坡缕石-活性炭-壳聚糖负载环糊精对硝基苯酚的吸附性质

研究了坡缕石-活性炭-壳聚糖负载环糊精吸附剂对对硝基苯酚、邻硝基苯酚的吸附行为以及pH、温度等对吸附的影响。在pH=5.0-7.5时,自制吸附剂对对硝基苯酚,邻硝基苯酚具有较好的吸附作用。等温吸附曲线拟合结果显示,吸附剂对硝基苯酚的吸附更符合Langmu ir方程。热力学函数计算表明,吸附剂对硝基酚的吸附是自发的放热过程,对硝基苯酚的吸附热和熵变分别为-27.49 kJ/mol和-70.39 J/(mol.K),邻硝基苯酚的吸附热和熵变分别为-29.06 kJ/mol和-78.87 J/(mol.K),吸附自由能均随温度的升高而增加。

Adsorption Properties of Palygorskite/Active Carbon/Chitosan Supported Cyclodextrin Adsorbent for Nitrophenols

The adsorption behavior of p-nitrophenol and o-nitrophenol on the adsorbent of palygorskite/active carbon/chitosan supported cyclodextrin was studied.Effects of acidity and temperature were examined.The adsorbent has a good adsorption capacity at pH of 5.0～7.5.Thermodynamic study shows that the adsorption process can be well simulated by the Langmuir isothermal equation.Thermodynamic function calculation shows that the adsorption is a spontaneous and exothermic process.Enthalpy and entropy change of the adsorption of p-nitrophenol are-27.49 kK/mol and-70.39 J/(mol·K),respectively.Enthalpy and entropy change of the adsorption of o-nitrophenol are29.06 kJ/mol and-78.87 J/(mol·K),respectively.Free energy of the adsorption increases with the increase of temperature.