【摘要】 粉煤灰(Fly ash,FA)经高温焙烧制得活化FA(Activated FA,AFA),又经溶液反应引入少量Fe和壳聚糖(Chitosan,CTS)制得Fe/CTS/AFA复合材料,将其直接用于水体中直接湖蓝5B(Direct sky blue 5B,DSB 5B)和活性翠蓝KN-G(Reactive turquoise blue KN-G,RTB KN-G)染料的吸附,通过研究影响吸附的主要因素、吸附动力学和等温吸附,并结合材料的FT-IR分析,详细探讨了材料的吸附性能。结果表明,水体酸度是影响吸附剂性能的最主要因素。当吸附剂投加量为0.1g、溶液pH值为2.0时,于25℃下吸附60min即可达吸附平衡,Fe/CTS/AFA对DSB 5B和RTB KN-G具有很强的吸附能力,吸附量分别可达635mg/g和906mg/g,比FA分别增大了31.6倍和15.3倍。吸附过程均能用准二级吸附动力学方程精确描述,等温吸附数据完全符合Langmuir模型。热力学参数吸附自由能变的负值、焓变和熵变为正值表明Fe/CTS/AFA对DSB 5B的吸附为界面上有序性降低的自发吸热过程。吸附饱和RTB KN-G的Fe/CTS/AFA可用0.01mol/L NaOH溶液再生,可至少重复使用三次。FT-IR结构分析表明Fe/CTS/AFA已成功制得,并且对高浓度染料废水具有高效净化能力。更多还原

【Abstract】 Fe/CTS/AFA composite,prepared by the high-temperature calcination of fly ash(the activated FA,AFA)and the reaction solution with a small amount of Fe(Ⅲ)and chitosan(CTS),was used for the adsorption of Reactive turquoise blue KN-G(RTB KN-G)and Direct sky blue 5 B(DSB 5 B)dyes from aqueous solutions.The adsorption property of the composite was discussed by studying main factors affecting the adsorption,dynamics,thermodynamics and structural analysis of FT-IR.The results revealed that the adsorbent performance was strongly dependent on the solution pH.Fe/CTS/AFA composite had excellent adsorption performance for RTB KN-G and DSB 5 Bwith the adsorption amounts of 906 mg/g and 635 mg/g under the conditions of the dosage of0.1 g at 25℃and solution pH of 2.0,which were 31.6 and 15.3 times those of FA,respectively.The adsorption equilibrium can be achieved in 60 min.The adsorption processes for two dyes can be accurately described by the pseudo-second-order adsorption model.Isothermal adsorption data completely accorded with the Langmuir model.Thermodynamic parameters,negative value of Gibbs free energy changes and positive values of enthalpy changes and entropy changes,illustrated that the adsorption of DSB 5 Bby Fe/CTS/AFA was spontaneous and endothermic nature accompanied by decreasing in order on the liquid-solid interface.Fe/CTS/AFA adsorbent saturated by RTB KN-G dye can be regenerated by 0.01 mol/L NaOH solution,and reused 3 times for dye removal from the wastewater.According to the activation energy values obtained by Arrhenius equation and the effect of temperature on the adsorption,it can be inferred that the adsorption was mainly electrostatic and physical action.FT-IR structure analysis demostrated that Fe/CTS/AFA had been successfully prepared and can be used for the effective purification of high-concentration dye wastewater.更多还原