Commonly available herbal leaves powder namely Achyranthes aspera (uthareni) and Phyllanthus niruri (Nela usiri) are used as biosorbents for the removal of malathion in the present investigation. The efficiency of the...Commonly available herbal leaves powder namely Achyranthes aspera (uthareni) and Phyllanthus niruri (Nela usiri) are used as biosorbents for the removal of malathion in the present investigation. The efficiency of the biosorbents is tested for the determination of malathion using batch experiments under controlled conditions as a function of pH, contact time, initial malation concentration and the optimization amount of biosorbents. The quantification of malathion in aqueous samples, before and after equilibration with biosorbents is carried out by existing spectrophotometric method based on the oxidation of malathion with excess N-bromosuccinimide (NBS) and Rhodamine B at (?max = 550 nm) is used for the unconsumed NBS. The biosorption capacities are found to be pH dependent. The maximum adsorption is noticed at pH = 6 with a contact time of 120 minutes. Biosorption equilibrium isotherms are plotted for malathion uptake capacity (Qe) against residual malathion concentration (Ce) in solution. The Qe versus Ce sorption isotherms relationship is expressed mathematically by Langmuir and Freundlich models. The removal of malathion using biosorbents Achyranthes aspera (Uthareni) and Phyllanthus niruri (Nela usiri) from spiked river water samples are found to be 94% and 96% respectively. The developed eco-friendly potential biosorbents indicate that the present method can be successfully applied for the quantitative determination and removal of malathion from real water samples.展开更多
The application of biopolymers such as chitosan is one of the emerging sorption methods for the removal of metal ions, even at low concentrations. A rapid, sensitive and selected method is de- scribed for preconcentra...The application of biopolymers such as chitosan is one of the emerging sorption methods for the removal of metal ions, even at low concentrations. A rapid, sensitive and selected method is de- scribed for preconcentrative determination of vanadium(V) using the synthesized 3-Hydroxyben- zaldehyde-4 Amino antipyrine (HBAP), which was chemically immobilized on chitosan. This is easy to prepare in comparison to many other sorbents. The synthesized sorbent material was se- lective to vanadium(V) within a better response time of 30 min. The method was selective in presence of other foreign ions like Cl-, F-, , , Na+, Ca2+, Zn2+, Fe3+, Fe2+, Cu2+, Cr3+, EDTA, Mn2+, Co2+ and Ni2+. The calibration plots were linear over the concentration range of 0.5 μg·L-1 to 7 μg·L-1 of vanadium(V). These values are 100 times lower than by the direct determination of vanadium by FAAS. The developed procedure was reproducible with a relative standard deviation of 2.84%. The developed sorbent was successfully applied for the determination of vanadium(V) in real water and soil samples. Unlike most preconcentration procedures, the present enrichment method allowed for a rapid and reliable determination of vanadium(V) in environmental samples by the simple and routinely available flame atomic absorption spectrometry technique.展开更多
文摘Commonly available herbal leaves powder namely Achyranthes aspera (uthareni) and Phyllanthus niruri (Nela usiri) are used as biosorbents for the removal of malathion in the present investigation. The efficiency of the biosorbents is tested for the determination of malathion using batch experiments under controlled conditions as a function of pH, contact time, initial malation concentration and the optimization amount of biosorbents. The quantification of malathion in aqueous samples, before and after equilibration with biosorbents is carried out by existing spectrophotometric method based on the oxidation of malathion with excess N-bromosuccinimide (NBS) and Rhodamine B at (?max = 550 nm) is used for the unconsumed NBS. The biosorption capacities are found to be pH dependent. The maximum adsorption is noticed at pH = 6 with a contact time of 120 minutes. Biosorption equilibrium isotherms are plotted for malathion uptake capacity (Qe) against residual malathion concentration (Ce) in solution. The Qe versus Ce sorption isotherms relationship is expressed mathematically by Langmuir and Freundlich models. The removal of malathion using biosorbents Achyranthes aspera (Uthareni) and Phyllanthus niruri (Nela usiri) from spiked river water samples are found to be 94% and 96% respectively. The developed eco-friendly potential biosorbents indicate that the present method can be successfully applied for the quantitative determination and removal of malathion from real water samples.
文摘The application of biopolymers such as chitosan is one of the emerging sorption methods for the removal of metal ions, even at low concentrations. A rapid, sensitive and selected method is de- scribed for preconcentrative determination of vanadium(V) using the synthesized 3-Hydroxyben- zaldehyde-4 Amino antipyrine (HBAP), which was chemically immobilized on chitosan. This is easy to prepare in comparison to many other sorbents. The synthesized sorbent material was se- lective to vanadium(V) within a better response time of 30 min. The method was selective in presence of other foreign ions like Cl-, F-, , , Na+, Ca2+, Zn2+, Fe3+, Fe2+, Cu2+, Cr3+, EDTA, Mn2+, Co2+ and Ni2+. The calibration plots were linear over the concentration range of 0.5 μg·L-1 to 7 μg·L-1 of vanadium(V). These values are 100 times lower than by the direct determination of vanadium by FAAS. The developed procedure was reproducible with a relative standard deviation of 2.84%. The developed sorbent was successfully applied for the determination of vanadium(V) in real water and soil samples. Unlike most preconcentration procedures, the present enrichment method allowed for a rapid and reliable determination of vanadium(V) in environmental samples by the simple and routinely available flame atomic absorption spectrometry technique.
