论文总字数：21645字

摘 要

有机染料的出现，极大丰富了人们对多彩生活的需求，染料的合成与应用已广泛渗透到人们的日常生活中。随着人们对染料需求的日益增加，染料行业产量激增，但与此同时，大量有机染料废水的排放对生态环境以及经济可持续发展造成了不小挑战。为了迎合绿色化工生产的理念，需对染料废水进行后处理。通过分子吸附、再生对染料进行吸脱附，可以很好的解决上述污染问题。石墨烯，作为新型碳纳米材料，因其较大的比表面积，有利于染料的吸附，同时由于碳材料质轻且无污染，有着广阔的应用前景。

本文通过改进Hummer’s法制备氧化石墨烯，通过热剥离技术制备石墨烯粉体。采用扫描电子显微镜、X射线衍射、氮气吸脱附测试对热剥离前后粉体的形貌、结构、比表面积进行了比较。发现短时间1min的热剥离能够将石墨烯粉体的比表面积提升14.5倍，至240.4 m²/g。然后，以阳离子染料亚甲基蓝（MB)为目标分子，研究了石墨烯粉体对染料的吸附性能。通过紫外光谱测定吸附前后染料的吸光度，发现溶液体积量越少、石墨烯粉体量越少，越有利于石墨烯对MB平衡吸附量的提升。根据Langmuir吸附模型，通过不同浓度体系的研究，拟合得到石墨烯对MB的最大吸附量为283.4 mg/g。同时，通过调控溶液pH，发现碱性条件下石墨烯对MB的平衡吸附量提升明显，在pH为12时平衡吸附量可达414.8 mg/g。

关键词：石墨烯 热剥离 亚甲基蓝 吸附

Study on Preparation and Adsorption Properties of Graphene

Abstract

The emergence of organic dyes has greatly enriched people's needs for colorful life. Till now, the synthesis and application of dyes have been widely used in people's daily lives. With the increasing demand for dyes, the output of the dye industry has surged. However, at the same time, the discharge of large amounts of organic dye wastewater has also caused much challenges to the environment and sustainable economic development. In order to cater to the concept of green chemical production, post-treatment of dye wastewater is required. The adsorption and desorption of the dye through molecular adsorption and regeneration can solve the above pollution problem. Graphene, as a new type of carbon nanomaterial, possesses large specific surface area, which is conducive to the adsorption of dyes. In addition, the carbon material has broad application prospects due to its light weight and no pollution.

In this paper, graphene oxide is prepared by improved Hummer ’s method, and graphene powder is obtained by thermal exfoliation technology. The morphology, structure and specific surface area of the powder before and after thermal exfoliation were compared by scanning electron microscope (SEM), X-ray diffraction (XRD) and nitrogen adsorption desorption test (BET). It was found that a short time (1 min) thermal exfoliation process can increase the specific surface area of powder by 14.5 times to 240.4 m²/g. Then, the cationic dye methylene blue (MB) was used as the target molecule, and the adsorption properties of graphene powder were studied. The absorbance of the dyes before and after adsorption of graphene was measured by ultraviolet spectroscopy (UV). It was found that the smaller volume of the solution and the smaller amount of graphene powder, the more favorable the improvement of the equilibrium adsorption of MB by graphene. According to the Langmuir adsorption model, through the study of different concentration systems, the maximum adsorption capacity of graphene to MB was 283.4 mg/g. In addition, by adjusting the pH of the solution, it was found that the equilibrium adsorption capacity of graphene to MB increased significantly under alkaline conditions, and the equilibrium adsorption capacity could reach 414.8 mg/g at pH 12.

Key words: Graphene; Thermal exfoliation; Methylene blue; Adsorption

目 录

摘 要 I

Abstract II

目 录 IV

第一章 绪论 1

1.1石墨烯 1

1.1.1石墨烯概述 1

1.1.2石墨烯结构 1

1.1.3石墨烯性质 1

1.1.4石墨烯制备 3

1.1.5石墨烯应用 4

1.2石墨烯吸附 5

1.2.1石墨烯的吸附机理 5

1.2.2石墨烯吸附处理印染废水研究进展 5

1.3课题意义和研究目的 6

第二章 实验部分 7

2.1试剂和仪器 7

2.1.1实验药品 7

2.1.2仪器设备 7

2.2表征方法 7

2.2.1 X射线衍射（XRD） 8

2.2.2 扫描电子显微镜（SEM） 8

2.2.2 比表面面积测试（BET） 8

2.2.2 紫外光谱测试（UV） 8

2.3实验过程 8

2.3.1氧化石墨的制备 8

2.3.2 氧化石墨烯粉体的热剥离 9

2.3.3石墨烯对MB的吸附测试 9

第三章 氧化石墨烯的热剥离及吸附性能测试 11

3.1氧化石墨烯的热剥离 11

3.1.1 XRD表征分析 11

3.1.2 SEM表征分析 11

3.1.3 BET表征分析 12

3.2石墨烯的吸附性能测试 13

3.2.1 MB标准曲线的绘制 13

3.2.2 MB吸附平衡时间的确定 14

3.2.3体积量对MB吸附性能的影响 15

3.2.4石墨烯粉体量对MB吸附性能的影响 15

3.2.5最大MB吸附量的确定 16

3.2.6 pH值对MB吸附性能的影响 17

第四章 结论与展望 19

4.1结论 19

4.2展望 19

参考文献 21

致谢 23

第一章 绪论

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