For the development of high efficiency porous supports for composite membrane preparation, polysulfone (PSf) hollow fiber membranes (outer diameter 1.57 mm, inner diameter 1.12 mm) were modified by air plasma using the low temperature plasma treatment pilot plant which is easily scalable to industrial level and the Piranha etch (H 2 O 2 + H 2 SO 4 ). Chemical and plasma modification affected only surface layers and did not cause PSf chemical structure change. The modifications led to surface roughness decrease, which is of great importance for further thin film composite (TFC) membranes fabrication by dense selective layer coating, and also reduced water and ethylene glycol contact angle values for modified hollow fibers surface. Furthermore, the membranes surface energy increased two-fold. The Piranha mixture chemical modification did not change the membranes average pore size and gas permeance values, while air plasma treatment increased pore size 1.5-fold and also 2 order enhanced membranes surface porosity. Since membranes surface porosity increased due to air plasma treatment the modified membranes were used as efficient supports for preparation of high permeance TFC membranes by using poly[1-(trimethylsilyl)-1-propyne] as an example for selective layer fabrication.

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A destructive process of hydroisomerization of straight-run 85-185°C gasoline fraction followed by close fractionation of the products into a high-octane low-boiling (-85°C) isocomponent and a fraction with a final BP of 85°C is proposed. The latter is free of benzene-forming hydrocarbons and is submitted to catalytic reforming under mild conditions. Gasoline with octane number 86 (MM) and containing ~51 wt. % of aromatic hydrocarbons, including less than 0.5 wt. % of benzene, is obtained by compounding the isocomponent and the reformate in 25:75 ratio.Stringent requirements as to the content of toxic substances in the exhausts of vehicles dictates the need to alter the composition of the motor fuels -reduce the sulfur and aromatic-hydrocarbon contents, particularly benzene, while simultaneously improving the operational characteristics -an increase in octane number, better vaporability, and a reduction in the difference in the octane number of the gasoline as a whole and the fraction that boils-off to 100°C. This requires serious changes in the procedure used to produce the gasoline components and balance their compounding.Fulfillment of requirements regarding benzene content and the sums of aromatic hydrocarbons in gasoline represents a major problem, since the basic high-octane component of automotive gasolines produced in large part by petroleum refineries is a reformate containing benzene and the sums of the aromatic hydrocarbons in which 7 and 70 wt. % are obtained, respectively. Moreover, the aromatic hydrocarbons are concentrated in the high BP fractions of the reformate. The reformate fraction that boils-off to 100°C has an octane number of 71-73 (MM), and the octane number is therefore distributed nonuniformly with respect to boiling point. Even though the gasoline is evaluated as high-octane on the whole, knocking may be observed during transitional operating regimes of an engine running on this gasoline.