石墨烯对含磷阻燃剂废水的吸附研究

发布时间：2018-05-29 19:14

本文选题：石墨烯 + 阻燃剂　；参考：《江苏大学》2017年硕士论文

【摘要】：伴随着现代化的快速进展,各种发明、技术给人类生活带来了极大的大量的便利,例如说新型磷系阻燃剂的应用。然而含磷阻燃剂在得到应用发展的同时,产生的磷系阻燃剂废水被排入到我们的环境中,给地球的环境产成了及其恶劣的影响,已经危及人类的生存环境。在污水治理的诸多方法、工艺中,吸附法因为具有一系列的特点,比如操作简易、吸附效率高、成本相对较低、对环境不易产生二次污染等突出的优点而被广泛应用于环境治理中。石墨烯是2004年在实验室中被首次发现和研制出来,之后因石墨烯具备上述优异的优点,已经在吸附领域展现出非常巨大的发展前景。选取天然鳞片状石墨粉作为本论文的原材料料,选择改良的Hummers氧化法并利用超声处理制备得到氧化石墨烯,选取水合肼作为还原剂,还原制得石墨烯;利用X射线衍射、拉曼光谱、傅里叶红外光谱和BET比表面积等物理、化学表征手段对材料的结构、官能团及形态学等特征进行了研究比较,分析制备得到的吸附剂的结构与性质,对吸附剂进行表征;研究石墨烯和其他几种经典的吸附剂对含磷阻燃剂模拟废水的吸附行为,并对静态吸附行为进行热力学、动力学拟合,对动态吸附行为进行拟合、探究。结论如下:(1)比较氧化石墨烯(GO)、单壁碳纳米管(SWCNT)、活性炭(AC)和石墨烯(G)对磷酸三丁酯(TBP)模拟废水的静态吸附性能。结果表明,G的吸附性能更好,随着反应接触时间、反应温度、pH和TBP初始浓度的增加,吸G对TBP吸附容量逐渐增加。采用准一级、准二级吸附动力学模型以及粒子内扩散模型对吸附剂吸附TBP阻燃剂废水的吸附过程进行拟合分析,拟合结果表明对TBP的吸附过程更符合准二级动力学模型,吸附属于化学吸附。利用Langmuir和Freundlich热力学模型对吸附剂吸附TBP过程进行拟合分析;拟合发现Langmuir模型能够更加准确地拟合石墨烯吸附TBP的热力学过程,在阻燃剂废水处理中有非常大的应用前景。(2)比较氧化石墨烯(GO)和石墨烯材料(G)对磷酸三甲苯酯(TCP)模拟废水的静态吸附性能。结果表明,G对TCP模拟废水的吸附效果要明显优于GO。随着反应接触时间、TCP初始浓度、温度增加,吸附剂吸附容量逐渐增加,腐殖酸对G吸附TCP的行为有显著的影响,而废水中金属离子的存在对吸附几乎没有大的影响。模型拟合结果表明,G吸附TCP的行为更符合准二级动力学模型,而Langmuir热力学模型能够更加准确地拟合G吸附TCP模拟废水的热力学过程。另外研究了实验数据的热力学参数结果表明,吸附属于吸热过程,吸附反应可自发进行。(3)探究了石墨烯对TCP模拟废水的动态吸附性能。通过控制变量法,比较了石墨烯吸附柱柱高、TCP模拟废水进水初始浓度、TCP废水运行流速等吸附条件的改变对G吸附TCP的动态吸附性能的影响;实验表明:随着TCP模拟废液进水流速增加,G吸附柱床层穿透会出现明显加快的现象,穿透时间点提前到来;随着TCP模拟废水初始浓度的增加,动态吸附穿透时间逐渐减少,得到的穿透曲线更加清晰;当G吸附柱的高度发生变化时,G对TCP模拟废水动态吸附行为的穿透时间和吸附的饱和时间都发生了变化。当吸附柱柱高分别从为1cm增加到2cm、3cm时,G对TCP模拟废水动态吸附行为的穿透分别从开始于30min、50min和100min,吸附饱和时间点分别发生在为230min、290min和330min。采用Thomas和Yoon-Nelson两种动态吸附模型对G吸附TCP模拟废水的动态吸附行为进行拟合;结果显示,相比较于Yoon-Nelson动态模型,Thomas模型更好的描述G吸附柱吸附TCP模拟废水的动态吸附行为。
[Abstract]:With the rapid progress of modernization, various inventions and technologies have brought great convenience to human life, such as the application of the new type of phosphorus flame retardant. However, the phosphorus containing flame retardant wastewater is discharged into our environment and has been produced to the environment of the earth and its abominable environment. In the process of sewage treatment, the adsorption method has been widely used in environmental treatment in 2004 in the laboratory, because it has a series of characteristics, such as simple operation, high adsorption efficiency, relatively low cost, and not easy to produce two pollution in the environment. After being discovered and developed for the first time, because of the excellent advantages of graphene, it has shown great development prospects in the field of adsorption. As the raw material of this paper, natural scaly graphite powder is selected as the raw material of this paper. The modified Hummers oxidation process is selected and the graphene oxide is prepared by ultrasonic treatment, and hydrazine hydrate is selected as the preparation. Reducing agent, reduction of graphene; using X ray diffraction, Raman spectroscopy, Fourier infrared spectroscopy and BET specific surface area and other physical, chemical characterization of the structure of materials, functional groups and morphology and other characteristics of the study, analysis of the structure and properties of the adsorbents prepared, characterization of adsorbents, and the study of graphene and its Several classical adsorbents were used to simulate the adsorption behavior of phosphorus containing flame retardants and to simulate the static adsorption behavior and fit the dynamic adsorption behavior. The conclusions were as follows: (1) comparison of graphene oxide (GO), single wall carbon nanotube (SWCNT), activated carbon (AC) and graphene (G) simulated waste three butyl phosphate (TBP) waste. The