Browsing by Author "Shyamala Devi, N"

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    CONFISCATION OF NITRATE ION FROM AQUEOUS MEDIUM USING A NOXIOUS AQUATIC WEED - A BOON FROM BANE
    (Indian Journal of Environmental Protection, 2018-06) Shyamala Devi, N; Revathi, R
    Water is an essential natural resource for sustaining life and environment. It is a nature's free gift, but clean and safe drinking water becomes scarce due to rapid industrialization and urbanization. The elevated levels of nitrate (N03∼) in drinking water leads to severe impacts on the environment. Water hyacinth (WH) an aquatic weed grow at a faster rate in polluted waters containing dissolved nitrogen and phosphorous. The present study focused on the removal of nitrate anions from aqueous solution through adsorption technique. The chosen biomaterial is chemically modified using phosphoric acid to enhance its sorption efficiency, thereafter referred as modified water hyacinth (MWH). To characterize the surface functional group and morphology of the adsorbent scanning electron microscopy and FT-IR analyses are recorded. The competence of the sorbent material is experimentally verified through various operating factors likely particle size, adsorbent dosage, agitation time, initial concentrations of nitrate ions, pH of the medium, an effect of co-ions and influence of temperatures on nitrate-modified water hyacinth system through batch mode. The residual concentrations of nitrate ions from aqueous solutions are analysed using the UV-visible spectrophotometer. Langmuir and Freundlich's models are applied to describe the adsorption capacity. Isotherm plots reveal the mono linearity of both the isotherms onto nitrate-modified water hyacinth system.
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    VIRTUAL SCREENING OF TREATED PISTACHIO VERA SHELL POWDER AS A POTENTIAL SORBENT IN SEQUESTERING UBIQUITOUS DIVALENT METAL IONS FROM AQUEOUS MATRICES
    (Oriental Journal of Chemistry, 2018) Shyamala Devi, N; Muthulakshmi Andal, N; Vivithabharathi, K
    Water pollution due to noxious heavy metals such as Hg(II), Cr(VI), Cd(II) and Pb(II) ions etc., has been tremendously focused gaining attention towards social benefit. Increasing concentrations of these metals into the ecosystem constitute a severe health hazard due to their toxicity, accumulation and bio-magnification throughout the food chain. Lead contamination of drinking water is a great threat through varied sources viz., lead pipes, plating units etc. Pistachio vera shell (PVS) is a hard layer that surrounds the delicious kernel of the nut. The current work evaluates the feasibility of powdered Pistachio vera shell (PVSP) - a biowaste for sequestering Pb (II) ions is treated with 0.1N HCl and 0.1N NaOH to enhance its sorption efficacy (TPVSP). SEM, FTIR and microscopic analyses are recorded for characterising the chosen sorbent. Batch experimental studies are performed to assess the equilibration between the sorbate and the sorbent. The competence of the sorbent material is experimentally verified through various operating factors viz., particle size and dosage of TPVSP, agitation time interval between TPVSP and Pb(II) ions, initial concentrations of Pb(II) ions, pH of the adsorption medium, effects of cations, anions, co-ions and influence of temperatures on Pb(II) – TPVSP system. The residual concentrations of Pb (II) ions from aqueous solutions are analysed using Atomic Absorption Spectrophotometer (Shimadzu-AA-6200). Langmuir and Freundlich models are applied to describe the adsorption capacity. Column studies are conducted to ensure the quantitative estimation of TPVSP in trapping 99% of sorbate species at a dose of 40 mg the flow rate being, 100 ml/10 min. assuring the bulkiness of the materia