粉煤灰负载壳聚糖对磷吸附的热力学研究 -

以粉煤灰负载壳聚糖作为吸附剂,在静态吸附条件下,研究了其对磷的吸附行为,并对吸附过程的热力学进行了分析。结果表明,吸附平衡数据都能够较好地符合Langmuir和Freundlich吸附等温方程,但Langmuir方程能够更好地描述吸附等温线。在20～35℃范围内,磷在粉煤灰负载壳聚糖上的吸附是一个吸热过程,反应的吉布斯自由能变小,同时伴随着熵值的增加,吸附焓变为44.36 kJ/mol。 A kind of adsorbent is made by coating chitosan on the surface of fly ash,study the adsorption efficiency of phosphorus under static conditions as well as the thermodynamics of the adsorptions.Equilibrium datas preferably follow the Langmuir and Freundlich model,while the Langmuir isotherm model reflect the isotherm data better than the Freundlich isotherm model.The phosphorus adsorption by the fly ash-chitosan adsorbent is endothermic in nature and is accompanied with an increase in entropy and a decrease in gibbs energy ranging from 20 ℃ to 35 ℃,and the numerical values of sorption gibbs energy is 44.36 kJ/mol