INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 1, No 7, 2011 © Copyright 2010 All rights reserved Integrated Publishing Association Research article
ISSN 0976 – 4402
Dye removal from aqueous solution using low cost adsorbent Velmurugan .P 1 , Rathina kumar.V 2 , Dhinakaran.G 3 1 JRF, School of Civil Engineering, SASTRA University, Tamil Nadu, India 2 Assistant Professor, School of Civil Engineering, SASTRA University, Tamil Nadu, India 3 Professor, School of Civil Engineering, SASTRA University, Tamil nadu613 401, India
[email protected] ABSTRACT The use of cheap and ecofriendly adsorbents studied as an alternative substitution of activated carbon for removal of dyes from wastewater. Adsorbents prepared from orange peel, which is a domestic waste, successfully used to remove the methylene blue from an aqueous solution in a batch wise column. This study investigates the potential use of orange peel, pretreated with nominal treatment method, for removal of methylene blue from simulated wastewater. Treated orange peel used to adsorb methylene blue at varying dye concentration, adsorbent dosage, pH and contact time. Similar experiments conducted with some other low cost adsorbent such as banana peel, neem leaves and commercially available powdered activated carbon (PAC). The adsorption capacity of orange peels decreased in the order of methyl orange (MO) > methylene blue (MB) > Rhodamine B (RB) > Congo red (CR) > methyl violet (MV) > amido black 10B (AB). Removal efficiency of all the adsorbents is quite effective, but orange peel found to be very effective compared to other low cost adsorbent within the short period. The sorption data were then correlated with the freundlich and the langmuir adsorption isotherm models. In both isotherms exhibited a maximum K value in which indicates that the orange peel has greater affinity for methylene blue. The maximum color removal efficiencies of orange peel at dosage of 1.0g for time duration of 45 min found to be 99% of the dye from an aqueous solution of 12.32 ppm. From the study it is understood that pH, contact time and adsorbent dosage plays a vital role in removal of dye. Keywords: Adsorbent, Methylene blue, pH, Orange peel, Neem leaves, Banana peel, 1 Introduction Dyes are chemicals, which on binding with a material will give color to them. Dyes are ionic, aromatic organic compounds with structures including aryl rings, which have delocalized electron systems. The color of dye provided by the presence of a chromophore group. A chromophore is a radical configuration consisting of conjugated double bonds containing delocalized electrons. The Chromogen, which is the aromatic structure normally containing benzene, naphthalene or anthracene rings, is part of a chromogenchromophore structure along with an auxochrome. The presence of ionising groups known as auxochromes results in a much stronger alteration of the maximum absorption of the compound and provides a bonding affinity. Colored dye wastewater arises as a direct result of the production of the dye and because of its use in the textile and other industries. There are more than 100,000 commercially available dyes with over 7 x 10 5 of dyes produced annually worldwide [12]. Dyes are widely used in industries such as textile, rubber, paper, plastic, cosmetic etc. Among these various industries, textile ranks first in usage of dyes for coloration of fiber. The convectional biological treatment process is not very effective in treating a dyes wastewater, due to low biodegradation of dyes. It is usually treated by either physical or chemical
Received on March 2011 Published on April 2011
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Dye removal from aqueous solution using low cost adsorbent
processes. However, these processes were very expensive and could not be effectively used to treat the wide range of dyes waste [Grag et al, 2003]. The adsorption process is one of the effective methods for removal dyes from the waste effluent. The process of adsorption has an edge over the other methods due to its sludge free clean operation and completely removed dyes, even from the diluted solution. Activated carbon (powdered or granular) is the most widely used adsorbents because it has excellent adsorption efficiency for the organic compound. Nevertheless, commercially available activated carbon is very expensive. Furthermore, regeneration using solution produced small additional effluent while regeneration by refractory technique results in a 1015% loss of adsorbents and its uptake capacity [Shaobin Wang et al, 2005]. The sorption data have been correlated with adsorption isotherm to determine the efficiency of adsorption process. Numerous researchers worked earlier on variety of adsorpents as mentioned below. Wool Fiber and Cotton Fiber [Rasheed Khan et al, 2005], Banana pith [Namasivayam et al, 1993a,1993b], Biogas residual slurry [Namasivayam et al, 1992a], Carbonized coir pith [Namasivayam et al, 2001a], Coir pith [Namasivayam et al, 2001b,2002], Chitosan [Juang et al, 1996], Hardwood [Asfour et al, 1985], Mahogany sawdust, rice husk [Namasivayam et al,1992b], Parthenium hysterophorus [Rajeshwarisivaraj et al, 2002], Neem (Azadirachta Indica) husk [Alau et al, 2010], Rice husk [Singh et al, 2001], Rice husk [Guo et al, 2003], Silk cotton hull, coconut tree sawdust [Kadirvelu et al, 2003], Gypsum [Muhammad Rauf et al, 2009], Tuberose Sticks [Ahsan habib et al, 2006], Tamarind Fruit Shell[Papita Saha 2010]. 2 Experimental Investigations 2.1 Preparation of the Adsorbent Adsorbents like Orange Peel, Neem leaves and Banana peel collected from the local areas of Thanjavur District. The peels and leaves collected and dried at low temperature (
