Molecular Dynamics Study on the Effect of Surface Hydroxyl Groups on Three-Phase Wettability in Oil-Water-Graphite Systems

We have studied the adsorption of the four isomers of butanol on silicalite and on H-ZSM-5 using an energy minimization procedure supplemented by a Monte Carlo/molecular dynamics algorithm to assist in the location of minima. The energetics and the geometries of adsorption of the butanol isomers in the pores of silicalite and H-ZSM-5 are reported. The effect of the relaxation of both the adsorbent framework and of the adsorbate molecule is investigated. Significant changes in the direction of the surface hydroxyl groups at certain crystallographic positions are induced by alcohol physisorption. For both silicalite and H-ZSM-5, similar energy values were obtained for each butanol isomer sorbed at a number of different crystallographic positions. We therefore predict that there are a range of physisorbed states for all butanols at ambient temperatures. The small variations in the adsorption energetics and sites between isomers may be explained in the terms of pore-confinement effects on the adsorption of molecules with dimensions similar to those of pentasil channels.

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Effect of activation temperature on acidity of alumina, silica-alumina and cobalt-molybdenum-alumina catalysts

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19851268 ◽

1985 ◽

Vol 50 (6) ◽

pp. 1268-1273 ◽

Cited By ~ 3

Author(s):

Zdeněk Vít

Keyword(s):

Acid Sites ◽

Hydroxyl Groups ◽

Activation Temperature ◽

Cumene Cracking ◽

Surface Hydroxyl ◽

Catalytic Activities ◽

Surface Hydroxyl Groups ◽

Silica Alumina ◽

Effect Of Surface ◽

Alumina Catalysts

The effect of surface dehydration on the acidity of silica-alumina and cobalt-molybdenum-alumina catalysts has been studied and compared with alumina. The catalysts were characterized by surface hydroxyl groups concentrations, acid sites concentrations and by catalytic activities in paraldehyde depolymerisation and cumene cracking. It was found that the acidity of alumina and cobalt-molybdenum-alumina catalysts increases significantly with surface dehydration and attains maximum after activation at 500-550 °C. Silica-alumina is strongly acidic even in the hydrated state, the acidity being formed already at relatively low temperature around 100 °C.

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Effect of surface hydroxyl groups on the dispersion of ceramic powders

Materials Chemistry and Physics ◽

10.1016/j.matchemphys.2016.01.060 ◽

2016 ◽

Vol 172 ◽

pp. 1-5 ◽

Cited By ~ 8

Author(s):

Tse-Hsing Ho ◽

Shinn-Jen Chang ◽

Chia-Chen Li

Keyword(s):

Hydroxyl Groups ◽

Ceramic Powders ◽

Surface Hydroxyl ◽

Surface Hydroxyl Groups ◽

Effect Of Surface

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The Effect of Surface Hydroxyl Groups on the Properties of SR/Al2O3 Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.66.277 ◽

2009 ◽

Vol 66 ◽

pp. 277-279 ◽

Cited By ~ 1

Author(s):

Yuan Lu Xiong ◽

Qiang Shen ◽

Fei Chen ◽

Jin Zheng ◽

Lian Meng Zhang

Keyword(s):

Heat Treatment ◽

Flexural Strength ◽

Relative Density ◽

Heat Treatment Temperature ◽

Treatment Temperature ◽

Hydroxyl Groups ◽

Surface Hydroxyl ◽

Surface Hydroxyl Groups ◽

Sandy Alumina ◽

Effect Of Surface

SR/Al2O3 composites were fabricated from different heat treatment temperatures of alumina. The results show that the relative density is over 94% and flexural strength is 66.5MPa when silicone content is 33wt.%. The flexural strength of the obtained SR/Al2O3 composites is decreased when increasing the heat treatment temperature of sandy alumina, indicating that the surface hydroxyl groups directly influence the flexural strength of SR/Al2O3 composites.

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