Effective removal of excessive fluoride from aqueous environment using activated pods of Bauhinia variegata: Batch and dynamic analysis.

Autor: Jayashree DE; Department of Chemical Engineering, Sri Sivasubramaniya Nadar College of Engineering, Chennai, India., Kumar PS; Department of Chemical Engineering, Sri Sivasubramaniya Nadar College of Engineering, Chennai, India; SSN-Centre for Radiation, Environmental Science and Technology (SSN-CREST), Sri Sivasubramaniya Nadar College of Engineering, Chennai, India. Electronic address: senthilchem8582@gmail.com., Ngueagni PT; Department of Chemical Engineering, Sri Sivasubramaniya Nadar College of Engineering, Chennai, India; Laboratoire de Chimie Inorganique Appliquée, Faculté des Sciences, Université de Yaoundé, I. B.P: 812, Yaoundé, Cameroon., Vo DV; Center of Excellence for Green Energy and Environmental Nanomaterials (CE@GrEEN), Nguyen Tat Thanh University, Ho Chi Minh City, Viet Nam., Chew KW; School of Energy and Chemical Engineering, Xiamen University, China.
Jazyk: angličtina
Zdroj: Environmental pollution (Barking, Essex : 1987) [Environ Pollut] 2021 Mar 01; Vol. 272, pp. 115969. Date of Electronic Publication: 2020 Nov 06.
DOI: 10.1016/j.envpol.2020.115969
Abstrakt: In this study, a novel biosorbent is prepared from the pods of Bauhinia variegata is used for defluoridation of the fluoride contaminated water. It is an eco-friendly and economically feasible material. Comparison of adsorption capacity of Physically Treated Bauhinia (PTB) and Chemically Treated Bauhinia (CTB) are carried in this work. Characterization studies like SEM, EDS, FTIR, and XRD are executed to analyze surface morphology and functional groups in PTB and CTB. The experimental procedure was implemented in a batch process where the operating constraints such as dosage, pH, initial fluoride concentration, time, and temperature are varied to attain optimized efficiency. PTB and CTB yield an adsorption capacities of 10.90 mg/g and 15.45 mg/g respectively in the batch process. PTB adheres fluoride in monolayer formation whereas CTB forms multilayer adsorption. The adsorption process was described by the Pseudo first-order model to state the mechanism of physisorption. The negative values of thermodynamic parameters indicate spontaneity and favorable conditions for adsorption process. As CTB has a higher adsorption capacity than PTB, the batch study has been extended to column adsorption. Bed depth, initial fluoride concentration, and flow rate are the experimental variables used to acquire breakthrough curves. Simplified column models like Adam-Bohart, Thomas, and Yoon-Nelson models were analyzed. In column studies, Yoon-Nelson model fitted well in describing the process of adsorption. The maximum adsorption capacity acquired during the column process was found to be 1.176 mg/g with a bed depth of 5 cm and a flow rate of 5 ml/min. Thus, the innocuous and sustainable adsorbent is developed and serves as an excellent defluoridation agent.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2020 Elsevier Ltd. All rights reserved.)
Databáze: MEDLINE
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