Kaolin-issued zeolite A as efficient adsorbent for Bezanyl Yellow and Nylomine Green anionic dyes

• Published in: Microporous and mesoporous materials 2017-05, Vol.243, p.91-101
• Main Authors: Fardjaoui, Nor-El-Houda, El Berrichi, Fatima Zohra, Ayari, Faouzi
• Format: Article
• Language: English
• Subjects: Bezanyl Yellow; DD3; Nylomine Green; Topological polar surface areas (TPSA); Zeolite A
• ISSN: 1387-1811; 1873-3093
• DOI: 10.1016/j.micromeso.2017.01.008

Zeolite A was synthesized by the autoclave method in alkaline medium using the DD3 Algerian clay, and then characterized by SEM, XRF, N2 physisorption at −196 °C, and XRD. In the temperature range 25–60 °C, the synthesized zeolite A can be efficiently used for Bezanyl Yellow (BY) and Nylomine Green (NG) adsorption (25 mg L−1) at very low adsorbent doses (5× 10−4 g zeolite Agsolution−1) and neutral pH (∼7). The changes of free energy (ΔG°), enthalpy (ΔH°), and entropy (ΔS°) during physisorption were carefully evaluated. On the other hand, Freundlich isotherm and pseudo–second–order kinetics were found to be the most appropriate models to describe the endothermic physisorption of BY (Ea = 23.4 ± 1 kJ mol−1) and NG (Ea = 18.34 kJ mol−1). The synthesized zeolite A exhibited superior adsorption capacities and percentages of anionic dyes removal compared to DD3, bentonite and commercial zeolite A. [Display omitted] •DD3 Algerian kaolin is used as starting material for the synthesis of zeolite A.•The removal of Bezanyl Yellow and Nylomine Green is efficient over zeolite A.•The synthesized zeolite A is more efficient in adsorption than the commercial one.