PROCESSING OF LIQUEFIED PETROLEUM GASES OVER MONO-AND BIMETALLIC CATALYSTS

Abstract

The reserves of liquefied petroleum gas in the production zones and fields are briefly characterized in present paper. The scope of liquefied petroleum gases application, catalytic transformation and their importance in obtaining products are described. Widespread use of nanostructured and nanoscale catalysts in catalysis processes and their properties are given in literature review. Chemical transformations of С3-С4-alkanes in the presence of mono- and bimetallic catalysts based on Cr/SiO2 are studied. By method of electron microscopy, it was determined that various highly dispersed oxides of chromium in lanthanum – modified catalyst interact with each other and with carrier. According to electronic paramagnetic resonance data, chromium is contained in a five- and three-valence state. Mono - and bimetallic catalysts were studied by physical and chemical methods: IR spectroscopy, electron microscopy (EM) using micro diffraction, EPR. Monometallic catalysts with a chromium content of 2-10 wt. % and bimetallic lanthanum-chromium-containing catalyst in the form of 5% La-Cr/SiO2 in a ratio of 1/1 were prepared in the work; the process temperature was varied in the range of 400 to 650°С. Introduction of lanthanum leads to the formation of LaCrO3, LaCrO4 compounds with low activity in dehydro-genation reaction of C3-C4 – alkanes. The maximum yield of C2-C4-olefins - 39.2%, i.e. the formation of propylene in high doses was observed in the presence of 5% Cr/SiO2.