This paper aims to increase the sorption capacity of hydroxyapatite and to find the best apatite-based material for metal ions sorption. The sorption process of copper ions from water solutions by HAP and structurally modified HAP was carried out in this work. Structural modifications of HAP were realized in the preparation phase by an addition of sodium silica into the reaction medium. The prepared materials were characterized by physical-chemical methods: IR, electron-microscopy and X-ray diffraction. The composites characterized were tested in kinetic studies regarding ion exchange and adsorption of Cu2+. It was revealed that the silica content, particle size and initial copper ion concentration influence the process rate.

While various reactions in the inorganic subset of the oscillatory Briggs-Rauscher (BR) reaction were clarified in the recent years, the organic subset of the present mechanisms contains only one process: the iodination of malonic acid. Further organic reactions can play a role, however, if malonic (MA) and iodomalonic (IMA) acids can be oxidized in the BR reaction. As CO2 and CO should be products if such oxidations can take place, the main aim of this work was to learn whether these gases are produced in a significant amount in a BR system. In our BR experiments, a rather intense evolution of both gases was observed with an oscillatory and a nonoscillatory component. With the initial conditions applied here, one from every 6 carbon atoms was oxidized either to CO2 or to CO in the course of the BR reaction. The amount of CO2 was about 4 times higher than that of CO. Experiments are in progress to disclose the reactions which generate the measured gases and their role in the mechanism of the BR reaction.

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The alkylation of light hydrocarbons leads to produce the high octane number gasoline blending components. The homogeneous catalytic alkylation reaction is usually carried out at low temperature in the presence of H 2 SO 4 and HF. The use of heterogeneous catalysis for this reaction is a promising solution for the replacement of hazardous acids to environmentally friendly zeolite catalyst. The alkylation reaction of isobutane with 1-butene was studied on selected zeolite catalysts. The objective of the research was to study the mechanism of the alkylation reaction with taking the rate determining step and irreversible step into consideration.