 3.65%, respectively. The wear scar diameter of COME100 for the tested ball was lower than that of DL100, COME10, COME20, and COME50 by 47.6%, 33.3%, 32.1%, and 21.42%, respectively. The worn surfaces of the tested balls were examined by scanning electron microscopy, and the results were presented in this paper

Effect of TMP-based-cottonseed oil-biolubricant blends on tribological behavior of cylinder liner-piston ring combinations

Cottonseed oil-based biolubricant was synthesized by the TMP-based transesterification process. 10–50% by volume blends of TMP-based cotton-biolubricant and SAE-40 were prepared and tested on the high-frequency-reciprocating-rig with engine cylinder-liner and piston-ring combination to investigate their tribology. While tribological characteristics were also evaluated by four-ball tribo-testers at high constant load of 785 N. 10% addition of cotton-biolubricant showed the lowest friction and wear as compared to SAE-40 but>10% volume of cotton biolubricant in blend increased the wear and friction considerably as tested by both HFRR and four-ball. Hence, 10% addition of TMP-cotton-biolubricant can be utilized as an energy-saving lubricant additive to partially reduce the dependency on petroleum-based lubricant for automotive engine application

Effect of gasoline-bioethanol blends on the properties and lubrication characteristics of commercial engine oil

Concerns over depleting fossil fuel reserves, energy security, and climate change have resulted in stringent legislation demanding that automobiles use more renewable fuels. Bioethanol is being given significant attention on a global scale and is being considered as a long-term gasoline replacement that helps reduce exhaust emissions. The piston ring and cylinder wall interface is generally the largest contributor to engine friction and these regions of the engine also suffer the highest levels of fuel dilution into the lubricant from unburned fuel, especially for bioethanol as it has a high heat of vaporization, which enhances the tendency of the fuel to enter the oil sump. As bioethanol is being blended with gasoline at increasingly higher concentrations and the accumulation of fuel in the crankcase is significant, it is crucial to study the effect of various bioethanol blends on the degradation of engine oil's properties and the friction and wear characteristics of engine oil. A fully synthetic oil was homogenously mixed with five formulated fuels such as gasoline blend (E0), gasoline-10% ethanol (E10), gasoline-20% ethanol (E20), gasoline-30% ethanol (E30), and gasoline-85% ethanol (E85). These mixtures were then tested in a four-ball wear tester according to the ASTM D4172 standard test. Under selected operating conditions, the results show that the addition of a gasoline-bioethanol blend decreases the oil viscosity, whereas the acid number increases because bioethanol is more reactive compared to gasoline, which enhances oil degradation and oxidation. Fuel dilution reduces the lubricating efficiency and the wear protection of the engine oil. All fuel-diluted oil samples have higher friction and wear losses, compared to the fresh synthetic oil. E10 has slight effects on the friction and wear behaviors of the engine oil. Thus, it still has a high potential to be widely used as a transportation fuel for existing gasoline engines