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Rapeseed vegetable oil was initially zeoformed in the temperature range of 200°Cto 300°C and at a pressure of 1.7 MPa using catalyst containing ZSM-5, and the obtained zeoformates were subsequently converted into hydrocarbons (HVO: hydrorefined vegetable oil) through the process of hydroconversion. The resulting hydroraffinates (HVO fuel biocomponents) contained: n-paraffins, iso-paraffins and up to 15 % of aromatic compounds. It has been established that hydroraffinates containing aromatic compounds have good lowtemperature properties (cold filter plugging point (CFPP) of approximately -12°C) and a density of 825 kg/m 3 . The hydroraffinate obtained over the catalyst at the highest applied temperature (300°C) was characterised by a decreased initial boiling point of distillation (IBP) of 174°C (the IBP for the non-zeoformed oil hydroraffinate was 284°C) and an increased distillation final boiling point (the FBP) of approximately 379°C, which was higher than that of the nonhydroraffinate (337°C). Investigation of the obtained hydroraffinate properties led to the conclusion that the preliminary zeoforming process may cause the coupling (oligomerisation) of fatty acid chains and the creation of aromatic structures containing aliphatic functional groups.

Wet fine milling, as a pretreatment step to acid activation of vermiculite, was applied in order to decrease the environmental impact of the procedure commonly used to increase the mineral's adsorption capacity. Milling caused fragmentation of the material and several changes in its structure: edges of the flocks became frayed, the surface cracked, cation exchange capacity (CEC) increased, and most of the iron in oligonuclear and bulk form was removed. At the same time the specific surface area, crystallinity, chemical composition and adsorption capacity did not change significantly. Fine ground material was more susceptible to acid activation, which caused a decrease in the crystallinity and CEC, development of meso-and microporosity, an increase in the total volume of pores, in the specific surface and external surface areas. Micropores were developed faster in lower acid concentrations in the rough ground material, while the external surface area and total pores volume increased faster in the fine ground vermiculite. The latter material also had a higher CEC. Application of 0.5 mol L −1 HNO 3 to rough ground vermiculite did not change its adsorption capacity, however it changed from 55 ± 7 to 110 ± 8 mg g −1 when the material was fine ground. The optimal treatment conditions for both materials were obtained for 1.0 mol L −1 HNO 3 , however the adsorption capacity for the fine ground vermiculite increased more (i.e., from 55 ± 7 to 136 ± 7 mg g −1) than for its rough ground counterpart (i.e., 52 ± 7 to 93 ± 7 mg g −1). Concentrations higher than 1.0 mol L −1 resulted in deterioration of the adsorption capacities in both cases. Considering all the experimental outcomes, it can be concluded that the environmental impact of acid activation of vermiculite may be diminished by application of fine grinding of the material before the chemical activation process. Such treatment resulted in higher adsorption capacity at a given acid concentration compared to the rough ground material.

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