A Novel Biosorbent, Water-Hyacinth, Uptaking Methylene Blue from Aqueous Solution: Kinetics and Equilibrium Studies

Sreejon Das,Md Nasir Uddin,Md Tariqul Islam

doi:10.1155/2014/819536

Sreejon Das, Md Nasir Uddin + Show 1 more

Open Access

https://doi.org/10.1155/2014/819536

Copy DOI

Abstract

The adsorption of MB dye from aqueous solution onto HCl acid treated water-hyacinth (H-WH) was investigated by carried out batch sorption experiments. The effect of process parameters such as pH, adsorbent dosage, concentrations and contact time, and ionic strength were studied. Adsorption of MB onto H-WH was found highly pH dependent and ionic strength shows negative impact on MB removal. To predict the biosorption isotherms and to determine the characteristic parameters for process design, Langmuir, Freundlich, Temkin, and Halsey isotherms models were utilized to equilibrium data. The adsorption kinetics was tested for pseudo-first-order (PFO), pseudo-second-order (PSO), intraparticle diffusion (IPD), and Bangham’s kinetic models. The Langmuir isotherm model showed the goodness-of-fit among the tested models for equilibrium adsorption of MB over H-WH and indicated the maximum adsorption capacity as 63.30 mg/g. Higher coefficient of determination (R2>0.99) and better agreement between the qe (experimental) andqe(calculated) values predicted that PSO kinetic model showed the goodness-of-fit for kinetic data along with rate constant1.66×10-3,4.42×10-3, and3.57×10-3 mg·g-1min⁡-1/2⁡, respectively, for the studied concentration range. At the initial stage of adsorption, the overall rate of dye uptake was found to be dominated by external mass transfer, and afterwards, it is controlled by IPD mechanism.

Highlights

Adsorption is one of the most widely applied techniques for removal of certain classes of chemical pollutants from waters, especially those that are hardly demolished in traditional water-treatment plants [1]
Many great efforts have demonstrated that WH can be used to adsorb a cationic dye [4], phenol [9], cadmium [5], copper [10], uranium (VI) [11], Victoria blue [12], crystal violet [13], and so forth, from aqueous solution
It is seen that the trends of C–O were altered from 1036 cm−1 to 1039.60 cm−1 It is obvious from Figure 1 that MB gave strong spectra at 1580 cm−1, 1420 cm−1, 1376 cm−1, and 650.70 cm−1, respectively

Summary

Introduction

Adsorption is one of the most widely applied techniques for removal of certain classes of chemical pollutants from waters, especially those that are hardly demolished in traditional water-treatment plants [1]. The adsorption process can be taken as an effective alternative for the pollutants uptake from waste water only when the adsorbent is inexpensive and does not need an additional pretreatment before its application [3]. The extent of pollutants uptake by aquatic plant has been extensively tested [4,5,6]. Water-hyacinth (WH), an aquatic plant, has received considerable attention because of its potential to remove pollutants, when used as a biological filtration system [7]. Many great efforts have demonstrated that WH can be used to adsorb a cationic dye (methylene blue, MB) [4], phenol [9], cadmium [5], copper [10], uranium (VI) [11], Victoria blue [12], crystal violet [13], and so forth, from aqueous solution

Objectives

Methods

Results

Conclusion