负载亚铁氰化钴钾废弃皮革吸附剂对Rb(I)的吸附

Adsorption of Rb (Ⅰ) with Potassium Cobalt Ferrocyanide Loaded on Waste Leather

摘要:

将亚铁氰化钴钾负载于经碱水解后的废弃皮革上，制备了一种铷离子吸附剂。采用扫描电子显微镜（SEM）、傅里叶变换红外光谱（FT-IR）、X-射线光电子能谱（XPS）和X-射线衍射（XRD）等对其进行了表征。考察了Co(NO3)2•6H2O和K4Fe(CN)6•3H2O的质量比、溶液pH、铷离子（Rb+）初始质量浓度、吸附剂用量和接触时间对吸附效果的影响。结果表明：m〔Co(NO3)2•6H2O〕:m〔K4Fe(CN)6•3H2O〕=3:4时，制备的0.09 g吸附剂对pH为7、初始质量浓度为20 mg/L 的Rb+溶液的吸附率为93.55% ，且于6 h达吸附平衡。探究发现，Langmuir等温吸附模型和准二级动力学模型能更好地描述Rb+在吸附剂上的吸附行为。以1.5 mol/L KCl作为脱附剂，脱附率达90%以上。将该吸附剂用于提取盐湖卤水中的Rb+，当pH=7时，吸附率为51.19%，该吸附剂具有潜在的实用价值。

Abstract:

otassium cobalt ferrocyanide was loaded on alkali-hydrolyzed waste leather to prepare a kind of adsorbent for Rb+ adsorption, whose structure and morphology were characterized with scan electron microscope (SEM), fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). The effects of the mass ratio of Co(NO3)2•6H2O and K4Fe(CN)6•3H2O, pH, initial Rb+ mass concentration, adsorbent dosage, and contact time on adsorption capacity of adsorbent for Rb+ were investigated. The results showed that the adsorbent presented higher adsorption capacity for Rb+ when the mass ratio was 3:4. The adsorption efficiency was 93.55% at pH 7, adsorbent dosage of 0.09 g and initial Rb+ mass concentration of 20 mg/L, and adsorption achieved equilibrium at 6 h. The isothermal and kinetics of Rb+ adsorption on KCoFC-AWL were fitted well with Langmuir isotherm model and pseudo-second-order kinetics model. Up to 90% desorption efficiency of Rb+ was achieved with 1.5 mol/L KCl. The adsorption efficiency reached up to 51.19% when the adsorbent was utilised to adsorb Rb+ from saline lake at pH 7, indicating its potential application advantages as an efficient adsorbent.