Grafting on high alpha-cellulose pulp extracted from sunflower stalks for removal of Hg [II] from aqueous solution

Dissolving pulp containing 95.5% a-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 [L.R], ceric ammonium nitrate [CAN] concentration as a catalyst, Aam concentration as well as reaction time and temperature. The grafted PSFS [GPSFS] samples were chracterized by estimation of nitrogen%. The optimum conditions for grafting are, PSFS, Ig; L.R, 1:15; CAN, 20mmole/l; Aam, Ig; Temp., 60°C and time 3hr. 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, adsobent concentation, temperature and agitation time. The adsorption data show that, the maximum adsorption capacity, q,, of Hg [II] onto GPSFS is 625mg/g. The adsorption data also showed that the adsorption of Hg [II] onto GPSFS obeys Langmuir and Freundlish isotherms

Adsorption of Cr [VI] oxyanions onto modified wood pulp

A new adsorbent was prepared from wood pulp [WP] after reaction with epichlorohydrin and dimethylamine in the presence of pyridine and N,N-dimethylformamide [DMF]. The adsorption of Cr [VI] from aqueous solutions by the so-prepared wood pulp adsorbent [WP-A] was investigated. Various factors affecting adsorption, such as pH, adsorbent concentration [1-5 g/l], agitation time [5-60min], and Cr [VI] concentration [50-700] were taken into consideration. The adsorption of Cr [VI] onto [WP-A] was found to be pH-dependent and maximum adsorption was obtained at pH 3. The adsorption data obeyed Langmuir and Freundlich adsorption isotheims. The Langmuir adsorption capacity [Qmax] was found to be 588.24 mg/g. Freundlish constants, K[f] and n, were found to be 55.03 and 2.835, respectively.