粉煤灰负载壳聚糖吸附剂制备及其吸附性能研究

Preparation of Fly Ash Lord Chitosan and Its Study on Adsorption Performance

以粉煤灰为原料,通过负载壳聚糖制得一种新型吸附剂——粉煤灰/壳聚糖复合材料(fly ash/chitosan,FA/CTS),用SEM、XRD及FT-IR进行表征,探讨了一些重要的制备条件和吸附条件对其处理酸性红B(Acid red B,AR B)和活性艳红X-3B(Reactive brilliant red X-3B,RBR X-3B)染料吸附性能的影响,研究了吸附动力学,考察了复合吸附剂的再生.结果表明,当CTS与FA的质量比为1∶2.5时,所得FA/CTS对酸性红B和活性艳红X-3B的吸附量和去除率分别达345.74mg/g、225.68mg/g、92.32%和90.38%.染料起始浓度、pH、吸附时间和温度均对吸附有影响.在不同温度下,FA/CTS对AR B和RBR X-3B的吸附动力学均能用准二级吸附速率方程精确描述(R^2>0.999),吸附活化能分别为61.41kJ/mol和31.46kJ/mol,吸附具有吸热性质.复合吸附剂能用很稀的NaOH溶液再生,且可至少重复利用3~4次.FA负载CTS后对AR B和RBR X-3B的吸附性能比FA显著增强.

A new adsorbent,fly ash/chitosan（FA/CTS）composite materials,was prepared by loading chitosan onto fly ash and characterized by SEM,XRD and FT-IR.Effects of some important preparation conditions and adsorption conditions on the adsorption properties of FA/CTS for treating acid red B（AR B）and reactive brilliant red X-3B（RBR X-3B）were investigated.The adsorption kinetics was studied.The recycling of the adsorbent was investigated.The results show that the adsorption capacities and corresponding removal rates of AR B and RBR X-3Bonto FA/CTS are 345.74mg/g,225.68mg/g,92.32%and 90.38% respectively when the mass ratio of CTS and FA is 1∶2.5.Initial dye concentration,pH value,adsorption time and temperature are affected on the adsorption.The adsorption process is fit with the pseudo second-order kinetic equation（R^2〉0.999）at different temperatures.The obtained apparent activation energy is 61.41kJ/mol and 31.46kJ/mol for AR B and RBR X-3Brespectively.The adsorption is endothermic nature.Compared with FA,the adsorption capacities of FA/CTS composite for AR B and RBR X-3Bare significantly enhanced.The adsorbent can be regenerated by a very dilute NaOH solution and reused at least 4times and 3times for dye removal from the wastewater.