Applications of electron spin resonance in the analytical chemistry of transition metal ions

Fixed-bed column study for hexavalent chromium removal and recovery by short-chain polyaniline synthesized on jute fiber

“…At influent pH of 3, reduction of Cr(VI) to Cr(III) was much less as compared to influent pH 2 ( Fig. 3(d)], confirming the presence of Cr(III) whose standard signal g value is 1.98 [42]. However, chromium bounded PANI-jute after adsorption experiment showed no peak of Cr(III).…”

Removal and recovery of chromium from wastewater using short chain polyaniline synthesized on jute fiber

“…The resonance signal of the effluent solution after adsorption experiment at pH 2 appears at a magnetic field position corresponding to g value of 1.975 [ Fig. 5(b)], confirming the presence of Cr(III) whose standard signal g value is 1.98 [21]. When ESR was employed on effluent solution after adsorption experiment at pH 3 and 4, no spectra was observed indicating insignificant amount of Cr(III) in solution after adsorption experiment at pH 3 and 4.…”

Modeling and evaluation on removal of hexavalent chromium from aqueous systems using fixed bed column

“…4) indicating the presence of Cr(III) in the column (For interpretation of the references to color in this sentence, the reader is referred to the web version of the article.). The presence of Cr(III) in the loaded sorbent was further confirmed by the epr spectra with g value of 1.99 [36]. To evaluate the nature of the species in the effluent, speciation studies were done on the effluent water.…”