交联淀粉微球对对硝基苯酚的吸附行为及机理研究

Study on Adsorption Behavior and Mechanism of p-nitrophenol by Crosslinked Starch Microspheres

以可溶性淀粉为原料,N,N′-亚甲基双丙烯酰胺为交联剂,采用反相悬浮聚合得到了一种交联淀粉微球(CSM),研究了CSM对对硝基苯酚(p-NP)的静态吸附行为,测定了吸附等温线,分析了吸附热力学性质和动力学特征,并用红外光谱仪和X射-线衍射仪对CSM吸附p-NP前后对照分析,探讨吸附机理。结果表明,在研究范围内,CSM对p-NP的吸附等温线同时符合Langmuir等温方程和Freundli-ch等温方程;在不同温度下,CSM吸附p-NP的吸附焓变(ΔH)、熵变(ΔS)、吉布斯函变(ΔG)均为负值,吸附过程自发、放热,且为焓推动作用。

The crosslinked starch microspheres（CSM） were synthesized from soluble starch by inverse suspension polymerization with N,N′-methylenebisacrylamide as crosslinker.The static adsorption behavior of CSM for p-nitrophenol was investigated,the isotherms were measured,and the adsorption thermodynamics and kinetics characteristics were researched.The structures of CSM before and after adsorption were characterized by FT-IR spectroscopy and X-ray diffraction（XRD）,and the mechanism of adsorption was also discussed.The result showed that within the framework of the study,the Langmiur and Freundlich adsorption isotherm equations were adapted for the adsorption characteristic of CSM for p-nitrophenol.The enthalpy change（ΔH）,entropy change（ΔS） and free energy change（ΔG） for p-nitrophenol adsorbed by CSM were all negative at different temperatures.The adsorption was a spontaneous,exothermic and enthalpy promoting process.