【作者】 马恩宝；

【导师】 曹宏；

【作者基本信息】 武汉工程大学 ， 材料学， 2006， 硕士

【摘要】 膨胀石墨（EG）对油类物质吸附比大，吸附速度快，且具有低密度，质轻，无毒和高化学稳定性等特性，在吸油后不会造成环境的二次污染。锐钛矿型氧化钛是一种良好的光催化剂。用纳米氧化钛修饰膨胀石墨为去除水体油污染提供了一个新的途径。本文从膨胀石墨的制备和用纳米氧化钛进行修饰入手，借助正交实验、XRD、SEM、FT-IR等方法，对纳米TiO₂修饰膨胀石墨的合成、吸附及催化等方面进行了研究。对该种材料的制备工艺进行子探讨，为其在解决水体油污染方面的应用打下了一定基础。具体研究内容和结果如下：利用化学氧化法成功制备具有丰富孔结构的膨胀石墨，前期试验表明膨胀石墨的膨化体积是影响其吸油能力的的最主要因素，通过正交设计考察了各因素对膨化体积的影响。结果表明膨化温度对石墨的膨化体积影响最大，膨化体积与膨化温度成正相关关系。水洗可以使插层物质向外扩散，水洗次数增加不利于膨化体积的提高。最佳因素水平组合为：膨化温度为1000℃，H₂SO₄：HNO₃为1：1，浸泡时间80min，水洗次数为3次。以石蜡代替油模拟EG吸油过程和储油状态，采用SEM手段研究了它在膨胀石墨中的存在状态，结果表明，表面的孔和内部的开放孔为油提供了储存空间，膨胀石墨吸油后，互相缠绕勾挂形成新的持油空间是其良好持油能力的重要原因；膨胀石墨内部的闭合孔对其持油能力没有贡献。用溶胶-凝胶法对膨胀石墨表面和内部孔壁进行修饰，得到了纳米锐钛矿型TiO₂修饰的膨胀石墨的复合材料EG／TiO₂，其晶粒度在7-20nm之间。通过正交实验，以对甲基蓝的催化降解性能和对机油的吸附性能作为考查指标，讨论了材料制备过程中各因素的影响，得到最佳工艺参数为：P^*为0.8，修饰次数为1次，焙烧时间为20min，焙烧温度为400℃。通过称重法和FT-IR研究了EG／TiO₂对机油的催化降解性能。实验表明，EG／TiO₂对油有良好的催化降解性能。其原因可能是，修饰在膨胀石墨上的氧化钛成三维立体结构，可以更好地接触氧气，同时膨胀石墨吸附的机油为TiO₂的连续降解提供了可靠的来源。此外，实验证明，紫外光可以穿透膨胀石墨，这为修饰在膨胀石墨孔内譬的氧化钛起催化作用提供了可能。更多还原

【Abstract】 Exfoliated graphite （EG） with, low density, avirulence, good stability andso on shows excellent ability in adsorption of oil. It can not introduce secondpollution in use. Anatase titanium oxide is a kind of materials which is goodat catalysis degradation. So TiO₂-modified EG （EG/TiO₂） is one of newmaterials to solve the oil pollution in water.In this paper, EG and EG/TiO₂ were prepared by sol-gel method,researched with Orthogonal experimental and tested by XRD method, SEM,FT-IR and etc. Synthesis, EG/TiO₂’s adsorption of oil and catalysis abilitywere studied also. Lots of information about EG/TiO₂ was shown, whichsupport possibility of EG/TiO₂’s use in solving oil pollution in water.EG has been prepared in the way of chemcial-oxidization. Prophaseexperiment shows that unit volume has great effect on absorption of oil, so theinfluences of factors on unit volume were studied. It was shown thattemperature plays the most important role, the unit volume of EG keeppositive-going as temperature increase; water wash can make the intercalationescape from graphite layer, and reduce the unit volume. The best level is thattemperature is 1000℃, volume of acid ratio （H₂SO₄:HNO₃） is 1:1, time ofimmersion is 80min and time of washing is 3.With SEM method, wax was used to show process of EG’s absorptionand storage of oil, it was shown that the open pores in and on EG supplystorage room for oil, closed pore is useless in adsorption process, meanwhilewhen EG touch oil, they conjunct and create new storage room, this is thereason for absorption.Through sol-gel method, EG was modified by anatase titanium oxidewith grain size of 7-20nm. Catalysis degradation of methyl blue and thesorption of oil of EG/TiO₂ was studied by orthogonal. We discussed influenceof different factors, and the best association is that P（the ratio of TiO₂） is 0.8,time of coating is 1 and roasting time 20min and temperature 400℃.Weight loss method and FT-IR spectrum was used to characterize theoil’s degradation ability. In experiment, EG/TiO₂ shows good catalysis ability.The probably reason as follow: in EG/TiO₂, titanium oxide can contact moreoxygen for its three-dimension form, EG can provide enough oil for TiO₂ in catalysis process. In addition, the ultraviolet light can penetrate graphite,which promote the degrade process of TiO₂ coated on EG.更多还原