Catalysts based on zeolites and zeolite-like materials for processing light hydrocarbon feedstocks into motor fuel components

The current status of raw material resource base of liquid hydrocarbon crude is characterized by increase in its cost and decrease in production output. At the same time reserves of natural gas and solid fossil fuels dramatically exceed oil volumes [1-3]. Moreover significant quantity of so-called refinery gases are formed during crude petroleum refining at the oil refinery plants (ORP). The total yield of refinery gases at the oil refinery plants is on average 5-8% of the quantity of the refine oil, and at the petrochemical refinery plants this figure is notably higher [4, 15, 16]. The most large-capacity process of gas conversion process for light hydrocarbons such as natural, oil-associated and refinery gases is catalytic refining based on the alkylation processes and oligomerization. In spite of the fact that a large variety of catalytic agents find application in the oligomerization of light olefins, in practice only some of them are used. This is due to the relatively high cost of most catalysts, complexity of composition and technology for production of catalysts as well as for the gas processing in which these catalysts are used [5, 17]. Silicophosphate and zeolite catalysts have been the most commonly used in the oligomerization. Silicophosphate catalysts possess several draw-backs such as high pressure required for processing (up to 10 MPa), short service life of the catalyst which is not susceptible to oxidative reactivation. The disadvantages of zeolite catalysts for high temperature oligomerization include fairly short cycle length and the presence of appreciable quantity of aromatic hydrocarbons and heavy still bottoms in products [6-9]. The paper presents research results of author-developed superacid catalysts based on anion-modified metal oxide, mixed heteropolyacids and nanosized nickel powder applied on nanocomposite acid-activated montmorillonite to process light hydrocarbons into the component of fuel blend. It has been determined that synthesized samples of catalysts have high activity indices in oligomerization of propane-propylene fraction and in alkylation of isobutane with butane-butylene fraction. The most large-capacity process of gas conversion process for light hydrocarbons such as natural, oil-associated and refinery gases is catalytic refining based on the alkylation processes and oligomerization. In spite of the fact that a large variety of catalytic agents find application in the oligomerization of light olefins, in practice only some of them are used. This is due to the relatively high cost of most catalysts, complexity of composition and technology for production of catalysts as well as for the gas processing in which these catalysts are used [5, 17]. Silicophosphate and zeolite catalysts have been the most commonly used in the oligomerization. Silicophosphate catalysts possess several draw-backs such as high pressure required for processing (up to 10 MPa), short service life of the catalyst which is not susceptible to oxidative reactivation. The disadvantages of zeolite catalysts for high temperature oligomerization include fairly short cycle length and the presence of appreciable quantity of aromatic hydrocarbons and heavy still bottoms in products [6-9]. The paper presents research results of author-developed superacid catalysts based on anion-modified metal oxide, mixed heteropolyacids and nanosized nickel powder applied on nanocomposite acid-activated montmorillonite to process light hydrocarbons into the component of fuel blend. It has been determined that synthesized samples of catalysts have high activity indices in oligomerization of propane-propylene fraction and in alkylation of isobutane with butane-butylene fraction.