Biofuels have become an integral part of everyday life in modern society. Bioethanol and fatty acid methyl esters are a common part of both the production of gasoline and diesel fuels. Also, pressure on replacing fossil fuels with bio-components is constantly growing. Waste vegetable fats can replace biodiesel. Hydrotreated vegetable oil (HVO) seems to be a better alternative. This fuel has a higher oxidation stability for storage purposes, a lower temperature of loss of filterability for the winter time, a lower boiling point for cold starts, and more. Viscosity, density, cold filter plugging point of fuel blend, and flash point have been measured to confirm that a fuel from HVO is so close to a fuel standard that it is possible to use it in engines without modification. The objective of this article is to show the properties of different fuels with and without HVO admixtures and to prove the suitability of using HVO compared to FAME. HVO can also be prepared from waste materials, and no major modifications of existing refinery facilities are required. No technology in either investment or engine adaptation of fuel oils is needed in fuel processing.

Müller M., Horníčková Š., Hrabě P., Mařík J. (2015): Analysis of physical, mechanical and chemical properties of seeds and kernels of Jatropha curcas. Res. Agr. Eng., 61: 99-105.The research was performed to examine the physical, mechanical and chemical properties of seeds and kernels of Jatropha curcas. The test parameters were the dimensions of the seeds and kernels, required energy for oil extraction, determination of fatty acids in the oil by gas chromatography method, determination of the iodine value, determination of the acid value, determination of total polyphenols by the Folin & Ciocault reagent and determination of tocopherols and tocotrienols (vitamin E) by High-performance liquid chromatography. It was ascertained that the size of the seed and kernel varies considerably. Pressing of whole seeds needs more energy (50%) than pressing of kernels. From a chemical point of view it seems to be very appropriate for a production of biofuels. Jatropha curcas contains more polyphenols and vitamin E, which act as antioxidants, than the rape. Due to the low content of unsaturated fatty acids it is chemically suitable to replace the rape-seed oil with Jatropha curcas oil.

Biobutanol is a renewable, less polluting, and potentially viable alternative fuel to conventional gasoline. Biobutanol can be produced from same sources as bioethanol, and it has many advantages over the widespread bioethanol. This paper systematically analyzes biobutanol fuel as an alternative to bioethanol in alcohol–gasoline mixtures and the physicochemical properties. Based on the conducted analyses, it was found that biobutanol mixtures have a more suitable behavior of vapor pressure without the occurrence of azeotrope, do not form a separate phase in lower temperature, it has higher energy density, but slightly reduce the octane number and a have higher viscosity. However, in general, biobutanol has many advantageous properties that could allow its use in gasoline engines instead of the commonly used bioethanol.

Road transport is increasing all around the globe and biofuels have come to the forefront of public interest. According to Article 3, Directive 2009/28/EC, each member state has to ensure that an energy share from renewable sources in all forms of transportation reaches at least 10% of the final consumption of energy in transportation until 2020. The blending of biofuels is one of the methods available to member states to meet this target and it might even be expected to be a main contributor. This article analyses and compares selected biofuels, their chemical properties and their influence on engine operational parameters. The operational parameters of the diesel engine of the Skoda Roomster 1.4 TDI were measured on a chassis dynamometer according to the NEDC driving cycle, and pure diesel fuel, HVO and a blend of fuels (diesel fuel, HVO and butanol) were used for comparison. Operation on biofuels shows a slight decrease in performance parameters up to 10% and an increase in emission production (especially CO in the case of D50H30B20). Positive influences of biofuels were proven with a decrease in exhaust gas opacity and particulate matter production, up to 50% in the case of D50H30B20.

EU is heading to efforts to promote the use of biofuels. Biofuels are replaced fossil fuels only partially. They are produced by a mixture of fossil fuels and biofuels. For spark ignition engines, the most widely used biofuel E85, a fuel containing 85% ethanol and 15% gasoline. The more biologist is contained in the fuel is thus suffer more from oil charge combustion engine. Therefore, in the paper presented a comparison of the properties of the oil filling when using of fossil fuels (currently contains a small amount of the fuel ethanol) and E85 biofuel. Were monitored passenger vehicle brand Saab 95, namely engine B235 R. From the car was removed a total of 10 samples of engine oil. One part of the samples were removed during operation of the internal combustion engine to the biofuel E85 and the second at operation of the internal combustion engine currently available fossil fuel BA95. The internal combustion engine is used for lubricating motor oil Mobil 1 0W-40th Analysis engine oil are focused on the evaluation of viscosity, density and lubricity.