磁性沸石去除水中磷的性能和机理研究

发布时间：2018-05-09 11:19

本文选题：改性磁性沸石 + 磷　；参考：《合肥工业大学》2016年硕士论文

【摘要】：近年来,水体富营养化问题日趋严峻,成为亟待解决的环境问题之一。磷作为水体富营养化的限制性因子,对其含量控制尤为重要。吸附是一种去除水中磷的常用方法。本文以廉价天然沸石为吸附剂,通过有机改性和无机改性改善其吸附性能,同时,考虑吸附剂的回收再利用问题,制备有机磁性沸石和无机磁性沸石,并对磁性沸石的结构特性进行研究。通过有机磁性沸石和无机磁性沸石对磷的静态吸附和动态吸附实验,探讨其吸附磷的主要影响因素和吸附机理。首先,通过溶液浸渍法制备有机磁性沸石和无机磁性沸石,采用物理吸附仪(BET)、X射线衍射分析仪(XRD)、场发射扫描电镜(SEM)、傅里叶红外光谱仪(FT-IR)、X射线能谱仪(XPS)和电子顺磁共振波谱仪(EPR)对磁性沸石进行表征。结果表明,有机磁性沸石和无机磁性沸石均具有较高的比表面积,其比表面积大小：Mn-Zr-Fe磁性沸石Mn-Fe磁性沸石Zr-Fe磁性沸石PMA-Fe-Al磁性沸石TMA-Fe-Al磁性沸石BA-Fe-Al磁性沸石。有机磁性沸石和无机磁性沸石均具有较强的磁性,其中BA-Fe-Al、TMA-Fe-Al、PMA-Fe-Al、Zr-Fe、Mn-Fe和Mn-Zr-Fe磁性沸石的饱和磁化强度分别为31.9、26.2、24.8、29.9、18.6、22.4 emu/g。另外,天然沸石、BA-Fe-Al、TMA-Fe-Al、PMA-Fe-Al、Zr-Fe、Mn-Fe和Mn-Zr-Fe磁性沸石的零电荷点(pHzpc)分别为5.3、5.2、5.4、4.5、4.1、5.9、4.3。其次,采用有机磁性沸石和无机磁性沸石吸附磷,考察其对磷的吸附特性。结果表明,伪二级动力学模型和Langmuir等温模型更加适合描述有机磁性沸石和无机磁性沸石对磷的吸附过程。在308 K,磷初始浓度为35 mg/L时,BA-Fe-Al、 TMA-Fe-Al、PMA-Fe-Al、Mn-Fe、Zr-Fe和Mn-Zr-Fe磁性沸石对磷的平衡吸附量分别为6.8、7.1、9.7、11.8、8.8和20.9 mg/g。随着温度的升高,有机磁性沸石和无机磁性沸石对磷的吸附量随之增加。酸性环境有利于有机磁性沸石和无机磁性沸石吸附磷,碱性环境会削弱其对磷的吸附效果。BA-Fe-Al、TMA-Fe-Al、 PMA-Fe-Al、Mn-Fe、Zr-Fe和Mn-Zr-Fe磁性沸石吸附磷的最佳投加量分别为2.5、1.0、1.0、1.0、1.0、1.0 g/L。随着共存离子的浓度增加,有机磁性沸石和无机磁性沸石对磷的吸附量随之减少,其中Cl-对有机磁性沸石和无机磁性沸石吸附磷的影响最小,HCO3-对有机磁性沸石和无机磁性沸石吸附磷的影响最大。最后,对有机磁性沸石和无机磁性沸石的再生性能和动态吸附实验进行考察。结果表明,有机磁性沸石和无机磁性沸石具有较好的再生能力,并且可以多次循环利用。BA-Fe-Al、TMA-Fe-Al、PMA-Fe-Al、Mn-Fe、Zr-Fe和Mn-Zr-Fe磁性沸石经过六次吸附-脱附循环后,仍为第一次平衡吸附量的64.8%、75.1%、77.4%、66.7%、64.2%和76.8%。当进水磷浓度增大,有机磁性沸石和无机磁性沸石穿透点出现时所对应的有效处理体积随之减少。
[Abstract]:In recent years, eutrophication has become one of the most urgent environmental problems. Phosphorus, as a limiting factor of eutrophication, is very important to its content control. Adsorption is a common method for removing phosphorus from water. In this paper, cheap natural zeolites were used as adsorbents to improve their adsorption properties through organic modification and inorganic modification. At the same time, organic magnetic zeolites and inorganic magnetic zeolites were prepared by considering the problem of recovery and reuse of adsorbents. The structure characteristics of magnetic zeolite were studied. Through the static and dynamic adsorption experiments of phosphorus by organic magnetic zeolite and inorganic magnetic zeolite, the main influencing factors and adsorption mechanism of phosphorus adsorption were discussed. Firstly, organic magnetic zeolite and inorganic magnetic zeolite were prepared by solution impregnation. The magnetic zeolites were characterized by physical absorption spectrometer BETX X ray diffraction analyzer, field emission scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR) and electron paramagnetic resonance spectroscopy (EPR). The results show that both organic and inorganic magnetic zeolites have high specific surface area, the specific surface area of which is: Mn-Zr-Fe magnetic zeolite, Mn-Fe magnetic zeolite, Zr-Fe magnetic zeolite, PMA-Fe-Al magnetic zeolite, TMA-Fe-Al magnetic zeolite, BA-Fe-Al magnetic zeolite. Both organic and inorganic magnetic zeolites have strong magnetic