Methods to quantify contamination effects on silica gel samples

Technical Report · Mon Sep 01 04:00:00 EDT 1986

OSTI ID:5115541

Pesaran, A A; Thomas, T M; Penney, T R; Czanderna, A W

This report describes a study to establish methods for measuring sorption degradation of contaminated solid desiccants and determining the identity and nature of the contaminants. A literature search was conducted to determine how contaminants affect the sorption properties of silica gel and advanced solid desiccant materials; the search yielded 73 papers. Silica gel was chosen for the contamination study; nine samples from various batches and suppliers were tested. Methods were established (1) to measure the degradation of desiccant adsorption capacity caused by regeneration processes and/or exposure to contaminants and (2) to determine the nature of these contaminants. Sorption measurements on a limited number of fresh silica gel samples showed that the water adsorption capacity varied about +-10%. The silica gel sample regenerated with electric heaters exhibited a maximum capacity degradation of 7%. Silica gel samples processed in other ways lost between 20% and 47% capacity, depending on the age and cycle of regeneration. The contaminants found were silicon, oxygen, carbon, and nitrogen using x-ray photoelectron spectroscopy. Contamination can degrade the water sorption capacity of desiccants.

• Research Organization: Solar Energy Research Inst., Golden, CO (USA)
• DOE Contract Number: AC02-83CH10093
• OSTI ID: 5115541
• Report Number(s): SERI/TR-252-2802; ON: DE86014504
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140901* -- Solar Thermal Utilization-- Space Heating & Cooling
36 MATERIALS SCIENCE
360603 -- Materials-- Properties
ADSORBENTS
CARBON
CONTAMINATION
DESICCANTS
ELECTRON SPECTROSCOPY
ELEMENTS
NITROGEN
NONMETALS
OXYGEN
PHOTOELECTRON SPECTROSCOPY
SEMIMETALS
SILICA GEL
SILICON
SORPTIVE PROPERTIES
SPECTROSCOPY
SURFACE PROPERTIES
TESTING