In this study, novel adsorbents were prepared, characterized and investigated for adsorption of gadolinium as
one of rare earth elements. The first adsorbent is rice husk ash (RHA), the second is poly(acrylamide/acrylic
acid/sodium styrene sulfonate) resin (P), the third and fourth adsorbents were the prepared resin grafted on
the surface of the silica powder (poly(acrylamide/acrylic acid/sodium styrene sulfonate/silica powder) (P-SP)
and gel form (poly(acrylamide/acrylic acid/sodium styrene sulfonate/silica in gel form) (P-SG) extracted from
the first adsorbent (RHA) using alkaline treatment. These grafted resins as novel adsorbents were prepared by
60Co gamma-rays irradiation of 25 kGy. Characterization of the new prepared adsorbents were investigated;
swelling kinetics, ash content, FTIR, TGA & DTA, BET surface area and their ability for adsorption of some organic
compound (Methylene Blue and P-Nitro-phenol from aqueous solution. It was found that: the swelling ratios
take the following order: 28.55, 24.08 and 20.46% for P-SG, P and P-SP, respectively. The P-SP has the highest
value of ash content 9.5%, and the BET surface areaswere 8.5, 4.3 and 2.815m2/g for P-SG, P-SP and P, respectively.
For the adsorption of MB, the maximumcapacity (qm) was 277, 171.5 and 174.2 (mg/g), but for adsorption of
P-NP it was 51.1, 38.6 and 52.99 (mg/g) for P, P-SP and P-SG. Finally, the new prepared four adsorbents were investigated
for adsorption of Gd(III). The results showed high adsorption capacity; 229.36, 206.61, 184.84 and
133.33 for P-SG, P-SP, P and RHA, respectively. From this study we can conclude that the prepared four adsorbents
can be used for sorption of Gd(III) as well as some organic compounds from aqueous solution. |
