竹炭对碱性品红的吸附热力学和动力学研究.doc


竹炭对碱性品红的吸附热力学和动力学
研究#
郭恺泽,朱仙弟,王萍晓,赵松林**
(台州学院医药化工学院,浙江台州 317000)
摘要:采用静态吸附实验,研究了竹炭在水溶液中对碱性品红(FB)的吸附热力学性质与
动力学特性,同时对其吸附机理进行了一定程度的探讨。研究发现,随着初始浓度的增大、
温度升高、pH 升高,吸附量增大。吸附热力学和动力学结果表明,竹炭对 FB 的吸附是吸
热、自发过程,吉布斯自由能在- 到- kJ·mol-1 之间,以物理吸附为主,吸附行为
可用 Langmuir 方程描述;过程符合伪二级动力学和颗粒内扩散方程,吸附速率大小除受颗
粒内扩散过程控制外,还受液膜扩散和表面吸附过程的控制。
关键词:竹炭;碱性品红;吸附;热力学;动力学
中图分类号:X703
文献标识码:A
Adsorption thermodynamics and ics of Fuchsin Basic
on bamboo charcoal
GUO Kaize, ZHU Xiandi, WANG Pingxiao, ZHAO Songlin
(School of Pharmaceutics and Chemical Engineering, Taizhou University,
ZheJiang TaiZhou 317000)
Abstract: The adsorption ics, thermodynamics and mechanism of Fuchsine Basic (FB) over
bamboo charcoal were discussed based on the static adsorption data. The Results showed that the
adsorption capacity increases with the increasing the initial concentration, pH value, and
temperature. The isotherm data were well-correlated using a multi-temperature Langmuir model.
Thermodynamic parameters indicated that adsorption was a feasible, spontaneous (the variables of
Gibbs free energy (ΔG) is about -−- kJ·mol-1), and endothermic process, and suggested
that the process was mainly physisorption but chemisorption was also involved. Pseudo
second-order ics and intra-particle diffusion rate equation can be used to interpret the
adsorption ics. Adsorption rate is not only controlled b