Kinetic and Isotherm Modeling of Liquid-Phase Adsorption of Natural Organic Matter, Dye and Metal Ions on LipoSanTM

• Main Authors: Pei-Hsuan Lu, 呂佩璇
• Other Authors: Feng-Chin Wu
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/69232359287878496549

碩士 === 國立聯合大學 === 化學工程學系碩士班 === 101 === Efficient chitosan (LipoSanTM, LS) and traditional chitosan (CS) were used to adsorb environmental pollutants such as: natural organic matter (NOM), dye, and Cu(II) to evaluate the feasibility of LS in adsorption application. Physical and chemical properties of prepared LS and CS were determined by X-ray diffractometer (XRD), Zeta-potential, elemental analysis (EA), thermogravimetric analysis (TGA), and infrared spectroscopy (FT-IR). The adsorption isotherm of equilibrium and kinetics of LS and CS upon the adsorption of NOM (HA, FA, TA, GA), dyes (RB19, RO16, RB5, AO7, AG27), and Cu(II) in aqueous solution were investigated. The equilibrium adsorption data were analyzed by using the Langmuir and Freundlich models. The Langmuir equation is the best-fit equilibrium isotherm for the adsorption of adsorbates onto LS based on a linearized correlation coefficient. The largest adsorbed amounts (qmon) for the HA, FA, TA, and GA on LS were 2131, 1546, 1112, and 100 g/kg, respectively. Similarly, the qmon for the RB19, RO16, RB5, AO7, and AG27 were 5.67, 3.36, 2.87, 2.0, and 1.78 mol/kg, respectively. The qmon of the adsorption of Cu(II) on LS in aqueous solution was 1.32 mol/kg while that in aqueous containing citric acid was 2.07 mol/kg. The results revealed that the LS could effectively removed the Cu(II) from aqueous solution. Moreover, the adsorption kinetic data were analyzed with Intraparticle diffusion (ID) model, Elovich equation, and Pseudo-second-order (PSO) model. The experimental adsorption kinetic profiles are perfectly reproduced in the simulated data obtained from numerically on the basis of the PSO kinetic model. Thermodynamic parameters such as change in Gibbs free energy (∆G°), enthalpy (∆H°) and entropy (∆S°) were also discussed. The negative value of the ∆G° demonstrated that the adsorption process is favorable for the interaction cited and the pronounced LS-adsorbates interaction is reflected in the positive values of ∆H° (6.5~16.8 kJ/mol) and ∆S° (45.5 ~82.2 J/mol K).