蓖麻基多孔材料的制备、特性及应用研究

发布时间：2018-03-16 13:19

  本文选题：蓖麻根茎　切入点：多孔材料　出处：《昆明理工大学》2017年博士论文　论文类型：学位论文

【摘要】：因日益严峻的能源和环境问题,利用生物质前驱体制备多孔材料已成为热点研究方向。由于蓖麻根茎的组织结构疏松,有利于多孔材料的制备,且该原料具有来源丰富、易得、成本低等优点,为此,本论文以蓖麻根茎为原料进行多孔材料的制备及性能研究。将蓖麻根茎进行微波干燥、粉碎,再经制粒制备出蓖麻根茎基多孔材料,为进一步提高多孔材料的性能,将制备的蓖麻基多孔材料进行改性处理,制备出高比表面积的蓖麻基多孔炭。分别采用扫描电子显微镜、比表面积及孔隙分析仪、X射线衍射分析仪、X射线光电子能谱仪、热分析仪、红外光谱仪和顶空分析仪等对蓖麻基多孔材料的结构特性、孔隙特征和性能进行表征,系统地研究了各制备工艺参数对蓖麻基多孔材料特性的影响,探讨了相关作用机制。蓖麻基多孔炭展现出较好的吸附特性、电极材料特性和复合材料载体特性,为蓖麻基多孔炭的开发与应用奠定理论基础。以蓖麻根茎为原料,采用一步制粒法制备出蓖麻基多孔材料,系统地研究了进风温度、喷雾速率和喷雾压力对多孔材料特性的影响,建立了多孔材料的比表面积和水分含量与进风温度、喷雾速率和喷雾压力的关系,从而可以预测不同条件下制备的蓖麻基多孔材料的比表面积和水份含量。最优条件下制备的多孔材料的比表面积和孔容分别为128.58 m2/g和0.13cm3/g,平均孔径为9.9nm。同时,系统地研究了蓖麻基多孔材料的热处理特性,为热处理参数的确定提供理论依据。将制备的蓖麻基多孔材料经低温预处理及化学-物理改性制备出蓖麻基多孔炭,系统地研究了改性温度、碱炭比和改性时间的影响,建立了与比表面积的关系,从而可以预测不同条件制备的蓖麻基多孔炭的比表面积。最优条件下制备的多孔炭的比表面积和孔容分别达2081.92 m2/g、1.10 cm3/g,与改性前相比,分别提高了 16倍和8倍,探讨相关机理。为进一步开展蓖麻基多孔炭的研究提供一定的指导。制备的蓖麻基多孔炭对烟气中的有害物质CO、氢氰酸(HCN)、亚硝胺(NNK)、氨(NH3)、苯并(a)芘(B(a)P)、苯酚及巴豆醛均具有较好的吸附作用,其中,苯酚降低了 29.64%,巴豆醛降低了 15.14%,HCN降低了 20.35%。多孔炭通过表面的物理吸附增加对气溶胶的吸附,同时表面含有丰富的官能团,进一步增加了对有害物质的吸附效果。蓖麻基多孔炭对苯酚溶液的饱和吸附量在碱炭比为4:1时达到最大,为187.5 mg/g;对苯酚溶液的吸附等温模型进行了模拟,最符合Langmuir单分子层等温吸附模型;研究了多孔炭对苯酚溶液的吸附动力学,符合准二级反应动力学;吸附热力学的研究证明,多孔炭对苯酚溶液的吸附为物理吸附,吸附行为为放热的熵减小过程。多孔炭作为电容器的电极材料具有良好的电容行为和特征。在2mol L-1氢氧化钾电解液中,循环伏安曲线呈现面积较大的矩形形状,没有明显的氧化还原峰出现;充电曲线和放电曲线均接近于直线且呈类等腰三角形的形状,具有良好的双电层电容性。作为锂空气电池的电极材料具有较高的首次放电容量和放电平台,且在0.05 mA cm-2电流密度下,多孔炭空气电极具有最高的首次放电容量,达到 2664 mAhg-1。蓖麻基多孔炭对液体中的Ti02有良好的载体作用,形成多孔炭/TiO2复合多孔材料,可以较好的负载2.5%的Ti02,并对甲醛气体具有较好的去除效果;多孔炭对溶液中香料物有良好的载体作用,形成多孔炭/香料复合多孔材料,可以较好的负载5%的津巴布韦净油和酿香香料,顶空分析表明,多孔炭/香料复合多孔材料与香料的成分构成相同,各化合物所占比例相近。
[Abstract]:Because of the increasingly serious energy and environmental issues, the preparation of porous materials by using biomass precursor has become a hot research direction. The structure was loose castor rhizomes, is conducive to the preparation of porous materials, and the raw material has rich source, easy, low cost, for this, this paper study on Synthesis and properties of castor. As the raw material for porous material. The roots of castor microwave drying, crushing, granulating and prepared based porous materials of castor roots, in order to further improve the performance of porous materials, the preparation of castor based porous materials were prepared by modified castor based porous carbon with high surface area were used. Scanning electron microscopy, surface area and pore size analyzer, X ray diffraction, X ray photoelectron spectroscopy, thermal analysis, infrared spectroscopy and headspace analyzer structure of castor porous materials. Of, characterized the pore characteristics and performance were systematically studied the influences of preparation parameters on the castor based porous material characteristics, discusses the related mechanism. Castor based porous carbon exhibits good adsorption characteristics, carrier characteristics of electrode materials and composite materials, which lays the theoretical foundation for the development and application of castor based porous carbon castor. Rhizome as raw material, using one step granulation prepared porous material of castor base, systematically studied the effects of inlet air temperature, spray rate and spray pressure on the properties of porous materials, a porous material surface and the air temperature area and moisture content, the relationship between spray rate and spray pressure. It can be made of castor based porous materials prepared under different conditions to predict the specific surface area and moisture content. The prepared porous material under the optimal conditions, the specific surface area and pore volume were 128.58 m2/g and 0.13 cm3/g,骞冲潎瀛斿緞涓，

本文编号：1620090