Modification of activated carbons for application in adsorption cooling systems
Eliza Wolak
Elżbieta Vogt
Jakub Szczurowski
Abstract
In this paper commercially available activated WD-extra carbon (Gryfskand) which is applied for water treatment was used. Activated carbon was modified by the following chemical agents: H2O2, HNO3 and HCl. Chemical modifications significantly affect the chemical, structural and surface properties of activated carbons. Hydrophobization with ethereal stearic acid was performed on the raw material and samples after chemical modification. Hydrophobic properties of the samples were specified. The relationship of the chemical modification agents with hydrophobization degree was indicated. The thermal effects of wetting by methanol was measured. The heat of wetting was calculated. The purpose of the work was to modify the WD carbon properties to obtain an adsorbent for cooling systems characterized by both good thermal capacity and moisture resistance. The modifying chemical substances applied accounted for an increase in the concentration of the acid functional groups. The hydrophobized and HCl-modified WD(HCl) carbon has the best hydrophobized properties. The results of studies describing such modifications allow to conclude that the use of hydrophobic materials may lead to the production of sorbents with new functions facilitating their storage and use.
Keywords:
activated carbon, hydrophobization, modification, heat of wettingReferences
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