| Flow injection-spectrophotometry (abbr. FI-S) is a method which combines flow injection analysis and spectrophotometry. When FI-S is introduced into studying the adsorption kinetics of dye on adsorbent, it not only overcomes the shortcoming of conventional colorimetry which is difficult to detect the adsorption process online because of the limit of spectrophotometer, but also has various advantages over colorimetry, such as the precise sample quantity, low sample consume and high automatization level. In this thesis, the experimental techniques of FI-S applied to study batch kinetic adsorption of dye on adsorbent were developed on the basis of He G P et al's work, furthermore, the adsorption behaviors of some dyes on activated carbon, cross-linked chitosan and strongly basic anion exchanger (D290 resin) were studied by FI-S. The adsorption kinetics with respect to the initial dye concentration, adsorbent dosage and temperature were investigated. In addition, the research laid emphases on the effects of ionic strength (NaCl) and methanol percentage in dye solutions on the kinetic characteristics of dyes adsorption on activated carbon and cross-linked chitosan, and the comparison of anionic dyes adsorption behaviors among the Cl-, Br-, I-, NO3- , SO42- form D290 resins. On the other hand, according to the relevant adsorption parameters, the mechanisms of effects of ionic strength, temperature and methanol percentage were discussed in detail in the aspects of adsorption kinetics, thermodynamics and absorbent-dye interaction energy.The experimental results indicated that:1. In various adsorption environment investigated, the adsorption kinetics of cationic and anionic dyes on activated carbon, that of anionic dyes on cross-linked chitosan, and that of Acid chrome blue K (an anionic dye) on D290 resin could be well described by the solid-liquid interface adsorption kinetic equation, whereas that of Alizarin red (an anionic dye) on D290 resin fitted well with the intraparticle diffusion model.2. The apparent rate constants of anionic dyes adsorption on activated carbon, cross-linked chitosan and D290 resin each decreased with the rise of initial dye concentration or adsorbent dosage. The adsorption isotherms of Acid chrome blue K on activated carbon and Cl- form D290 resin agreed well with the Freundlich and Langmuir equations, respectively. The adsorption isotherm of Eosin Y (an anionic dye) on cross-linked chitosan could be well fitted by the Freundlich equation.3. The increase of ionic strength had an acceleration effect on the adsorption kinetics of cationic and anionic dyes on activated carbon, but had a retardation effect on the adsorption of anionic dye on cross-linked chitosan. These two distinct effects were related to the property differences between two kinds of adsorbents. Thermodynamically, the changes in free energy for adsorption of Acid chrome blue K on activated carbon decreased from positive to negative with increasing ionic strength at each temperature investigated, but the changes in enthalpy and entropy of adsorption were positive and both increased with increasing ionic strength. Whereas, at every ionic strength level and temperature investigated, the changes in free energy for adsorption of Acid chrome blue K on cross-linked chitosan were negative and increased with increasing ionic strength, but decreased with the rise of temperature.4. The absorbent-dye interaction energies reflected the effects of various factors (such as the initial dye concentration, temperature and ionic strength) on the adsorption systems at the microcosmic level, moreover, their values could be well correlated to these factors and the relevant adsorption parameters.5. The increase of methanol percentage in dye solutions led to the decrease of adsorption rates of cationic dyes on activated carbon and those of anionic dyes on cross-linked chitosan, but led to the increase of adsorption rates of anionic dyes on activated carbon. Additionally, with increasing methanol percentage, the ad...
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