International Journal of Science and Research (IJSR) ISSN (Online): 2319-7064 Index Copernicus Value (2013): 6.14 | Impact Factor (2013): 4.438 Volume 4 Issue 2, February 2015 www.ijsr.net Licensed Under Creative Commons Attribution CC BY Evaluation of Adsorptive Capacity of Bioadsorbent in Removal of Congo Red from Aqueous Solution Ekta M. Meshram 1 , Sanjogta M. Meshram 2 1 Assistant Professor, Department of Applied Chemistry, G. N. I.E. T., Nagpur, India. 2 Assistant Professor, Department of Applied Chemistry, R.C.O.E.M, Nagpur, India Abstract: Adsorption techniques are widely used to remove certain classes of pollutants from waters, especially those which are not easily biodegradable. Currently a combination of biological treatment and adsorption on activated carbon is becoming common for removal of dyes from waste water. There are plenty of evidences for removal of pollutants using granular activated carbon as an adsorbent contrary to the fact that even bioadsorbent could serve the purpose, as such alternative non-conventional eco friendly sorbents have been investigated. It is well known that natural materials, waste materials from industry and agriculture waste can be obtained and employed as inexpensive sorbents. In present study an extensive list of sorbent literature has been complied which presents a critical analysis of these materials describes their characteristics, advantages and limitations. In particular, nilgiri bark might be promising adsorbent for environment and its purification purpose. Keywords: Adsorption, Congo red dyes, Wastewater, Nilgiri bark, Neem bark 1. Introduction Synthetic dyes are extensively used in textile dyeing, paper printing, color photography, pharmaceutical, food, cosmetics and other industries [1]. One of the major problem concerning textile wastewater is colored effluent. The discharged of color waste is not only damaging the aesthetic nature of receiving streams but also it may be toxic to aquatic life. The release of colored wastewater from these industries may present an eco-toxic hazard and introduce the potential danger of bioaccumulation, which may eventually affect man through the food chain [2]. Many techniques have been used to remove harmful dyes from colored wastewater: Such as combination of biological, physical and chemical methods including coagulation / flocculation [3], electrochemical oxidation [4], reverse osmosis [5], ozone [6] and oxidative/reductive chemical processes [7]. Currently sorption process is prove to be one of the effective and attractive process for the treatment of these dye-bearing wastewater [8-10]. Activated carbon is the most popular adsorbent for sorption process, which is capable of adsorbing many dyes with a high adsorption capacity [11]. Granular Activated Carbon is widely used for the removal of impurities from water solution [12-15], but it is expensive and the costs of regeneration are high because desorption of the dye molecules is not easily achieved [16- 17]. Congo red is a highly water soluble diazo dye. It is a derivative of benzidine and napthoic acid. It exists as a brownish red crystal. It is an anionic acid dye used as a laboratory aid in testing for free hydrochloric acid in gastric contents, in the diagnosis of amyloidosis, as an indicator of pH and also as a histological stain for amyloid. It metabolizes to carcinogenic products [18]. It has a strong affinity to cellulose fibers and thus is employed in textile industries. It is investigated as a mutagen and reproductive effectors. It is a skin, eye and gastrointestinal irritant. It may affect blood factors such as clotting and induce, somnolence and respiratory problems. The Nilgiri tree (Nilgirianthus heyneanus) of family Acanthaceae are neem tree (Azadirachta indica) of family Meliaceae native to the Indian sub-continent, and its seeds and leaves have been in use since ancient time to treat a number of human ailments and also as a household pesticide. The neem tree itself is known as an air purifier and a variety of medicinal and germicidal properties have been attributed to leaves, bark, seeds and other parts of the plant [19-23]. 2. Experimental Dye solution preparation:- The dye, Congo red is the sodium salt of 3,3’-([1,1’- biphenyl]-4,4’-diyl) bis (4-aminonaphthalene-1-sulfonic acid) (formula : C 32 H 22 N 6 Na 2 O 6 S 2 ; molecular weight : 696.66 g/mol) [24]. Stock solution of Congo Red dye (S.D. Fine Chemical, India, A. R. Grade ) was prepared by dissolving the required amount of dye in distilled water. Experimental solutions of the desired concentrations of Congo red dye were obtained by successive dilutions. Paper ID: SUB151742 2217