| A large number of adsorption active sites were contained on the tea, such as-OH,=NH,> C=C<,> C=O,2-aza-ring and multi-phenols, etc.. These groups reacted with metal ions in appropriate conditions, for example, metal ions could be adsorbed on the tea. Metal ions also could be precipitated because of polyhydric phenol with active hydroxyl. The physical and chemical adsorption capacities were enhanced after treated with phenolic formaldehyde condensation by formaldehyde. The main content was described as follows:adsorption kinetics, adsorption thermodynamics and the adsorption conditions of Fe3+ with modified tea, The new kind of adsorbent of Tea-Fe(Ⅲ) was synthesized under suitable condition. In addtion adsorption capacity, adsorption activation energy and adsorption thermodynamic parameters were studied on industrial wastewater (phenol wastewater naphthol wastewater, Reactive Yellow K-6G wastewater and Reactive Brilliant Red K-2BP wastewater) removal using Tea-Fe(Ⅲ). The main results obtained were as follows: 1. Investigation of modified tea on adsorption capacity, adsorption kinetics and adsorption thermodynamics with Fe3+The optimal conditions were the initial concention of Fe3+ larger than 1.40 mol/L, the reaction temperature 50-60℃, pH 0.8-0.9; adsorption 60 min reaching to saturation, the saturated adsorption capacity 863mg/g. The adsorption behavior of modified tea with Fe3+ showed a good fit with Langmuir isotherm equation, Thermodynamic parameters of Gibbs free energy(AG) was less than zero. Enthaly of adsorption (AH) value was 340.61J/mol and the entropy (ΔS) value was 1.18 J/mol·K. The dynamic adsorption model of modified tea on Fe3+ ions was well accorded with quasi-second dynamic equation. The activation energy (Ea) was determined to be only 28.74 kJ/mol, indicated that the adsorption is endothermic process.2. Investigation of adsorption capacity, adsorption kinetics and adsorption thermodynamics of simulated phenol wastewater onto Tea-Fe(Ⅲ)The optimum conditions of adsorption technology were as follows: pH 9.0, the temperature 50℃, adsorption time 60 min. If the initial concention of phenol wastewater was 200mg/L, the saturated adsorption capacity was 4.78 mg/g on the above conditions. The adsorption behavior of Tea-Fe(Ⅲ) with phenol shows a good fit with Langmuir isotherm equation, Thermodynamic parameters of Gibbs free energy(ΔG) was less than zero. Enthaly of adsorption (ΔH) value was 38.10 kJ/mol and the entropy (ΔS) value was 0.15 kJ/mol·K. The dynamic adsorption model of Tea-Fe(Ⅲ) on phenol was accorded with the character of the second-order reaction, and the activation energy (Ea) was determined to be 92.04 kJ/mol.3. Investigation of adsorption capacity, adsorption kinetics and adsorption thermodynamics of simulated naphthol wastewater onto Tea-Fe(Ⅲ)The optimum conditions of adsorption technology were as follows: pH 11.0, the temperature 50℃, adsorption time 120min. If the initial concention of phenol wastewater were 900 mg/L, the saturated adsorption capacity was 21.24 mg/g on the above conditions. The adsorption behavior of Tea-Fe(Ⅲ) with naphthol shows a good fit with Langmuir isotherm equation, Thermodynamic parameters of Gibbs free energy(ΔG) was less than zero. Enthaly of adsorption (ΔH) value was 9.86 kJ/mol and the entropy (ΔS) value was 0.053 kJ/mol·K. The dynamic adsorption model of Tea-Fe(Ⅲ) on naphthol was accorded with the character of the second-order reaction, and the activation energy (Ea) was determined to be 35.49 kJ/mol.4. Investigation of adsorption capacity, adsorption kinetics and adsorption thermodynamics of simulated Reactive Yellow K-6G wastewater onto Tea-Fe(Ⅲ) The optimum conditions of adsorption technology were as follows: pH 0.5, the reaction temperature 60℃, adsorption time 11h. If the initial concention of Reactive Yellow K-6G wastewater was 500 mg/L, the saturated adsorption capacity was 23.56 mg/g on the above conditions. The adsorption behavior of Tea-Fe(Ⅲ) with Reactive Yellow K-6G shows a good fit with Langmuir isotherm equation. Thermodynamic parameters of Gibbs free energy(ΔG) was less than zero. Enthaly of adsorption (ΔH) value was 57.12 kJ/mol and the entropy (ΔS) value was 0.22 kJ/mol·K. The dynamic adsorption model of Tea-Fe(Ⅲ) on Reactive Yellow K-6G was accorded with the character of the first-order reaction, and the activation energy (Ea) was determined to be 48.91 kJ/mol.5. Investigation of adsorption capacity, adsorption kinetics and adsorption thermodynamics of simulated Reactive Brilliant Red K-2BP wastewater onto Tea-Fe(Ⅲ)The optimum conditions of adsorption technology were as follows: pH 0.8, the reaction temperature 50℃, adsorption time 120 min. If the initial concention of Reactive Brilliant Red K-2BP wastewater 2000mg/L, the saturated adsorption capacity was 95.32 mg/g on the above conditions. The adsorption behavior of Tea-Fe(Ⅲ) with Reactive Brilliant Red K-2BP shows a good fit with Langmuir isotherm equation. Thermodynamic parameters of Gibbs free energy(ΔG) was less than zero. Enthaly of adsorption (ΔH) value was 16.49 kJ/mol and the entropy (ΔS) value was 0.074 kJ/mol·K. The dynamic adsorption model of Tea-Fe(Ⅲ) on Reactive Brilliant Red K-2BP was accorded with the character of the first-order reaction, and the activation energy (Ea) was determined to be 44.13 kJ/mol.
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