Zmiany powierzchniowych i strukturalnych właściwości węgli aktywnych wywołane ich utlenianiem

• Autorzy: Choma J. , Jaroniec M. , Burakiewicz-Mortka W. , Klinik J. , Tybel A.

Warianty tytułu

EN

Oxidation-induced changes in the surface and structural properties of active carbons

• Języki publikacji: PL

Abstrakty

EN

The objective of the study was to investgate how liquid-phase oxidation with H2O2, HClO4 or HNO3 affects the surface and structural properties of active carbons. To evaluate structural prperties use was made of low-temperature-(-196oC)experimental adsorption isotherms of nitrogen measured on unimodified and oxidized carbons.Experimental adsorption isotherms of water vapor ( measured on unimodified and oxidized active carbons at 25o C )were used to determine surface properties.The oxidation process was fuond to influence the parameters the porous structure.This influence was particularly distinct when the samples were oxidized with HNO3at its boiling temperature.The oxidation process also changed the surface properties of the carbons,thus increasing the amount of adsorbed water vapor.In strongly oxidized active carbons samples a change in the adsorption mechanism was observed ( as compared to unmodified or weakly oxidized samples).This observation was confirmed quantitatively by the parameters of the adsorption equations which were used to describe the experimental isotherms.The oxygen groups that form in the course of the oxidation process were fund to alter the mechanism governing water phase formation on the carbon surface.This is reflected by the substantial changes in the adsorption potential distributions due to progressive oxidation of the carbon surface.

Słowa kluczowe

PL

absorbent węglowy; węgle aktywne; utlenianie; właściwości węgli aktywnych

• Wydawca: Polskie Zrzeszenie Inżynierów i Techników Sanitarnych, Oddział Dolnośląski
• Czasopismo: Ochrona Środowiska
• Rocznik: 1998
• Tom: nr 3
• Strony: 13--20
• Opis fizyczny: Bibliogr. 17 poz.,rys.,tab.,wykr.

Twórcy

autor

Choma J.

• WAT Warszawa

autor

Jaroniec M.

• Kent State University, Ohio, USA

autor

Burakiewicz-Mortka W.

• WAT Warszawa

autor

Klinik J.

• AGH Kraków

autor

Tybel A.

• WAT Warszawa

Bibliografia

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