Mixed Adsorption Process Of Data Analysis Methods

In this thesis, a multiple linear regression method was employed to analyze the spectrophotometric data in color removal processes. The residual color profiles, the color removal efficiencies, as well as the thermodynamic and kinetic data of single dyes in the mixture of dyes were obtained.1. Data analysis in the adsorption processes of dye from mixture by chitosanThe performances of the chitosan as an adsorbent to remove dyes, namely, Reactive violet K-3R (K-3R), Direct fast scarlet 4BS (DFS-4BS), Eosin Y and Acid scarlet GR (AS-GR) from their mixture have been investigated. By employing a multiple linear regression method, the color removal efficiency and adsorption isotherms of each dye in the mixtures were determined. The experimental results show that the adsorption isotherms of the four dyes onto chitosan from single dye solutions follow Langmuir equation. Based on the modified Langmuir equations for adsorption of mixed dyes, the adsorption equilibrium constants of each dye in the mixture were estimated, which were usually greater than those in single dye solution. The dye with larger adsorption equilibrium constant is preferentially adsorbed on the chitosan.2. Determination of binding equilibrium constants and binding rate constants between poly (epicholorohydrin-diamine) and reactive dyes in their mixtureThe binding processes of Reactive Red K-2BP (K-2BP) and Reactive Violet K-3R (K-3R) onto poly (epicholorohydrin-diamine)(EPI-DMA) in solution and film were investigated by a spectrophotometric and quartz crystal microbalance (QCM) methods, respectively. By using a multiple linear regression technique, the concentrations of the colored components in the mixtures of dye + EPI-DMA were measured simultaneously from the absorbance spectra. The binding equilibrium constants for K-3R and K-2BP onto EPI-DMA in solution were estimated to be 9.31×10⁶ and 1.86×10⁶ L.mol^-1, respectively. The difference in the color removal between K-3R and K-2BP by EPI-DMA was discussed. The binding processes of K-3R and K-2BP onto PEPIDA film were followed by the QCM. The binding equilibrium constants were evaluated to be 1.27×10⁶ and 3.28×10⁵ L.mol^-1 for K-3R and K-2BP onto EPI-DMA film, respectively. They are less than those determined in EPI-DMA solutions. The binding rate constants for K-3R and K-2BP onto EPI-DMA film were estimated to be 1.43×10⁵ and 1.72×10⁵ L.mol^-1.s^-1, respectively.3. Processes analysis for the adsorption of dyes onto polyelectrolyte modified bentonite from multicomponent dye solutionsThe effectiveness of polyelectrolyte modified bentonite in removing dyes from simulated wastewaters was evaluated. Cationic polyelectrolyte, polydiallydimethyl- ammonium chloride (PDMDAAC), was used to modify the surface of bentonite. The performances of PDMDAAC /bentonite as an adsorbent to remove dyes, namely, Acid Scarlet GR, Reactive Violet K-3R, Acid Turquoise Blue 2G and Indigo Carmine, from single dye solutions and the multicomponent dye solutions were investigated. The experimental results show that prepared PDMDAAC/bentonite is an excellent adsorbent for anionic dyes. With sorption from multicomponent dye solutions, the residual color profile and amounts of adsorption of each dye were determined according to a multiple linear regression method. The adsorption isotherm of a dye onto PDMDAAC/bentonite from single dye solutions was fitted well by Langmuir equations. In the region of insufficient dosage of PDMDAAC/bentonite, the dye with a larger adsorption constant or capacity had a lower residual color. The influence of light scattering by the particles in supernatant solution on the color removal efficiency was discussed. And the influence of pH, dosage of PDMDAAC/ bentonite and the time of adsorption were also discussed.4. Data Analysis in color removal processes by cloud point extractionCloud point extraction (CPE) is a new environmentally kind liquid-liquid extraction method. An attempt was made to remove color from simulated wastewater containing dye Acid turquoise Blue A,Direct Turquoise Blue 5B and Reactive Blue K-GL by cloud point extraction using a nonionic surfactant of Triton X-114.When the temperature was above the cloud point, these dyes were extracted into TX-114 nonionic surfactant phase and separated from bulk water. The effects of the concentration of dye, surfactant, temperature, and salt concentration were studied. The color removal from mixture of dyes was also investigated. The extraction efficiency and residual color profiles were determined.