【摘要】 以可生物降解的壳聚糖为原料,采用超声乳化-化学交联法制备了具有空腔结构的壳聚糖微球;采用扫描电子显微镜对微球的形貌和大小进行了表征;采用紫外-可见光谱仪和红外光谱仪研究了壳聚糖微球对甲基橙的吸附动力学和热力学,并对吸附机理进行了初步探讨。结果表明,壳聚糖微球外形为比较规整的球形,粒径为1~10μm,粒度分布均匀,具有空腔结构。壳聚糖微球对甲基橙的吸附过程受甲基橙初始浓度、pH值和温度等因素的影响;当pH=7.25、温度为298 K时,壳聚糖微球对甲基橙的吸附率达99.34%;该吸附过程为具有化学吸附的自发过程,与Freund lich等温吸附模型相吻合(R=0.9974)。更多还原

【Abstract】 With biodegradable chitosan as raw material,chitosan microsphere with vacuum structure is prepared by means of ultrasonic emulsifying-chemical crosslinking method.Morphology and dimension of microsphere are characterized by scanning electron microscopy(SEM),adsorption kinetics and thermodynamics of chitosan microsphere to methyl orange is studied by ultraviolet-visible spectrophotometers and infrared spectrophotometers,adsorption mechanism is briefly discussed.Results show that microsphere shape is regular with size ranging from 1 to 10 μm.Factors of initial concertration of methyl orange,pH value and temperature play a significant role on adsorption.It is observed that adsorption efficiency of methyl orange is 99.34% at pH value 7.25 and 298 K.The Langmuir and Freundlich adsorption models are applied to describe the equilibrium isotherms.The Freundlich model agreed very well with experimental data(R = 0.997 4).The negative values of ΔG~0 indicate that overall adsorption process is spontaneous.The IR spectra indicate that the adsorption process contains chemical adsorption.更多还原