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Problems with the low-temperature operability performance of biodiesel in blends with petroleum diesel are infrequent, but continue to limit the use of biodiesel during winter months. A troubling aspect of this problem is that in some cases precipitates above the blend Cloud Point (CP) have been detected and have led to plugging of fuel filters and subsequent engine stalling, as well as plugging of fuel dispenser filters. Many researchers found that the saturated monoglyceride content was a main component of the material that was found on plugged fuel filters, as well as traces of Saturated DiGlycerides (SDG), were also present on the plugged fuel filters. This is the reason which forced the organization of standardization to suggest a procedure in order to predict the content of the Saturated MonoGlycerides (SMG) even with uncertainty which can vary from −50% to +50%. The model which was used will be the same as that which was introduced in the Annex C of EN 14214+A1:2013.

According to the existing maritime regulation, the marine diesel equipment will be necessary to operate with low sulfur marine fuels. Low Sulfur Middle Gas Oils (MGOs) often have a viscosity that is lower than that of Heavy Fuel Oil (HFO). The problems in diesel engines are mainly related to high pressure fuel pumps that depend on the fuel oil for their lubrication. A solution to that problem probably will be the addition of Fatty Acid Methyl Esters (FAME) as an additive to the fuel. On the other hand, for the purposes of International Standard ISO 8217:2012 in the case of distillate fuels it is recommended that “de minimis” level of FAME is recommended. “De minimis” level is determined approximately as the 0.1% volume of the fuel. In this study, Distillate Marine Diesel Oil with good lubricity performance was used blended with FAME fuel, according to national and European Standard (ELOT EN 14214), was used as an additive.

The ability of a catalyst to enhance the performance of synthesized biobased lubricant basestock was investigated in this study. Pomace olive oil, cottonseed oil, used frying oil and methyl oleate were utilized as starting materials for the production of the biobased lubricants and a two stages transesterification methodology was followed. Initially the oils were converted to their corresponding fatty acid methyl esters via methanolysis. The resulting methylesters were subsequently transesterified with TMP producing the desired oleochemical ester. These syntheses were carried out in the presence of either sodium methoxide or Ca/TEA alkoxide as catalysts. Following the purification phase, the synthesized esters were evaluated as potential biolubricants regarding their physicochemical properties such as viscosity index, pour point and acid value.

The aim of this study was to synthesize environmentally adapted Trimethylolpropane (TMP) esters from cottonseed and soybean oils and to examine their quality parameters and tribological properties as potential lubricant basestocks. A two stage production process was followed. At first the above mentioned vegetable oils were transformed to the corresponding methyl esters via methanolysis in the presence of sodium methoxide. The desired TMP esters were finally synthesized by alkaline transesterification of the previously produced methylesters with TMP using sodium methoxide as catalyst. Following the purification phase the physicochemical characteristics of the synthesized TMP esters were examined. The tribological properties were evaluated by employing a Four-Ball apparatus. An additive-free mineral oil base oil was used as a reference lubricating fluid.

Air pollution caused by diesel emissions, especially NOx, particulate matter, carbon monoxide and unburned hydrocarbons, has been a noteworthy matter. In Europe and the United States, legislative efforts towards improving air quality not only lead manufacturers to develop and introduce further improved emission control systems, but also the trigger demanding requirements on the oil industry towards producing advanced fuels. Therefore, much work on the effects of fuel properties on the emissions and engine performance has been performed worldwide. The fuels produced by the refineries usually comply with the existing specifications. However, alterations in the fuel properties may occur through the supply chain to the service stations due to failures of the distribution system or adulteration with lower value and taxation fuels (heating oil, marine diesel or industrial solvents).

To reduce the fuel related logistic burden, NATO Armed Forces are advancing the use of a single fuel for both aircraft and ground equipment. To this end, F-34 is replacing distillate diesel fuel in many applications. Yet, unacceptable wear due to poor lubricity was illustrated by tests conducted with kerosene on High Frequency Reciprocating Rig. Therefore, HFRR tests were performed with fatty acid methyl esters of sunflower, palm, cotton-seed, tobacco-seed, olive, rape-seed and used frying oils, at volume concentrations from 0.05% to 0.6%. This study showed that the biodiesels used, produced a significant decrease in the wear scar diameter at concentrations of 0.2% to 0.4 %. Biodiesels derived from non-polyunsaturated oils, such as palm and olive gave better lubrication at certain concentrations.