title: Adsorption of basic dyes in single and mixture systems on granular inorganic-organic pillared clays.
abstract: The adsorption of two basic dyes, CI Basic Yellow 28 and CI Basic Green 4, was studied in single and binary solute systems using two classes of inorganic-organic pillared clay granules as sorbents (300-400 microm and 700-800 microm). These were prepared by high-shear wet granulation from an Al cetyltrimethylammonium bromide intercalated clay powder (particle diameter < 50 microm). Adsorption rate data indicate that BY 28 adsorbs more rapidly than BG 4 and a pseudo-first-order model was found to fit the kinetic curves, with regression coefficients above 0.98. Adsorption isotherms in single solute systems at pH 3 and pH6 were respectively analysed according to the Langmuir and Freundlich models using non-linear regression. Best fits were obtained with the Langmuir model. In binary dye systems the adsorption at three molar ratios (1:9, 1:1 and 9:1) demonstrated that the adsorption of BG 4 was greater than that of BY 28 on all the sorbents studied; this was in agreement with the results obtained for single solute systems. Increasing the granule size decreased dye adsorption, an effect in accordance with the Sheindorf-Rebuhn-Sheintuch model.
authors.affiliation: Groupement de Recherche Eau Sol Environnement (EA 4330), Université de Limoges, 123 avenue Albert Thomas, 87060 Limoges, France.
authors.forename: Benamar
authors.initials: B
authors.lastname: Cheknane
authors.forename: Michel
authors.initials: M
authors.lastname: Baudu
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Basly
authors.forename: Omar
authors.initials: O
authors.lastname: Bouras
mesh_terms: D000042:Absorption; D000538:Aluminum Silicates / Q000737:chemistry*; D000077215:Clay; D004396:Coloring Agents / Q000737:chemistry* / Q000302:isolation & purification*; D045424:Complex Mixtures / Q000737:chemistry; D007287:Inorganic Chemicals / Q000737:chemistry; D009930:Organic Chemicals / Q000737:chemistry; D011208:Powders; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
chemical_list: D000538:Aluminum Silicates; D004396:Coloring Agents; D045424:Complex Mixtures; D007287:Inorganic Chemicals; D009930:Organic Chemicals; D011208:Powders; D014874:Water Pollutants, Chemical; D014867:Water; D000077215:Clay