S. N. Khadzhiev

Effect of hydrothermal treatment on catalytic properties of superhigh-silica zeolites

The effect of hydrothermal treatment of decationized superhigh-silica zeolite on the mechanism of n-hexane conversion has been studied. It has been established that thermosteam modification sharply decreases the cracking activity and increases the selectivity to aromatization reactions. Zeolite acidity markedly decreases, but its crystal structure does not become amorphous.AbstractИзучено влияние термопаровой обработки декатионированной формы сверывысококремнеземного цеолита на закономерности превращения н-гексана. Термоларовое модифицирование приводит к резкому падению крекирующей активности и повышению селективности в реакциях ароматизации. При этом наблюдается значительное снижение кислотности цеолита без заметной аморфизации кристаллической структуры.

Operating experience with unit for sulfuric acid alkylation of isobutane by butylenes

The operation of units for the sulfuric acid alkylation of isobutanes by butylenes have been performed. The reaction was carried out in a KSG-3 horizontal sulfuric acid contractor. A butane-butylene fraction from catalytic cracking and an isobutane fraction from the central gas fractionating unit were used as a feedstock. The studies have shown that the unit will give a high-quality product under various conditions of operation. The specific consumption of sulfuric acid in processing different types of feed remains within acceptable limits.

Catalytic properties of initial and thermosteamed faujasites in n-hexane aromatization

Regularities in n-hexane conversion on decationized Y zeolites under cracking and aromatization conditions have been studied. Possible formation of lower olefins and benzenes in parallel reactions following different mechanisms at low conversion degrees is suggested. The effect of thermosteam treatment on the activity and selectivity of Y zeolites in n-hexane conversion has been examined.AbstractИзучены закономерности превращения н-гексана на декатионированной форме цеолита Y в условиях крекинга и ароматизации. В области малых конверсий показана возможность образования низкомолекулярных олефинов и бензола в параллельных реакциях, протекающих по различным механизмам. Исследовано влияние термопаровой обработки на активность и селективность цеолита Y в превращении н-гексана.

CATALYTIC AND ACIDIC PROPERTIES OF DIFFERENT METAL-ZEOLITE CATALYSTS

Catalytic and acidic properties of bifunctional catalysts containing faujasite, superhigh-silica zeolite and mordenite have been studied in isomerization of C8-alkylaromatic hydrocarbons.AbstractВ реакции изомеризации алкилароматических углеводородов C8 изучены каталитические и кислотные свойства бифункциональных катализаторов, содержащих фожазит, сверхвысоко-кремнеземный цеолит и морденит.

New unit for sulfuric acid alkylation of isobutane by olefins

The authors describe and illustrate a sulfuric acid alkylation unit with a horizontal contact. As a result of the use of this design solution, the isobutane/olefin ratio is 10/1 in comparison with 4/1 to 5/1 in the other types of units, namely vertical reactors and cascade tank reactors. The unit was designed to process the butane-butylene cut (BBC) and part of the propane-propylene cut (PPC) from the G-43-107 cat cracker. The unit design includes provisions for controlled caustic washing of the feed and dehydration in an electric field. The authors present the basic data obtained in the three months of unit operation after startup, in comparison with the operating indexes of a sulfuric acid alkylation unit.

Influence of the molar ratio SiO2∶Al2O3 in super-high silica zeolite on the acidic and catalytic properties of palladium catalysts in isomerization of C8 aromatic hydrocarbons

The effect of the molar ratio SiO2∶Al2O3 in the high-silica zeolite on the catalytic properties of palladium catalysts in the isomerization of m-xylene and ethylbenzene has been studied. A correlation between catalytic and acidic properties of the samples examined is suggested.AbstractПредставлены экспериментальные данные по влиянию молярного отношения окислов кремния и алюминия в сверхвысококремнеземном цеолите на каталитические свойства палладиевых катализаторов в реакции изомеризации м-ксилола и этилбензола. Получена корреляция каталитических и кислотных свойств изученных образцов.