الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
In this work, native cellulose cotton fibers were first modified through graft copolymerization of poly acrylonitrile (PAN) and then by insertion of phenyl thiosemicarbazide moieties to finally produce C-PTS chelating fibers, which were fully characterized using various instrumental techniques such as SEM, FTIR, EDX and XRD spectra. The obtained C-PTS were employed in removal and extraction of Au3+, Pd2+and Ag+ precious metal ions from their aqueous solutions using batch experiments. The kinetic studies showed that the pseudo-second-order model exhibited the best fit for the experimental data. In addition, the adsorption isotherm studies indicated that the adsorption follows the Langmuir model and the maximum adsorption capacities for Au3+, Pd2+and Ag+ were 198.31, 87.43 and 71.14 mg/g respectively. And novel selective Au3+ chelating surface ion imprinted fibers based on phenyl thiosemicarbazide modified natural cotton (Au-C-PTS) has been synthesized, and applied for selective removal of Au3+ from aqueous solutions. Batch adsorption experiments were performed with various parameters, such as contact time, pH, initial Au3+ concentration, and temperature. The kinetic studies revealed that the adsorption process could be described by pseudo-second-order kinetic model, while the adsorption data correlated well with the Langmuir and Freundlich models. The maximum adsorption capacities calculated from the Langmuir equation are 140 mg /g and 72 ±1 mg /g at pH 5 for both Au-C-PTS and NI-C-PTS, respectively. The estimated thermodynamic parameters (Gibbs free energy (ΔG), enthalpy (ΔH), and entropy change (ΔS)) indicated the spontaneity and exothermic nature of the adsorption process. Furthermore, the selectivity study revealed that the ion imprinted fibers was highly selective to Au3+ compared with Cu2+, Cd2+, Hg2+, and Fe3+. The adsorbent was successfully regenerated with a 0.1M HNO3 solution. And cellulose fibers were adapted by graft copolymerization of polyacrylonitril (PAN) and then by ingestion of amidoxime moiety to finally generate C-AXO chelating fibers, which were characterized by various instrumental techniques such as SEM, FTIR, EDX and XRD spectra. Using batch tests, the obtained C-AXO was used for removal and extraction of UO22+ and VO2 + from their aqueous solution. The kinetic studies have shown that the pseudo-second - order model is the best fit for the experimental data.