ADSORPTION BEHAVIOUR OF IONIC AND NON-IONIC SURFACTANTS ONTO TALC A NATURALLY HYDROPHOBIC MINERAL-A COMPARATIVE STUDY

Authors : Sedef DİKMEN, Bahri ERSOY, Zafer DİKMEN

Pages : 139-152

Doi:10.18038/estubtda.829712

View : 35 | Download : 14

Publication Date : 2020-11-27

Article Type : Research Paper

Abstract :In present study, the adsorption behaviour of surfactants which are cationic insert ignore into journalissuearticles values(hexadecyltrimethylammonium bromide, HTAB);, anionic insert ignore into journalissuearticles values(sodium dodecyl sulphate, SDS); and non-ionic insert ignore into journalissuearticles values(Triton X-100, TX-100); onto naturally hydrophobic talc were investigated. In this scope, a series of batch adsorption tests at natural pH were performed to determine adsorption isotherms and zeta potential insert ignore into journalissuearticles values(ZP); measurements of the ionic and non-ionic surfactants onto talc surfaces were measured using electrophoresis technique. To understand the mechanism of the adsorption process, the adsorption of ionic and non-ionic surfactants was studied as a function equilibrium concentration insert ignore into journalissuearticles values(mol/L);. The amount of maximum adsorption of the surfactants onto talc are ordered as in the following: TX-100 insert ignore into journalissuearticles values(9.0x10-5 mol/m2);>HTAB insert ignore into journalissuearticles values(8.5x10-5 mol/m2); > SDS insert ignore into journalissuearticles values(5.32x10-5 mol/m2);. Even though both the SDS and talc have negative surface charge, SDS can adsorb onto talc. Moreover, a good correlation was seen between the adsorption isotherms and the zeta potential curves. Considering their adsorption isotherms, the ionic surfactants were showed different adsorption behaviour concerning the non-ionic surfactant molecules. The adsorption isotherms of TX-100 and SDS increase rapidly in a narrow concentration range until the plateau region, while such a sharp increase does not appear for HTAB. The maximum adsorption amount of TX-100 and HTAB is greater than SDS. The results indicate that hydrophobic interaction and hydrogen bonding play a decisive role on the adsorption of non-ionic and anionic surfactants onto talc a naturally hydrophobic mineral, whereas electrostatic interaction becomes more important in the adsorption of cationic surfactant.
Keywords : Talc, Surfactant, Adsorption, FT IR, Zeta Potential

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