FIXATION OF CR(III) TRACES ONTO HARO RIVER SAND FROM ACIDIC SOLUTION

The sorption of chromium(III) onto Hare river sand has been investigat ed as a function of sorptive solution composition, amounts of sorbent (10-500 mg) and sorbate (4.3310(-8)-5.1710(-6) M), shaking time (I-60 minutes) and temperature (15-35 degrees C). Maximum sorption has been achieved from 0.001M HCI solution using 50 mg of the sand and 20 minut es shaking time. The sorption data followed Freundlich and D-R isother ms. The sorption capacity of 0.4 mu mole . g(-1) and of sorption energ y of 9.9 kJ . mole(-1) have been computed from D-R parameters. Thermod ynamic parameters Delta H = 84.4 kJ . mole(-1), Delta S = 284.5 J . mo le(-1) K-1 and Delta G = -3.32 kJ . mole-1 at 298 K have been evaluate d. Fe(II), Al(III), citrate, berate, oxalate, tartrate and carbonate i ons reduce the sorption significantly. Under similar experimental cond itions Tc(VII), Re(VII), Sb(V) and Co(II) have very low sorption (<1%) and trivalent Eu and Sm have large distribution ratios. Haro river sa nd can be used to preconcentrate or to remove micro or submicro amount s of Cr(III) from very dilute solution and for the separation of Tc, R e and Sb from Cr, Eu and Sm.