• Journal of the Korean Chemical Society
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• v.25 no.1
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• pp.26-29
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• 1981

Reactions of m-xylene were studied in a fixed-bed type micropulse reactor over cation-exchanged dealuminated mordenite and zeolite Y catalysts. Over H-mordenite catalysts higher catalyst pretreatment temperature as well as dealumination resulted in the increase of the formation of disproportionation product. $Ba^{2+}- and Mg^{2+}-$exchanged mordenite catalysts showed the shape selectivity in the disproportionation reaction of m-xylene, that is, the formation of trimethylbenzene decreasing sharply as the degree of cation exchange increased.

• Clean Technology
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• v.14 no.2
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• pp.87-94
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• 2008

The catalytic properties of large pore zeolite (mordenite, beta, and Y) with 12-membered rings were comparatively evaluated in the synthesis of diethylamines from ethanol amination. The number of strong acid sites, which obviously promoted the formation of mono- and diethylamines, was decreased with the increase of Si/Al ratio of the zeolites that were used. H-beta and H-Y zeolites with multidimensional pore channels favorably formed diethylether by the dimerization of ethanol, due to their large cage volumes and low acid strength. On the other hand, H-mordenite which has one dimensional straight channel was shown to be suitable for the formation of mono- and diethylamine which are well known as the useful intermediates of fine chemicals.

• Applied Chemistry for Engineering
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• v.23 no.3
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• pp.320-325
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• 2012

The catalytic cracking of waste lubricant oil was carried out on silica-alumina (SA), hydrogen-type mordenite (HM), and dealuminated mordenite (DM) with the silica/alumina ratio of 10.5, 10, and 12.5, respectively. Activity in the catalytic cracking was found to be in the order of SA > DM > HM. Carbon number distribution of the oil obtained over SA was similar to that of gasoline while that of the oil obtained over DM was similar to that of diesel. Carbon number distribution of the oil obtained over HM was similar to that between gasoline and diesel. Acid amounts of three kinds of catalysts were found to be in the order of $SA\;{\approx}\;HM$ > DM. Unlike HM and DM with pores of an uniform diameter below 10 A, SA had a pore size distribution within the range of 10 to 50 A. These results indicate that the acid amount and pore size of the catalysts may be related to the carbon number distribution of the cracked oil. The decrement of surface area by the accumulation of carbon and impurities on the surface of the catalyst was found to be in the order of SA > DM > HM.

• Journal of the Korean Chemical Society
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• v.37 no.3
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• pp.317-326
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• 1993

The acid catalytic reactions of toluene with n-propylalcohol were investigated and the adsorption experiments of dialkylbenzene isomers were carried out at 100$^{\circ}C$ over modified HZSM-5 zeolites. ZSM-5 zeolite was synthesized by the hydrothermal reaction using 4-propylammonium ion, sodium aluminate and colloidal silica etc., and several zeolite catalysts, including H-, K-, Sr-, P-Mg-HZSM-5, H-Y and H-mordenite, were prepared by conventional methods. The main reaction products of toluene with n-propylalcohol over HZSM-5 catalyst include not only xylenes, propyltoluenes, but also ethyltoluenes and high para-selectivity among dialkylbenzene isomers was observed on P-Mg-HZSM-5 zeolite. The diffusion coefficients of various p-dialkylbenzenes are nearly the same, about 1 ${times}$ 10$^{-10}$ cm$^2$/sec and that of m-xylene was about one tenth of o-xylene. These reaction and adsorption characteristics were interpreted in the light of the shape-selectivity related to related to the zeolite pore structure and the zeolitic acidity.