3O4磁性納米顆粒,利用SiO2、羧甲基-β-環(huán)糊精(CM-β-CD)對(duì)磁性顆粒的表面進(jìn)行修飾,制備了具有高吸附性能的Fe3O4基磁性納米材料(Fe3O4@SiO2@CM-β-CD),開(kāi)展了單因素優(yōu)化實(shí)驗(yàn),通過(guò)TEM、Mapping、EDS、BET等手段對(duì)磁性納米復(fù)合材料的物化特性進(jìn)行表征,探討了Fe3O4@SiO2@CM-β-CD對(duì)稀土Er(Ⅲ)的吸附行為。結(jié)果表明:十二烷基苯磺酸鈉(SDBS)的投加量為1 g,正硅酸四乙酯(TEOS)的投加量6 mL,氨丙基三乙氧基硅烷(APTES)的投加量為1 mL,CM-β-CD投加量為0.5 g時(shí),Er(Ⅲ)去除率最高,可達(dá)到95%以上。進(jìn)一步探究了吸附劑投加量、溫度及轉(zhuǎn)速對(duì)Er(Ⅲ)去除率的影響。結(jié)果發(fā)現(xiàn),當(dāng)接觸時(shí)間為30 min,初始Er(Ⅲ)濃度為10 mg/L,初始pH為4.5,吸附劑用量為 30 mg,溫度為298 K,轉(zhuǎn)速為150 r/min時(shí),Er(Ⅲ)的去除率約為98%。將吸附Er(Ⅲ)后的納米材料用0.1 mol/L HNO3進(jìn)行解吸,解吸20 min,Er(Ⅲ)的解吸率可達(dá)87%以上。采用XPS分析手段對(duì)Fe3O4@SiO2@CM-β-CD吸附機(jī)制進(jìn)行了初步探究。結(jié)果表明,F(xiàn)e3O4@SiO2@CM-β-CD對(duì)Er(Ⅲ)的吸附以環(huán)糊精空腔的包和作用為主,靜電吸附、化學(xué)吸附為輔。本研究可為水溶液中低濃度稀土元素的高效回收提供新方法。;Fe3O4 magnetic nanoparticles were prepared by co-precipitation method, the surface of the magnetic particles was modified by SiO2 and CM-β-CD, and Fe3O4-based magnetic nanomaterials (Fe3O4@SiO2@CM-β-CD) with high adsorption properties were prepared. Single factor optimization experiments were carried out, and the physical and chemical properties of magnetic nanocomposites were characterized by TEM, EDS and BET. The adsorption behavior of Fe3O4@SiO2@CM-β-CD on rare earth Er(Ⅲ) was investigated. The effects of adsorbent dosage, temperature and rotational speed on erbium removal rate were also investigated. The results show that when the dosage of SDBS is 1 g, the dosage of TEOS is 6 mL, the dosage of APTES is 1 mL, and the dosage of CM-β-CD is 0.5 g, the adsorption rate of Er(Ⅲ) can preferably reach more than 95%. When the contact time is 30 min, the initial concentration of Er(Ⅲ) is 10 mg/L, the initial pH is 4.5, the dosage of adsorbent is 30 mg, the temperature is 298 K, and the rotational speed is 150 r/min, the removal rate of Er(Ⅲ) is about 98%. After the adsorption of erbium, the nanomaterials were desorbed with 0.1 mol/L HNO3 for 20 min, and the desorption efficiency of rare earth Er(Ⅲ) can be more than 87%. The adsorption mechanism of Fe3O4@SiO2@CM-β-CD was investigated by XPS analysis. It is found that the adsorption of Fe3O4@SiO2@CM-β-CD on Er(Ⅲ) is mainly by the inclusion of cyclodextrin cavity, supplemented by electrostatic adsorption and chemisorption. The results of this study can provide a new method for efficient recovery of rare earth elements with low concentration in aqueous solution."/>
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