Effects of regeneration conditions on the characteristics of water vapor adsorption on silica gel

Adsorption and diffusion of water vapor in phosphonium ionic liquid modified silica gel were studied, aiming to reduce the loading of water vapor in porous materials. The modified silica gel was prepared through a grafting method and characterized by FTIR, thermal gravity analysis and X-ray photoelectron spectroscopy. N2 sorption isotherms at −196 °C and CO2 sorption isotherms at 0 °C were also measured to analyzee the porosity. Water vapor adsorption equilibriums at 25 °C up to 30 mbar were tested. The results indicate that the ionic liquids (ILs) phase acts as a protecting film which decreases water vapor adsorption. The improvement of water-resistant performance is also attributed to the decrease of micro-porosity and silanol groups on the silica surface. Diffusion behavior of water vapor on modified silica was determined on the basis of the adsorption equilibrium. The effective diffusivity of water vapor in modified silica is almost the same as in bare silica and decreases with the increasing of water vapor loading.

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Simulation of Water Vapor Adsorption in a Fixed-bed Column with Silica Gel Material for Thermal Energy Storage Applications

Proceedings of the International Conference on Fluid Flow and Thermal Science (ICFFTS'20) ◽

10.11159/icffts20.128 ◽

2020 ◽

Author(s):

Ye Carrier ◽

Curtis Strong

Keyword(s):

Water Vapor ◽

Energy Storage ◽

Silica Gel ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Fixed Bed ◽

Water Vapor Adsorption ◽

Fixed Bed Column ◽

Vapor Adsorption ◽

Energy Storage Applications

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Enhancement mechanisms of water vapor adsorption rate onto silica-gel in acoustic field

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2019.119088 ◽

2020 ◽

Vol 148 ◽

pp. 119088

Author(s):

Junpei Fujiki ◽

Masayuki Nakayama ◽

Yuki Ueda ◽

Atsushi Akisawa

Keyword(s):

Water Vapor ◽

Silica Gel ◽

Acoustic Field ◽

Water Vapor Adsorption ◽

Adsorption Rate ◽

Vapor Adsorption

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Near-IR Spectroscopic Examination of Thin-Layer Chromatography Plates in the Diffuse Transmittance Mode

Applied Spectroscopy ◽

10.1366/0003702944028317 ◽

1994 ◽

Vol 48 (3) ◽

pp. 394-399 ◽

Cited By ~ 8

Author(s):

Andrew Fong ◽

Gary M. Hieftje

Keyword(s):

Water Vapor ◽

Thin Layer ◽

Thin Layer Chromatography ◽

Silica Gel ◽

Water Vapor Adsorption ◽

Infrared Spectrometry ◽

Calibration Model ◽

Vapor Adsorption ◽

Near Ir ◽

Layer Chromatography

The nondestructive detection of analyte spots on high-performance thin-layer chromatography (HPTLC) plates is demonstrated with the use of near-IR spectrometry (NIRS). The resulting hyphenated technique is called Thin-Layer Chromatography-Near-Infrared Spectrometry (TLC-NIRS). A transmittance geometry is employed, and a set of 18 interference filters is used for wavelength selectivity. Plate-thickness nonuniformity and varying amounts of water vapor adsorption onto the silica-gel TLC plates were found to be the major complications. Variations in silica-gel thickness could be compensated for by obtaining reference spectral scans of the HPTLC plates before performing the chromatography. The effects of water-vapor adsorption were reduced through use of a partial least-squares calibration model. Detection limits near 1 μg were obtained.

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