The need to find sustainable alternatives to fossil fuels in aviation without requiring drastic structural changes in turbines and tanks has prompted a search for new components to blend with the standard Jet A1. Turpentine obtained by vacuum distillation of resin extracted from the common pine Pinus pinaster or as a byproduct of the paper industry is compared with hydrogenated turpentine at different levels of conversion as a component of jet blends. Properties such as density, kinematic viscosity, heating values, lubricity, flash point, pour point, crystallization onset temperature, and smoke point are reported. Turpentine shows high soot formation tendency. Hydrogenation was carried out as a method to saturate the double bonds of pinenes and to overcome this problem. The performance of four hydrogenated turpentines at different levels of turpentine–hydroturpentine conversion proves improvements in some key properties and especially reductions in the sooting tendency, concluding that partially hydrogenated turpentine can be blended up to 50% v/v with Jet A1, fulfilling the limit required by the standard specification for aviation turbine fuels containing synthesized hydrocarbons.

In Europe, recent regulations on advanced biofuels have prompted a search for new fuel sources and the development of synthesis methods meeting the demanding specifications of the sector. However, in developing countries such as Algeria, where a significant stock of frying oil is unused, the use of diesel engines powered with waste-oil-derived biofuels must be explored. In this work, the variables related to the transesterification reaction from this frying oil with ethanol are analyzed using response surface methodology. From this analysis, only the reaction time and temperature have been determined as relevant parameters. In addition, FT-IR analysis has proven a useful tool to analyse the conversion in the transesterification reaction of waste frying oil with ethanol and is cheaper and quicker than GC-FID. This sustainable biofuel (FAEE), mixed with a diesel and pure fuel, has been physically characterized. The mixture of FAEE at 30% by volume with diesel meets the requirements demanded in standard EN 590 and can be classified as winter diesel class D. As a pure biofuel, only its high cold flow temperatures could constitute a drawback for exporting to temperate climates but not for internal consumption. Graphical Abstract Electronic supplementary material The online version of this article (10.1007/s12649-020-01149-4) contains supplementary material, which is available to authorized users.

Transformation of turpentine by catalytic hydrogenation and oxyfunctionalization enhances notably the diesel properties. Particularly, oxyturpentine improves the soot tendency and hydroturpentine the cold flow properties.

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Wine industry generates a large amount of biowaste, such as grape marc and wine lees, which is considered in the Directive (EU) 2018/2001 as an adequate feedstock to produce advanced biofuels. Grapeseed oil fatty acid ethyl esters (FAEEs) can be obtained from oil extracted from grape marc and bioethanol distilled from wine lees or wine surplus. Although FAEE still has no specific standard, grapeseed oil FAEE would fulfill all of the properties set by the standard EN 14214, except oxidation stability. This work analyzes the effect of natural antioxidants on the oxidation stability of grapeseed oil FAEE, using grapeseed oil fatty acid methyl esters (FAMEs) as a reference for comparison. On the one hand, the biofuel, produced with conventional transesterification, was mixed with FAME and FAEE produced via in situ transesterification. On the other hand, antioxidants extracted from grapeseed or defatted grapeseed flour were added to the biofuel. The results show that (1) FAEE has worse oxidation stability than FAME, (2) in situ transesterification improves the oxidation stability, and (3) addition of natural antioxidants is hindered by their low solubility in alkyl esters. Finally, the concentration of antioxidants, measured by UV–vis spectroscopy, showed a correlation between the absorbance at 285 nm (characteristic of phenolic compounds) and the induction time (IT) of the samples.