الفهرس | Only 14 pages are availabe for public view |
Abstract The thesis consists of three chapters, concerned with telluric acid complexes of transition metal ions at higher oxidation states, modification of 6-chloro-6-deoxycellulose derivative with disodium tellurate Part I: Introduction This part is concerned with a literature survey on the chemistry of cellulose, modification of cellulose, especially the direct modification of the primary hydroxyl group, polyoxy-anion ligands, telluric acid and its complexes of transition metal ions at high oxidation states. Moreover, adsorptions of chromium ions and hazard metal ions on solid supports and bio-supports from aqueous media, respectively, have been reported. Part II: Experimental This chapter is concerned with the preparations of tellurato complexes, Na5[M(TeO4(OH)2)2] (M(III) = Cu, Ag, Au), Na5[Cr(TeO4(OH)2)2 (H2O)2], Na6[M’(TeO4(OH)2)2] (M’(II) = Zn, Pd), [TeM”6O24]6- (M”(VI) = Cr, Mo, W). The preparations of modified cellulose derivatives, Cell-Cl, Cell-TeO(OH)4(ONa)/Cell-Cl as well as its Cr(III) complex, [Cr(Cell-TeO3(OH)3/Cell-Cl)(Cell-TeO2(OH)4/Cell-Cl)(H2O)3] were included. The experimental details of the pH-metric measurements of telluric acid and its divalent (Co, Ni, Cu, Zn, and Pd) complexes and that of the modified cellulose derivative, Cell-TeO(OH)4(ONa)/Cell-Cl, and its Cr(III) complex. Adsorption measurements of Cr(III) on the chemically modified cellulose derivatives, Cell-TeO(OH)4(ONa)/Cell-Cl and Cell-TeO(OH)4(ONa)/Cell-Cl-cbgalgae, were discussed. In addition, this part includes the materials, instruments and tools applied in this thesis. Part III: Results and Discussion This chapter is concerned with the preparation and characterization of telluric acid complexes with Cr(III), Cr(VI), Cu(III), Zn(II), Mo(VI), Pd(II), Ag(III), Au(III) and W(VI) as well as the chemically modified cellulose derivatives, Cell-Cl and Cell-TeO(OH)4(ONa)/Cell-Cl, as well as the later Cr(III) complex. The structures of the complexes (in both free and anchored on modified cellulose states) have been discussed on the bases of elemental analysis, spectral (IR, Raman, UV-vis. and solid state 13C-NMR), Morphological (SEM and XRD), magnetic, thermal and pH-metric measurements. Applications: 1- Quantitative separation of Cr(III) from aqueous media onto the modified cellulose derivative, Cell-TeO(OH)4(ONa)/Cell-Cl. The reported support was found to be good sorbent for Cr(III) or Cr(VI) after reduction to Cr(III) with an adsorption capacity of 47.5 mg g-1. 2- The biological modification of the chemically modified cellulose derivative, Cell-TeO(OH)4(ONa)/Cell-Cl, with cyanobacteria green algae (cbgalgae) show high adsorption capacity (93.48 mgg-1) at ratio 3:2 (W:W) of Cell-TeO(OH)4(ONa)/Cell-Cl : cbgalgae, respectively. |