Adsorption potentialites of bio-sorbents derived from prosopis cineraria and hibiscus rosa-sinensis in the removal of methyl orange dye from polluted waters.

Leaves, stems and their ashes of Prosopis cineraria and Hibiscus rosa-sinensis have been explored for their surface sorption abilities towards Methyl Orange Dye using simulated waters. Various physicochemical parameters such as pH, time of equilibration and sorbent concentrations are optimized for evoking the sorption potentialities of the plant materials for the maximum extraction of the Methyl Orange Dye from waters. The surface sorption nature is found to pH sensitive and % of removal is maximum near pH: 3. % removal of the Dye is more with ashes than respective bio-materials. Co-anions, in fivefold excess, are found to be interfering in the order: trivalent anion>divalent > monovalent while co-cations have shown relatively less interference on the extraction of the Dye at optimum conditions of extraction. The adoptability of the methodologies developed is tested with some real industrial effluents.

New bio-sorbents in the control of chromium (VI) pollution in waste waters.

The sorption abilities of leaves powders of Bhringraj , Aerva lanata, Trianthema portulacastrum L for extracting Chromium (VI) from polluted waters have been studied with respect to various physicochemical parameters such as pH, sorption dosage and equilibrium time. The conditions for maximum removal of Chromium (VI) have been optimized. Ten fold excess of common cation ions present in natural waters, viz., Ca2+, Mg2+ , Cu2+, Zn2+, Ni2+ and Fe2+ have synergistic effect in increasing the % removal of Chromate. SO4 2—and Phosphates are found to be interfering with the extractability of Chromates but NO3 - , Chloride, Fluoride and Carbonate have marginal interference. However, the extraction has never come down below 72.0%. Maximum extractions to an extent of 96.0%, 92.0%, and 84.0% from synthetic waters are observed with the leaves powders of Bhringraj , Aerva lanata, Trianthema portulacastrum L respectively at pH:2 and at optimum equilibration time and sorbent concentrations. The methodologies developed are applied to diverse waste water samples collected from industrial effluents and polluted lakes. The procedures are found to be remarkably successful in removing the Chromiume(VI) from waste waters.

Removal of phosphates from polluted waters using bio-adsosrbents.

Increasing interest is being envisaged by environmental researchers in controlling the phosphates pollution in natural waters by evoking the surface sorption characteristics of bio-waste materials of flora origin. In the present work, a thorough investigation has been made to find powders of leaves or their ashes of different classes of plants, having the affinity towards phosphate ions. 10 plant leaves and their ashes have been found to have sensitivity towards Phosphate ion. Investigations have been made in optimizing the various physico-chemical parameters such as equilibration time, pH and sorption dosage for the maximum removal of phosphates. The % of removal is found to be increasing with the increase in pH and equilibration time. The ashes of leaves shows more sorption towards phosphates than powders of leaves.79% to 90% removal of phosphate from polluted waters are found at optimum conditions with the sorbents investigated in this work. The interference of foreign ions on the % of extraction of phosphate reveals that some divalent cations are found be synergizing the extraction and thereby % of removal of Phosphate is increased even in the presence of 500 ppm of the said ions.