Ethanol dehydration on alumina catalysts II. The infrared study on adsorption of diethyl ether over alumina
1968; Elsevier BV; Volume: 10; Issue: 2 Linguagem: Inglês
10.1016/0021-9517(68)90164-4
ISSN1090-2694
Autores Tópico(s)Catalysis for Biomass Conversion
ResumoThe structure and thermal decomposition products of diethyl ether adsorbed on alumina have been studied by infrared spectroscopy and mass spectrometry. It was confirmed by infrared spectroscopy that two kinds of surface compounds were formed at different temperature ranges, when dehydrated alumina was exposed to diethyl ether vapor: a coordination complex, (C2H5)2OAl<, below 100 °C and a surface ethoxide, C2H5OAl<, above 100 °C. The coordination complex was thermally decomposed below 130 °C, giving a mixture of ethanol, diethyl ether and ethylene, whereas above 130 °C more than 97% of the adsorption complex was recovered as ethylene. Correspondingly, the surface ethoxide, which had been made by adsorption at 130 °C, was 97% desorbed at 210 °C as ethylene. A reaction scheme for the dehydration of ethanol on alumina catalyst is discussed on the ground of these results. For the adsorption of diethyl ether on silica gel, a hydrogen bonding interaction between the oxygen atom of diethyl ether and the surface silanol group was recognized by infrared spectroscopy.
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