Synthesis Of The Complex Of Natural Macromolecule Chitosan And Its Derivatives With Ferrous And Their Application

Chitosan is a nontoxic natural alkali polysaccharide with excellent biocompatibility and medical function that abstracted from the shell of the crust outline animal such as shrimp or crab etc. It can easily form polymer metal complexes with many transitional metal cations and rare-earth metal ions for its extra electron pair of nitrogen. The metal complexes with chitosan or chitosan derivatives exhibit many splendid function in material application. As a good kind of complex material, it possesses a wonderful application foreground at many domains such as pharmaceutical carriers, fixing agent of enzyme, separative membrane.. man-made urea adsorbent , growth induced agent of nano microcrystal, chemistry catalyzes plant growth adjusted agent as well as metal separation and determination the content of metal etc.This thesis has studied the synthesis of the ferrous complexes of chitosan and its derivatives, for example chitosan-ferrous complex , chitosan-8-oxine-ferrous complex , different molecular weight chitosan-ferrous complex, chitosan-ferrous-N-salicylicdene glycine sciff base complex etc. The structure of the coordinating compounds were confirmed by IR spectra, UV-VIS spectra, element analysis and thermal analysis. Their sorption kinetics and thermal decomposition kinetics have been investigated and conjectured their structure. Their elementary application was studied too. The thesis is divided into seven parts: Part â…  : Review.A review of the coordinate chemistry of natural macromolecule chitosan and its derivatives with transitional metal and their application is given.Part â…¡: Study of the adsorption kinetics and mechanism of ferrous ions on chitosanThe sorption isotherm and sorption kinetics of chitosan for ferrous ion have been investigated. Under the optimum sorption conditions of chitosan for ferrous ions, thecoordinating compound between chitosan and ferrous ion was obtained. The structure of the coordinating compound was confirmed by IR specie UV-VIS spectra , element analysis and thermal analysis. The results were satisfied with the Langmuir-single-molecule-layer adsorption mechanism and the Lagergren-one-order equation. The apparent adsorption activation energy is 20.23kJ/mol and the sorption rate constant of the Lagergren-one-order sorption is 0.25h-1 at 293.15K.Part â…¢: Thermal decomposition mechanism and non-isothermal kinetics of the complex of ferrous ion with chitosanThe chelating effect of ferrous ion on chitosan have been investigated. By optimizing with the condition to the adsorption of ferrous ion, we have got the comparatively ideal synthetic product outcome. By way of IR spectrum and UV-VIS spectrum corroborated the chelating effect between chitosan and ferrous ion, and using the element analysis and thermal analysis established the component of the chitosan-ferrous complex. The thermal decomposition of the complex and its kinetics were studied by non-isothermal thermogravimety. The stages of the decomposition were identified by TG-DSC curve. The most probable mechanism function and the kinetic parameters(the activation energy,E and pre-exponential constant,A) were obtained from comparing the kinetic parameters by differential and integral methods.Part â…£: Synthesis of complexes of different molecular weight chitosan-Fe( â…¡) and their sorption capability of ureaThe optimum preparation craft of the different low-molecular weight chitosan were prepared by H2O2-HAC control oxidation method. It was synthesized three kind of chitosan with different low molecular weight(Mv is 870 thousand , 110 thousand and 10 thousand) and had obtained a series of their ferrous complexes by optimizing the coordinate conditions between low-molecular chitosan and ferrous. The optimal adsorption conditions of urea with different molecular weight chitosan-Fe(â…¡) complexes were studied. It was resulted that the complexes exhibit high sorptive capacity and good selectivity for urea. The sorption capacity was influenced by the metal content in the complex, time of sorpti...