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Dindigul, India

Rajam K.,k-Technology | Rajendran S.,GTN Arts College | Saranya R.,Jayalakshmi Institute of Technology
Journal of Chemistry | Year: 2013

The inhibition efficiency (IE) of an aqueous extract of garlic in controlling corrosion of carbon steel in well water in the absence and presence of Zn 2 + has been evaluated by mass-loss method. The formulation consisting of 2 mL of garlic extract and 25 ppm Zn 2 + offers 70 inhibition efficiency to carbon steel immersed in well water. Polarization study reveals that this formulation controls the anodic reaction predominantly. FTIR spectra reveal that the protective film consists of Fe 2 + -allicin complex and Zn(OH) © 2013 K. Rajam et al. Source


Kousalya G.N.,GTN Arts College | Rajiv Gandhi M.,Gandhigram Rural University | Sairam Sundaram C.,Karaikal Polytechnic College | Meenakshi S.,Gandhigram Rural University
Carbohydrate Polymers | Year: 2010

Biocomposites made up of nano-hydroxyapatite (n-HAp) with chitin and chitosan have been prepared and used for the removal of Fe(III) from aqueous solution. The sorption capacity (SC) of n-HAp, n-HAp/chitin (n-HApC) composite and n-HAp/chitosan (n-HApCs) composite was found to be 4238, 5800 and 6753 mg/kg respectively. Batch adsorption studies were conducted to optimize various equilibrating conditions like contact time, pH and co-ions. The sorbents were characterized by FTIR and EDAX analysis. The sorption process follows Langmuir isotherm. Thermodynamic studies revealed that the sorption of Fe(III) on these composites is spontaneous and endothermic in nature. Both the composites showed higher SC than the n-HAp. © 2010 Elsevier Ltd. All rights reserved. Source


Kousalya G.N.,GTN Arts College | Gandhi M.R.,Gandhigram Rural University | Viswanathan N.,Anna University | Meenakshi S.,Gandhigram Rural University
International Journal of Biological Macromolecules | Year: 2010

Chitin (C), a biopolymer which showed moderate sorption capacity (SC) towards Cu(II) and Fe(III) was suitably modified to enhance the SC. Three types of modifications viz., protonated chitin (PC), carboxylated chitin (CC) and grafted chitin (GC) were carried out to increase the SC. The modified forms of chitin showed enhanced SC for both Cu(II) and Fe(III) than the raw chitin. These sorbents were characterized by the FTIR and SEM with EDAX analysis. The various influencing parameters viz., contact time, pH and the interference of common anions during the sorption have been investigated. The sorption data was reasonably explained using Freundlich and Langmuir isotherms. The calculated values of thermodynamic parameters indicated that, the sorption is spontaneous and endothermic in nature. The order of selectivity of Cu(II) and Fe(III) on modified chitin was found to be Fe(III) > Cu(II). The suitability of modified chitin has been tested with the field samples collected in a near by industrial area. The suitable mechanism for the respective metal removal has been established. © 2010 Elsevier B.V. Source


Rajiv Gandhi M.,Gandhigram Rural University | Kousalya G.N.,GTN Arts College | Viswanathan N.,Anna University | Meenakshi S.,Gandhigram Rural University
Carbohydrate Polymers | Year: 2011

In order to increase the copper sorption capacity (SC) of raw chitosan beads (CB), they were chemically modified into protonated chitosan beads (PCB), carboxylated chitosan beads (CCB) and grafted chitosan beads (GCB) which showed a significant SC of 52, 86 and 126 mg/g respectively while raw chitosan beads (CB) displayed only 40 mg/g. Among the sorbents studied, GCB experienced a higher SC than CB, PCB and CCB. Sorption experiments were performed by varying contact time, pH, presence of co-anions, different initial copper concentrations and temperature for optimization. The nature and morphology of the sorbents were discussed using FTIR and SEM analysis. The copper uptake onto PCB, CCB and GCB obeys the Freundlich isotherm. Thermodynamic studies revealed that the nature of copper sorption is spontaneous and endothermic. © 2010 Elsevier Ltd. All rights reserved. Source


Kousalya G.N.,GTN Arts College | Rajiv Gandhi M.,Gandhigram Rural University | Meenakshi S.,Gandhigram Rural University
Adsorption Science and Technology | Year: 2010

In the present investigation, bio-inorganic composites composed of nano-hydroxyapatite (n-HAp) with chitin and chitosan have been prepared and used for the removal of chromium(VI) ions from aqueous solution. Such composites exhibited a higher Cr(VI) ion sorption capacity than the individual components. The sorption capacities of n-HAp, n-HAp/chitin (n-HApC) composite and n-HAp/chitosan (n-HApCs) composite were found to be 2720, 2845 and 3450 mg/kg, respectively. Batch adsorption studies were conducted to optimize various equilibrating conditions such as the contact time, pH and co-ions. The sorbents were characterized by FT-IR spectroscopy, BET and EDXA analysis. The sorption process could be fitted by both the Freundlich and Langmuir isotherm models. Standard thermodynamic parameters such as the Gibbs' free energy change, ΔG 0, the standard enthalpy change, ΔH 0, and the standard entropy change, ΔS 0, were calculated in order to obtain an understanding of the nature of the sorption process. The kinetics of the reaction could be fitted by the pseudo-second-order and intra-particle diffusion models. The mechanism for Cr(VI) ion sorption onto the composites was established. Source

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