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  本文關鍵詞： 磁性 果汁殘渣 吸附 重金屬 染料　出處：《山東農業(yè)大學》2015年碩士論文　論文類型：學位論文

【摘要】：本文以農產品廢棄物-果汁殘渣作(JR)為基本的吸附材料,與具有磁性的納米Fe3O4通過三聚磷酸鈉的交聯(lián)作用合成了新型具有磁性的果汁殘渣吸附劑(MJR),并通過FT-IR、BET、XRD、Zeta電位、磁化強度對其進行了表征。以常見的重金屬Pb(II)和陰離子染料孔雀綠(MG)作為目標污染物,通過批量實驗,研究了p H、吸附劑量和接觸時間對吸附過程的影響,探究了最佳吸附條件。利用了準二次動力學模型、內部擴散動力學模型、Langmuir等溫線模型、Freundlich等溫線模型、D-R等溫線模型,對批量實驗得到的實驗數(shù)據(jù)進行模型的擬合,揭示出吸附作用機理。并通過磁性實驗,實現(xiàn)吸附劑與吸附質的快速分離。本文得出以下幾點結論:(1)FT-IR紅外分析表明,JR的3250 cm-1波峰轉移到MJR的3370 cm-1處,且波峰的強度增大,MJR的1055 cm-1處波峰也顯著增強,說明通過磁性改良后不僅沒減少JR表面官能團,反而增強了其官能團,有助于增強吸附能力。BET分析測得JR的比表面積為4.33 m2/g,MJR的比表面積為1.88 m2/g,說明通過磁性Fe3O4改性后,由于Fe3O4粒子填充了JR的部分孔徑,導致其比表面積的降低。XRD分析測定制備的磁性氧化鐵的六個特征峰(2θ=30.18°、35.65°、43.36°、53.62°、57.01°和62.83°)分別為Fe3O4的六個反射平面,證明了氧化鐵成分為磁鐵礦(Fe3O4)。Zeta電位表明,在同一pH條件下,MJR表面的負電性比JR的負電性更強,暗示著MJR對帶正電的陽離子有較強的靜電吸引作用。磁化強度分析表明,通過磁滯曲線可以得出Fe3O4和MJR的飽和磁化強度分別為61.6和20.5 emu/g,揭示了果汁殘渣已經被成功的磁化,具有較高的順磁性且磁感應性較強,且足以通過外加磁場使其快速分離。(2)通過批量實驗,得出MJR吸附Pb(II)和MG的最佳實驗條件分別為122.5 min、5.06 g/L、6.10和66.69 min、5.14 g/L、6.06。(3)通過模型擬合表明,MJR吸附Pb(II)過程既符合Langmuir等溫線模型,又符合Freundich等溫線模型。MJR吸附MG過程符合Langmuir等溫線模型,但不符合Freundich等溫線模型。MJR吸附Pb(II)和MG的最大比吸附量分別為48.74、106.24 mg/g。(4)進行了磁性分離實驗,在外加磁場的條件下,MJR實現(xiàn)固液分離只需要30秒,大大縮短的固液分離時間。
[Abstract]:In this paper, a new magnetic adsorbent, MJRN, was synthesized by the cross-linking reaction of sodium tripolyphosphate with the magnetic nanometer Fe3O4 using the residue of agricultural products and fruit juice as the basic adsorption material, and the Zeta potential of the adsorbent was obtained by FT-IRN BET-XRDU. It was characterized by magnetization. The effects of pH, amount of adsorbent and contact time on the adsorption process were studied by batch experiments with the common heavy metal PbCII) and the anionic dye malachite green (MG) as the target pollutants. The optimal adsorption conditions were investigated. The quasi quadratic kinetic model and the internal diffusion kinetic model were used to simulate the Freundlich isotherm model and the D-R isotherm model. The mechanism of adsorption was revealed, and the rapid separation of adsorbent and adsorbate was realized by magnetic experiment. The following conclusions were obtained in this paper: the 3250 cm-1 peak of JR was transferred to 3370 cm-1 of MJR by FT-IR analysis. The intensity of the wave peak increased significantly at 1055 cm-1 of MJR, which indicated that the magnetic modification not only did not decrease the surface functional group of Jr, but also enhanced its functional group. The specific surface area of JR is 4.33 m ~ (-2) / g ~ (-1) m ~ (2 / g), which is 1.88 m ~ (2 / g) by magnetic Fe3O4 modification, which indicates that, after modification by magnetic Fe3O4, the partial pore size of Jr is filled with Fe3O4 particles, and the specific surface area of JR is 4.33 m ~ (-2) / g ~ (-1). The results show that the six characteristic peaks of magnetic ferric oxide prepared by XRD analysis are the six reflection planes of Fe3O4, respectively. The results show that the composition of ferric oxide is magnetite Fe _ 3O _ 4 路Zeta potential, which indicates that the six characteristic peaks of magnetic iron oxide are 36.18 擄~ 35.65 擄/ 43.36 擄/ 53.62 擄/ 57.01 擄and 62.83 擄, respectively, and the results show that the magnetic ferric oxide is composed of Fe _ 3O _ 4, Fe _ 3O _ 4 and Fe _ 3O _ 4. At the same pH, the negative electric property of MJR surface is stronger than that of JR, suggesting that MJR has a strong electrostatic attraction to positive cations. The saturation magnetization of Fe3O4 and MJR are 61.6 and 20.5emu / g, respectively. The results show that the juice residue has been magnetized successfully and has high paramagnetism and strong magnetic induction. The optimum experimental conditions for MJR adsorption of PBII) and MG were 122.5 min / L 6.10 and 66.69 min / L 5.14 g / L ~ (6.06.3) respectively. The results of model fitting showed that the process of PbIIs adsorption was in accordance with the Langmuir isotherm model. Freundich isotherm model. MJR adsorption process accords with Langmuir isotherm model, but not with Freundich isotherm model. The maximum specific adsorption capacity of MG and MJR isotherm model is 48.74mg / g 路g 路mg. Under the condition of external magnetic field, it takes only 30 seconds to realize solid-liquid separation by MJR, which greatly shortens the time of solid-liquid separation.
【學位授予單位】：山東農業(yè)大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：X791

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本文編號：1524262