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Biotechnology and Bioprocess Engineering 17: 862-874 (2012) DOI 10.1007/s12257-011-0614-5
RESEARCH PAPER
Adsorption of Methylene Blue Using Green Pea Peels (Pisum sativum): A Cost-effective Option for Dye-based Wastewater Treatment
Ramesh Dod, Goutam Banerjee, and S. Saini
Received: 23 November 2011 / Revised: 24 March 2012 / Accepted: 3 April 2012 The Korean Society for Biotechnology and Bioengineering and Springer 2012
Abstract Methylene blue (MB), a common toxic dye, is largely discharged from dyeing processes for acrylic, nylon, silk, and woolen fabrics in textile industries. While application of conventional removal processes like chemical precipitation, ion exchange, commercial activated carbon adsorption, etc often become cost-prohibitive, the adsorption of MB by abundantly available green pea peel (GPP: Pisum sativum) derived and acid-treated carbon (GPP-AC) has proved to be a cost-attractive option in the present study. The physicochemical and morphological characteristics of GPP-AC were examined with the help of XRD, BET surface area, SEM, and Fourier transform infrared spectrophotometry ((FT-IR) analysis. The influences of such adsorption parameters as initial dye concentration, pH, contact time, adsorbent dosage, agitation speed, particle size, and temperature were evaluated and optimized. The equilibrium contact time for maximum adsorption of MB on to GPPAC was found to be 7 h. The equilibrium data of the adsorption process were modeled by using the Langmuir, Freundlich, Temkin, and Dubinin-Raduskevich (D-R) isotherms. However, the adsorption equilibrium data were best described by the Langmuir Isotherm model, with a maximum adsorption capacity of 163.94 mg MB/g GPPAC at 30oC.
Keywords: adsorption, Dubinin-raduskevich, Freundlich, green peas peels, isotherms, Langmuir, methylene blue, Temkin
1. Introduction
Methylene blue (MB), which is a cationic basic dye, is primarily used for acrylic, nylon, silk, and wool dyeing in the textile industries. In general, about 10 ~ 15% of the used dye is lost in the effluent of textile units.
Basic dyes like MB are reported to cause allergic dermatitis, skin irritation, cancer, and mutations [1]. MB can cause eye burns which may be responsible for permanent injury to the eyes of human and animals. On inhalation, it can give rise to short periods of rapid or difficult breathing while ingestion through the mouth produces a burning sensation and may cause nausea, vomiting, profuse sweating, mental confusion and methanoglobinemia [2]. Therefore, removal of dyes from the effluent...