properties, and the saturation magnetization of BA-Fe-Fe-AlMA-Fe-AlPMA-Fe-Zr-FeMn-Fe and Mn-Zr-Fe magnetic zeolites are 31.926.2 (24.829.9) and 18.6mu / g, respectively. In addition, the zero charge point of the natural zeolite BA-Fe-AlN TMA-Fe-Aln-PMA-Fe-Al-Zr-FeMn-Fe and Mn-Zr-Fe magnetic zeolites are 5.3V 5.44.5N 4.1L 5.9cu 4.3respectively. Secondly, organic magnetic zeolite and inorganic magnetic zeolite were used to adsorb phosphorus. The results show that the pseudo-second-order kinetic model and the Langmuir isothermal model are more suitable to describe the adsorption process of phosphorus on organic and inorganic magnetic zeolites. At 308K and initial phosphorus concentration of 35 mg/L, the equilibrium adsorption capacities of BA-Fe-Al, TMA-Fe-AlPMA-Fe-PMA-FeMn-FeOZr-Fe and Mn-Zr-Fe magnetic zeolites for phosphorus were 6.87.1C9.7C 11.88.8 and 20.9 mg / g, respectively. With the increase of temperature, the amount of phosphorus adsorbed by organic magnetic zeolite and inorganic magnetic zeolite increased. Acidic environment is favorable to the adsorption of phosphorus by organic magnetic zeolite and inorganic magnetic zeolite, while alkaline environment will weaken the adsorption effect of phosphorus. The optimum dosages of PMA-Fe-Al Mn-FeZr-Fe and Mn-Zr-Fe magnetic zeolites for phosphorus adsorption are 2.5g / L, 1.0g / L, 1.0g / L and 1.0g / L, respectively, for PMA-Fe-AlN TMA-Fe-Al, PMA-Fe-AlnFeZr-Fe and Mn-Zr-Fe magnetic zeolites. With the concentration of coexisting ions increasing, the amount of phosphorus adsorbed by organic magnetic zeolite and inorganic magnetic zeolite decreased. The effect of Cl- on the adsorption of phosphorus on organomagnetic zeolite and inorganic magnetic zeolite is the least. HCO3- has the greatest effect on the adsorption of phosphorus on organomagnetic zeolite and inorganic magnetic zeolite. Finally, the regeneration performance and dynamic adsorption of organic magnetic zeolite and inorganic magnetic zeolite were investigated. The results show that the organic magnetic zeolite and the inorganic magnetic zeolite have good regeneration ability, and can be reused for several times. After six adsorption-desorption cycles, the organic magnetic zeolite and the inorganic magnetic zeolite are still 64.85.177.47.47.46.76.77.76.74.2% and 76.882% of the first equilibrium adsorptive capacity after six adsorption-desorption cycles. The results show that the organic magnetic zeolite and the inorganic magnetic zeolite have good regeneration ability and can be reused for several times. The results show that the organic magnetic zeolites and the inorganic magnetic zeolites are still 64.2% and 76.882% respectively after six adsorption-desorption cycles. The effective treatment volume of organic magnetic zeolite and inorganic magnetic zeolite decreased with the increase of phosphorus concentration in the influent.
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：X52

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