Acid and catalytic properties of new thermostable sulfocationic exchangerssupported on aluminosilicates

The acid properties of supported polyphenylketone and sulfopolyphenylketone were followed by quantitative IR studies of ammonia and pyridine adsorptio n. The deposition of polyphenylketone decreased the concentration of Bronst ed acid sites and also diminished the intensity of TR band of silanol (Si-O H) groups, due to partial covering of aluminosilicate surface by polymer. S ulfonation of supported polyphenylketone (by H2SO4 treatment) resulted in a distinct increase of Bronsted acidity, because of SO3H groups insertion. T he amount of new protonic sites was lower than the amount of sulfur atoms i nserted by sulfonation, which indicated that not all sulfur atoms took part of acidic SO3H groups. The conversion in 2-propanol dehydration showed the same trends as the Bronsted acidity of the samples. The dehydration activi ty of aluminosilicate supports decreased upon polyphenylketone deposition a nd distinctly increased upon sulfonation. 2-Propanol dehydration produced p ropene and diisopropyl ether (DIPE). The selectivity of supports towards DI PE was 31-48%. It increased upon polyphenylketone deposition and sulfonatio n (to 65-77%). Supported sulfopolyphenylketone may be efficient catalysts f or the production of DIPE (which may be high octane, oxygen containing addi tive to fuels). The advantage of supported sulfopolyphenylketones, comparin g with unsupported acidic cationites (e.g. sulfonated styrene-divinylbenzen e copolymers) are: possibility of formation of big grains, large surface ar ea, high thermal and mechanical stability, as well as not swelling in react ion media. (C) 1999 Elsevier Science B.V. All rights reserved.