SEAL PRODUCTS AND THEIR ROLE IN THE PROCESS OF CONVERSION OF ISOBUTENE ON A HIGH SILICA ZEOLITE CATALYST

Abstract

Conversion of isobutene on a high silica zeolite catalyst in the temperature interval (473-773 K) has been studied. The formation of liquid reaction products is observed at the temperature 473 K, whereas gaseous products form after 523K. Maximum yield of liquid products is observed at the temperature 573 K and makes up 67 %. With increase of contact time the yield of liquid reaction products shifts towards high temperatures. Formation of aromatic hydrocarbons is observed at the reaction temperature higher than 573 K. At the temperature 673 K the main mass of liquid products consists of aromatic hydrocarbons. The activity of H-form of HSZ (HHSZ) in the process of conversion of isobutene in the formation of liquid reaction products occurs only when 6-8% of seal products accumulate on its surface. By the method of ammonia adsorption on the initial and coked catalyst their acidic properties have been studied. It was shown that at the beginning of the process decrease in acidic properties of the catalyst occurs due to accumulation of seal products on it. Key words: catalyst, activity, isobutene, zeolite, seal products, temperature, heterogen, chromatography, spectroscopy.