The adsorption of malachite green (MG) on sodium-exchanged kaolinite and on the same clay treated with two widely used deflocculants, sodium hexametaphosphate (NaHMP) and sodium disilicate (NaDIS), was investigated. The results indicate that the deflocculants affect the adsorption process. In particular, DIS treatment increases physisorption, whereas HMP treatment almost completely prevents it. The Frumkin isotherm accurately describes MG adsorption for all of the adsorbents investigated and the Frumkin inter- action parameter is found to be repulsive, in keeping with the cationic nature of the adsorbed species. TheKeywords: temperature dependences of the adsorption constant and the related thermodynamic parameters H◦ adsAdsorption and S◦ ads were also determined and discussed.
Deflocculant effect on the surface properties of kaolinite investigated through malachite green adsorption / Castellini, Elena; Andreoli, Roberto; Malavasi, Gianluca; Pedone, Alfonso. - In: COLLOIDS AND SURFACES. A, PHYSICOCHEMICAL AND ENGINEERING ASPECTS. - ISSN 0927-7757. - ELETTRONICO. - 329:1-2(2008), pp. 31-37. [10.1016/j.colsurfa.2008.06.045]
Deflocculant effect on the surface properties of kaolinite investigated through malachite green adsorption
CASTELLINI, Elena;ANDREOLI, Roberto;MALAVASI, Gianluca;PEDONE, Alfonso
2008
Abstract
The adsorption of malachite green (MG) on sodium-exchanged kaolinite and on the same clay treated with two widely used deflocculants, sodium hexametaphosphate (NaHMP) and sodium disilicate (NaDIS), was investigated. The results indicate that the deflocculants affect the adsorption process. In particular, DIS treatment increases physisorption, whereas HMP treatment almost completely prevents it. The Frumkin isotherm accurately describes MG adsorption for all of the adsorbents investigated and the Frumkin inter- action parameter is found to be repulsive, in keeping with the cationic nature of the adsorbed species. TheKeywords: temperature dependences of the adsorption constant and the related thermodynamic parameters H◦ adsAdsorption and S◦ ads were also determined and discussed.
Pubblicazioni consigliate
I metadati presenti in IRIS UNIMORE sono rilasciati con licenza Creative Commons CC0 1.0 Universal, mentre i file delle pubblicazioni sono rilasciati con licenza Attribuzione 4.0 Internazionale (CC BY 4.0), salvo diversa indicazione.
In caso di violazione di copyright, contattare Supporto Iris
