Complex intermetallic compounds are a promising alternative to catalysts containing noble metals. Phases containing aluminium and transition metals revealed high activity and selectivity to desired products in hydrogenation reactions in liquid and gas environments. Especially interesting are compounds containing aluminium and iron due to the availability and favourable price of these elements, e.g. the Al13Fe4 phase, which in the acetylene hydrogenation reaction showed a catalytic performance comparable to the standard industrial catalyst. Al13Fe4 is a complex intermetallic compound, an approximant of decagonal quasicrystal found in the Al-Ni-Fe system. The presented study aims to manufacture melt-spun ribbons containing a decagonal quasicrystalline phase and to verify the catalytic potential of this material.

Alloys with composition relating to the Al-Ni-Fe decagonal quasicrystal have been produced by the melt-spinning process. The microstructure, phase and chemical composition of obtained ribbons were examined by X-ray diffraction (XRD), scanning (SEM) and transmission electron microscopy (TEM). Pulverised ribbons were used as a catalyst for the phenylacetylene hydrogenation. The composition of the reaction mixture was evaluated by gas chromatography.

Melt-spun ribbons revealed a complex microstructure containing dendrites, eutectics and equiaxed grains. The morphology of the ribbon varied in different areas of the ribbon. XRD and TEM studies indicate the presence of the following phases: Al13Fe4, AlNi, Al5FeNi and the decagonal quasicrystalline phase. The complexity of manufactured material may result from the narrow composition range of the decagonal quasicrystalline phase in the phase diagram and the conditions of the melt-spinning process. The catalytic properties of obtained material were tested using pulverised ribbons under mild reaction conditions (50 °C, 5 bar H2). Despite the multiphase composition of the material, over 90% of the substrate conversion was achieved after 1h. Selectivity to styrene reached a value of 50%. Further work will aim to obtain a single-phase decagonal quasicrystal composition by adjusting the chemical composition in the range of occurrence of desired phase and manufacturing conditions. Then, the catalytic performance of obtained material will be evaluated and compared with multiphase material.