茶叶质铁的吸附性能及动力学研究

研究了改性茶叶对Fe3+的吸附性能及吸附动力学。探讨了溶液的初始浓度、pH值、时间和温度对吸附性能的影响,并采用Langmuir等温吸附方程和准二级动力学吸附速率方程探讨了等温吸附过程和吸附动力学过程。结果表明:改性茶叶对Fe3+吸附时,溶液最佳pH为0.8~0.9之间,Fe3+初始浓度大于1.40 mol/L,吸附温度范围为50~60℃,吸附60 min基本达到饱和;改性茶叶吸附Fe3+的吸附规律符合Langmuir等温吸附方程,在不同初始浓度下,改性茶叶吸附Fe3+的吸附过程符合准二级动力学吸附速率方程,活化能为Ea=12.73 kJ/mol,该吸附行为是一个吸热过程。

Study on Adsorption Properties and Kinetics of Tea-Fe(Ⅲ)

The adsorption properties and kinetics of Fe~3+ by modified tea were studied.The effects of the initial concentration,pH,time and temperature on adsorption capacity were investigated.The adsorption process could be described by Langmuir equation.The kinetics for adsorption at different concentration were investigated by quasi-second dynamic equation.The results indicated that the optimum conditions were: pH=0.8～0.9,the temperature was 50～60 ℃ and soaking time was 60 min,when the initial concentration was more than 1.40 mol/L.The adsorption data of Fe~3+ ions on modified tea showed a good fit with Langmuir isotherm equation.The dynamic adsorption model of Fe~3+ ions on modified tea accorded with quasi-second dynamic equation. The activation energy(Ea) was 12.73 kJ/mol,suggesting that the adsorption was endothermic.