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Kayalvizhi K.,TamilNadu Pollution Control Board | Vijayaraghavan K.,Indian Institute of Technology Madras | Velan M.,Anna University
Desalination and Water Treatment | Year: 2014

Heavy metal pollution is a major environmental concern in many countries. Among heavy metals, chromium is one of the widely used despite being one of the most toxic metal ions. The present study deals with the evaluation of Cr(VI) biosorption using a novel fresh water alga Rhizoclonium hookeri. Batch experiments were conducted and the maximum adsorption capacity was evaluated as 67.3 mg/g at pH 2 at a biomass dosage of 1 g/L and 1,000 mg/L initial Cr(VI) concentration. Fourier transform infrared spectroscopy analysis of alga before and after biosorption revealed a shift in the carboxylic O-H stretching vibration from 3,401 to 3,373 cm-1, which confirmed its involvement in biosorption of Cr(VI) by R. hookeri. Surface morphology of alga was examined using the scanning electron microscopy, which indicated the highly porous nature of biomass. Non-linear regression analyses of isotherm models revealed that the three-parameter model isotherms (Redlich-Peterson and Sips) better described the experimental data compared with two-parameter model isotherms (Langmuir and Freundlich). An analysis of the kinetic models (pseudo-first-order, pseudo-second-order and Elovich models) indicated that the experimental data followed pseudo-second-order kinetics. The thermodynamic parameters such as free energy, enthalpy and entropy were calculated and Cr(VI) biosorption was found to be a spontaneous and endothermic process. © 2014 © 2014 Balaban Desalination Publications. All rights reserved.

Prakash Maran J.,Kongu Engineering College | Sivakumar V.,Kongu Engineering College | Thirugnanasambandham K.,Kongu Engineering College | Sridhar R.,TamilNadu Pollution Control Board
Carbohydrate Polymers | Year: 2013

In this study, microwave-assisted extraction was applied for pectin extraction from the dried orange peel and Box-Behnken response surface design was used to study and optimize the effects of processing variables (microwave power, irradiation time, pH and solid-liquid ratio) on the yield of pectin. The amount of pectin extracted increased with increasing microwave power, while it reduces as the time, pH and solid-liquid ratio increased. From the results, second order polynomial model was developed and it adequately explained the data variation and significantly represented the actual relationship between independent variables and the response. An optimization study using Derringer's desired function methodology was performed and optimal conditions based on both individual and combinations of all independent variables (microwave power of 422 W, irradiation time of 169 s, pH of 1.4 and solid-liquid ratio of 1:16.9 g/ml) were determined with maximum pectin yield of 19.24%, which was confirmed through validation experiments. © 2013 Elsevier Ltd. All rights reserved.

Prakash Maran J.,Kongu Engineering College | Sivakumar V.,Kongu Engineering College | Thirugnanasambandham K.,Kongu Engineering College | Sridhar R.,TamilNadu Pollution Control Board
International Journal of Biological Macromolecules | Year: 2013

In this work, four factors with three level Box-Behnken response surface design was employed to investigate the influence of process variables (maize starch, sorbitol, agar and Tween-80) on the barrier (water vapor permeability, oxygen permeability, thickness, moisture content and solubility) and optical (transparency) properties of the maize starch based edible films. Casting method was employed to prepare the edible films. The results showed that, addition of sorbitol and Tween-80 reduces the water vapor and oxygen permeability of the films, its due to the reduction of molecular mobility between polymer matrixes, where as, it also increases the thickness, moisture content, solubility and transparency of the films. The results were analyzed using Pareto analysis of variance (ANOVA) and second-order polynomial models are developed for all responses in order to predict the effect of process variables over the barrier and optical properties of the films. © 2013 Elsevier B.V.

Suganya S.,SSN College of Engineering | Kayalvizhi K.,TamilNadu Pollution Control Board | Senthil Kumar P.,SSN College of Engineering | Saravanan A.,SSN College of Engineering | Vinoth Kumar V.,SRM University
Desalination and Water Treatment | Year: 2016

The adsorption of Pb(II), Ni(II), and Cr(VI) ions onto Rhizoclonium tortuosum (RT) was investigated in a batch mode operation. The two parameter (Langmuir and Freundlich) and three parameter models (Redlich–Peterson and Sips isotherm model) were used to depict the adsorption of metal ions onto R. tortuosum. Sips isotherm model was provided the best fit to the adsorption equilibrium data. The adsorption kinetics was described by the pseudo-first-order, pseudo-second-order, and Elovich kinetic models. The pseudo-second-order model provides the best fit. The maximum monolayer adsorption capacity of the RT were found to be 66.08, 85.09, and 61.45 mg/g for Pb(II), Ni(II), and Cr(VI), respectively. The thermodynamic results showed that the adsorption process was endothermic, feasible, and spontaneous in nature. The ability of RT to remove the Ni(II) ions in column studies was explored. The effect of bed height, flow rate, and initial Ni(II) ion concentration were studied. The dynamic behavior of the column performance was studied using the bed depth service time (BDST) and Thomas models. This research was also further extended to treat the nickel contaminated plating industrial wastewater. The results showed that the RT can be utilized as better biosorbent for the removal of metal ions from industrial wastewater. © 2016 Balaban Desalination Publications. All rights reserved.

Gomathy G.,Tamil University | Gomathy G.,Valliammal College for Women | Vijay T.,SMK Fomra Institute of Technology | Sarumathy K.,TamilNadu Pollution Control Board | And 2 more authors.
Journal of Applied Pharmaceutical Science | Year: 2012

The investigation was carried out to determine the qualitative analysis of phytochemical screening and possible chemical components of Mukia maderaspatana (L.) (family: Cucurbitaceae), leaves GC-MS. The plant is an indigenous plant; traditionally it is used as an ingredient of various cocktail preparations and for the management of severe inflammatory disorders in Indian system of medicine. GC-MS analysis of hydroalcoholic extract lead to identification of 7 compounds. This analysis revealed that contains Mukia maderaspatana (L.) leaves mainly Dichloroacetic acid, 4-methylpentyl ester, 2-Butyn-1-ol, 4-methoxy and also showed the presence of other constituents like flavonoids, saponins, carbohydrates, steroids, tannins and phenolic compounds.

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