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This review paper summarizes the current state-of-the-art of the chemical transformation of oils/fats (i.e., triacylglycerols) to the use of biofuels or bio-lubricants in the means of transport, which is a novelty. The chemical transformation is necessary to obtain products that are more usable with properties corresponding to fuels synthesized from crude oil. Two types of fuels are described-biodiesel (the mixture of methyl esters produced by transesterification) and green diesel (paraffins produced by hydrogenation of oils). Moreover, three bio-lubricant synthesis methods are described. The transformation, which is usually catalysed, depends on: (i) the type and composition of the raw material, including alcohols for biodiesel production and hydrogen for green diesel; (ii) the type of the catalyst in the case of catalysed reactions; (iii) the reaction conditions; and (iv) types of final products. The most important catalysts, especially heterogeneous and including reaction conditions, for each product are described. The properties of biodiesel and green diesel and a comparison with diesel from crude oil are also discussed. Review sumarizuje současný stav výzkumu chemické transformace olejů a tuků na bionaftu a biolubrikanty s využitím katalyzovaných procesů. Různé typy výchozích materiálů, katalyzátorů, reakčních podmínek a finálních produktů jsou popsány.

Cílem tohoto článku je shrnout možnosti voltametrického stanovení antioxidantů v průmyslových palivech a mazivech. Analýza antioxidantů v palivech a mazivech je důležitá z hlediska vzniků odpadů zejména proto, že zbytečně častá výměna olejů vede k nadbytečné produkci odpadních olejů a naopak jejich nedostatečná výměna může zapříčinit až poškození mazaných součástí. Voltametrické techniky umožňují rychlé, precizní, správné, a na rozdíl od jiných dosud používaných analytických přístupů, i poměrně levné stanovení těchto elektrochemicky aktivních látek. Voltametrická analýza antioxidantů je založena na sledování jejich elektrochemické oxidace v prostředí kyseliny sírové. Pro jejich monitoring byly využívány pracovní elektrody na bázi zlata a bórem dopovaného diamantu. V rámci této publikace jsou shrnuty možnosti stanovení běžně používaných antioxidantů a to konkrétně 2,6-di-terc-butyl-4-methylfenolu (butylhydroxytoluenu, BHT), 2-terc-butylfenolu (2-TBF), 2- a 3-terc-butylhydroxyanisolu (směs izomerů, BHA), terc-butylhydrochinonu (TBHQ), propylgalátu (PG), pyrogalolu (PY) a N-fenyl-1-naftylaminu (PNA). Kromě stanovení jednotlivých antioxidantů byly také vypracovány postupy pro analýzu jejich směsí. Navržené metody byly úspěšně aplikovány na analýzu vzorků maziv a paliv s velmi dobrými výsledky. The aim of this paper is to summarize possibilities of voltammetric determination of antioxidants in fuels and oils. Voltammetric techniques provide fast, precise, proper, and in comparison with so far applied analytical tools, relatively low cost analytical approach for determination of these electroactive compounds. Considering the waste production, analysis of antioxidants provides important information about oxidation stability and prevents unnecessarily frequent change of oils leading to the waste generation. Moreover, the exhaustion of antioxidants in the particular oil or fuel could lead to the damage or even to the destruction of lubricated components or engines. Voltammetric analysis of antioxidants is based on monitoring of their electro-oxidation in acidic media namely in the diluted sulfuric acid. Gold disc and boron-doped diamond electrode, respectively, was employed as a working electrode for monitoring of the followed commonly applied antioxidants: 2,6-di-tert-butyl-4-methylphenole (butylhydroxytoluen, BHT), 2-tert-butylphenol (2-TBF), 2- and 3-terc- butylhydroxyanisoles (mixture of isomers, BHA), terc-butylhydroquinone (TBHQ), propyl gallate (PG), pyrogallol (PY), and N-phenyl-1-naphthylamine (PNA). Besides determination of the individuals, the proposed method was successfully applied for analysis of the antioxidant mixtures. Samples of the mineral and synthetic oils and the biofuels were analyzed with excellent results as well.

The bachelor thesis deals with the production, distribution and significance of motor fuels from biomass. From a brief summary of some very basic, but also most biofuels to those currently in the unused but potentially significant. Assessment of the advantages and disadvantages of biomass fuels compared to fossil fuels and biofuels characteristic of the first, second and third generation. This paper presents a summary of findings Czech and foreign experts over the last few years.

Thesis is concentrated on two biotechnologies: biofuels and genetically modified crops. Defines technical and economical characteristics, lists international agreements and czech and european legislation regarding both biotechnologies. Introduces opinions and analyses positions of selected political subjects as UNO, WTO, OECD, EU, catholic church and main czech political parties.