NOPR Collection:

Spectrophotometric determination of iron(III) in ore, pharmaceutical formulations, plant material and foodstuff using piroxicam

Sat, 01 Mar 2003 00:00:00 GMT

Title: Spectrophotometric determination of iron(III) in ore, pharmaceutical formulations, plant material and foodstuff using piroxicam Authors: Melwanki, M B; Seetharamappa, J; Masli, S P Abstract: Piroxicam (PR) has been proposed as a sensitive and selective reagent for the spectrophotometric determination of Fe(III) in ore, pharmaceutical formulations, plant material and foodstuff. The method is based on the formation of a chloroform-soluble red coloured 1:1 complex by the reaction of Fe(III) with PR in Walpole buffer. Beer's law is valid over the concentration range of 0.4-6.4 ppm. The coloured complex exhibits an absorption maximum at 510 nm with molar absorptivity of 1.82×10⁴ l mol^-1 cm^-1 and Sandell's sensitivity of 17.32 ng cm^-2. The absorbances are found to increase linearly with increase in concentration of iron, which are corroborated by the calculated correlation coefficient value (0.9992). The effects of foreign ions in the determination of Fe(III) have been studied. Statistical comparison of the results with those of direct AAS method shows good agreement and indicates no significant difference in precision. Page(s): 576-578

Faujasitic zeolite as sorbent for copper removal

Sat, 01 Mar 2003 00:00:00 GMT

Title: Faujasitic zeolite as sorbent for copper removal Authors: Rayalu, S S; Agrawal, A; Bawase, M A; Ugwuanyi, J U Abstract: Detailed studies have been conducted for removal of copper ions from its aqueous solution by flyash based faujasitic zeolites. Studies conducted on FAZ-Y and Cu systems reveal that low adsorbate concentration, neutral pH and higher temperatures favour the sorption of Cu ions. Almost 100% removal of the Cu ions has been achieved at a dose of 7 g/l for 500 mgl^-1 for a contact time of 4 h at neutral pH using FAZ-Y. The equilibrium data fits well in the Freund lich and Langmuir adsorption model. Effect of temperature is explained on the basis of the solubility and chemical potential of the adsorbate. The rate of sorption is observed to increase with increase in temperature. Page(s): 573-575

Fluorimetric method for the determination of trace amounts of mercury using 2-hydroxy-l- naphthaldehydene-hydrazinecarbothioamide

Sat, 01 Mar 2003 00:00:00 GMT

Title: Fluorimetric method for the determination of trace amounts of mercury using 2-hydroxy-l- naphthaldehydene-hydrazinecarbothioamide Authors: Jiang, Chongqiu; He, Fang Abstract: A fluorescent reagent, 2-hydroxy-l-naphthaldehydene-hydrazinecarbothioamide (HNHTA) has been synthesized and the fluorescent quenching reaction of this reagent with mercury is studied. Based on this chelation, a highly sensitive spectrofluorimetric method has been developed for the determination of trace amounts of mercury. The interference of other mental ions has also been studied. This method has been successfully applied to the determination of mercury in waste water and prawn. Page(s): 568-572

Spectrophotometric determination of nickel in alloys using 5-mercapto-3-methyl- 4-[2-pyridylideneamino]-1,2,4-triazole (MMPT)

Sat, 01 Mar 2003 00:00:00 GMT

Title: Spectrophotometric determination of nickel in alloys using 5-mercapto-3-methyl- 4-[2-pyridylideneamino]-1,2,4-triazole (MMPT) Authors: Nazareth, Ronald A; Narayana, B Abstract: A simple and rapid spectrophotometric method for the determination of nickel has been developed using 5-mercapto-3-methyl-4-[2-pyridylideneamino]-1 ,2,4-triazole (MMPT). The green coloured 1:2 complex formed shows the absorption maximum at 400 nm. The method is free from interference from many of the associated metal ions. It obeys the Beer's law in the range of 3 ppm to 11.5 ppm of Ni(II) with molar absorptivity and sandell sensitivity of 8.51 × 10³ dm³/mol/cm^-1 and 0.03 μg/cm² respectively. Analyses of various alloys have been carried out with satisfactory and reproducible results. Page(s): 564-567