static adsorption performance of water shows that the adsorption performance of G is better. With the increase of reaction contact time, reaction temperature, pH and TBP initial concentration, the adsorption capacity of G to TBP is gradually increased. The adsorption process of adsorbant adsorbent on TBP flame retardant wastewater is simulated by quasi first order, quasi two stage adsorption kinetic model and particle diffusion model. The fitting results show that the adsorption process of TBP is more consistent with the quasi two stage kinetic model, and adsorption belongs to chemical adsorption. Langmuir and Freundlich thermodynamic models are used to fit and analyze the adsorption process of adsorbents for TBP. It is found that the Langmuir model can more accurately fit the thermodynamics process of graphene adsorbed TBP, in the flame retardant agent. There are great potential applications in wastewater treatment. (2) compare the static adsorption properties of graphene oxide (GO) and graphene (G) to the simulated wastewater of trimetholate phosphate (TCP). The results show that the adsorption effect of G on TCP simulated wastewater is obviously better than that of GO. with the reaction contact time, the initial concentration of TCP, the increase of temperature, and the adsorption capacity of adsorbents gradually. In addition, humic acid has a significant effect on the adsorption of TCP by G, while the existence of metal ions in the wastewater has little effect on the adsorption. The model fitting results show that the behavior of G adsorbed on TCP is more consistent with the quasi two order kinetic model, and the thermodynamic model of Langmuir can more accurately fit the thermodynamics process of G adsorption of TCP simulated wastewater. The thermodynamic parameters of the experimental data show that the adsorption is a endothermic process and the adsorption reaction can be carried out spontaneously. (3) the dynamic adsorption properties of graphene to TCP simulated wastewater are investigated. By the control variable method, the adsorption conditions of Shi Moxi column column height, TCP simulated wastewater initial concentration, TCP wastewater flow velocity and so on are compared. The effect of change on the dynamic adsorption properties of TCP adsorbed by G shows that as the influent flow velocity of the TCP simulated waste liquid increases, the penetration of G adsorption column bed layer will obviously accelerate, and the penetration time will come in advance. With the increase of the initial concentration of TCP simulated wastewater, the penetration time of dynamic adsorption gradually decreases, and the penetration curve is clearer. When the height of the G adsorption column changes, the penetration time and the saturation time of G for the dynamic adsorption behavior of TCP simulated wastewater have been changed. When the column height of the adsorption column is increased from 1cm to 2cm and 3cm, the penetration of G to the dynamic adsorption behavior of TCP simulated wastewater begins from 30min, 50min and 100min, and the adsorption saturation time points respectively Two dynamic adsorption models of Thomas and Yoon-Nelson were used for 230min, 290min and 330min. to fit the dynamic adsorption behavior of G adsorbed TCP simulated wastewater. The results showed that the Thomas model better described the adsorption behavior of TCP simulated wastewater by G adsorption column compared to the Yoon-Nelson dynamic model.
【学位授予单位】：江苏大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X703

【参考文献】