Removal of Cr(VI) from aqueous solutions by using activated carbon supported iron catalysts as efficient adsorbents. (12th February 2018)

• Record Type: Journal Article
• Authors: Derdour, Karima; Bouchelta, Chafia; Khorief Naser-Eddine, Amina; Medjram, Mohamed Salah; Magri, Pierre
• Is Part Of: World journal of engineering. Volume 15:Number 1(2018)
• Page Start: 3
• Page End: 13
• Publication Date: 2018-02-12
• Subjects: Adsorption -- Activated carbon -- Hexavalent chromium -- Iron catalysts -- Walnut shell -- Wetness impregnation; Engineering -- Periodicals; 620
• DOI: 10.1108/WJE-06-2017-0132
• Languages: English
• ISSNs: 1708-5284

Abstract

Abstract : Purpose: The purpose of this paper is to focus on the removal of hexavalent chromium [Cr(VI)] from wastewater by using activated carbon-supported Fe catalysts derived from walnut shell prepared using a wetness impregnation process. The different conditions of preparation such as impregnation rate and calcination conditions (temperature and time) were optimized to determine their effects on the catalyst's characteristics. Design/methodology/approach: The catalyst samples were characterized using thermogravimetric analysis, scanning electron microscopy and Fourier transform infrared spectroscopy. The adsorption of Cr(VI) by using using activated carbon supported Fe catalysts derived from walnut shell as an adsorbent and catalyst was investigated under different adsorption conditions. The parameters studied were contact time, adsorbent dose, solution pH and initial concentrations. Findings: Results showed that higher adsorption capacity and rapid kinetics were obtained when the activated walnut shell was impregnated with Fe at 5 per cent and calcined under N2 flow at 400°C for 2 h. The adsorption isotherms data were analyzed with Langmuir and Freundlich models. The better fit is obtained with the Langmuir model with a maximum adsorption capacity of 29.67 mg/g for Cr(VI) on Fe5-AWS at pH 2.0. Originality/value: A comparison of two kinetic models shows that the adsorption isotherms system is better described by the pseudo-first-order kinetic model.