Grafting of high α-cellulose pulp extracted from sunflower stalks for removal of Hg (II) from aqueous solution

Dissolving pulp containing 95.5% alpha-cellulose was extracted from sunflower stalks. The pulped sunflower stalks ( PSFS) were used as starting material for grafting with acrylamide (Aam). All factors affecting the grafting reaction were examined. These factors include liquor ratio (LR), ceric ammonium nitrate ( CAN) concentration as a catalyst, Aam concentration, as well as reaction time and temperature. The grafted PSFS (GPSFS) samples were characterized by estimation of nitrogen %. The GPSFS was utilized as adsorbent material to remove Hg(II) ions from aqueous solutions. All factors affecting adsorption process were examined. These factors include pH, adsorbent concentration, temperature, and agitation time. The adsorption data show that the maximum adsorption capacity, q(e), of Hg (II) onto GPSFS is 625 mg/g. The adsorption data also showed that the adsorption of Hg (II) onto GPSFS obeys Langmuir and Freundlich isotherms.