煤化工VOCs中苯的静电纺丝纳米纤维吸附研究进展

Research progress on adsorption of benzene within VOCs from coal chemical industry by electrospinning nanofibers

随着煤化工行业的不断发展壮大,与煤焦化和煤气化等核心煤化工过程相伴的污染物排放问题日益突出,其中挥发性有机化合物(VOCs)对我国空气质量造成了一定影响。作为VOCs的代表之一,苯有毒性且易挥发,严重危害人类健康。为清晰了解煤化工VOCs排放控制技术的优化方向和发展现状,为煤化工VOCs中苯的净化提供理论储备,梳理总结了静电纺丝纳米纤维复合材料用于苯吸附净化过程的相关材料和技术。围绕目前处理苯的主要技术方法进行分析,指出其在实际应用中存在的问题。重点介绍了吸附法的优点、作用方式、常用吸附剂类型和特点等,并指出选择合适的吸附剂是VOCs及苯等污染物吸附处理的核心,如何选择、组合以及提高各类型吸附材料的吸附性能并寻求有效的吸附净化技术是需要不断完善的课题。重点介绍了具有多孔结构、可调控、高比表面积特点的纳米纤维及其在气体净化领域的运用。从纳米纤维制备角度阐述了静电纺丝合成纳米纤维复合材料的基本原理、基本过程和研究现状,结果表明:静电纺丝设备简单、加工成本低、可纺原料种类多、过程可控,在制备纳米纤维技术中占据绝对优势。与常规纤维相比,静电纺丝纳米纤维尺寸更小、比表面积更大、孔隙率更高,能够在气固反应过程中提供更大的有效反应面积,为活性组分均匀有序分布提供丰富的骨架结构。结合静电纺丝纳米纤维材料净化VOCs的应用现状,指出了该领域存在静电纺丝聚合物纳米纤维和碳纳米纤维机械强度不足、纺丝液溶剂具有毒性和腐蚀性以及静电纺丝效率较低等问题。最后,明确了静电纺丝纳米纤维在VOCs和苯吸附净化领域的发展方向:深入理解并有效预测与控制纺丝过程、加强纺丝材料的功能化扩展以及发掘静电纺丝的工业化应用潜力等。

With the continuous development of coal chemical industry, the emission of pollutants associated with core coal chemical processes such as coal coking and coal gasification has become increasingly prominent, among which volatile organic compounds(VOCs) have a certain impact on China′s air quality. As one of the representatives of VOCs, benzene is poisonous and volatile, which seriously endangers the human health. In order to clearly understand the optimization direction and development status of VOCs emission control technology and provide theoretical reserves for the purification of benzene in VOCs in coal chemical industry, the relevant materials and technologies of electrospun nanofiber composites used in benzene adsorption and purification process was combed and summarized. Focusing on the main technical methods of treating benzene at present, its characteristics were analyzed, and the problems existing in the practical application of these technologies were pointed out. The advantages, action mode, types and characteristics of common adsorbents were focused on, and it is pointed out that selecting appropriate adsorbents is the core of adsorption treatment of VOCs, benzene and other pollutants. How to select, combine and improve the adsorption performance of various types of adsorbents and seek effective adsorption purification technology is a subject that needs to be continuously studied and improved. The nanofibers with porous structure, adjustable and high specific surface area and their application in the field of gas purification were introduced. From the perspective of nanofiber preparation, the basic principle, basic process and research status of electrospinning synthesis of nanofiber composites were expounded. The results shows that the advantages of electrospinning, such as simple equipment, low spinning processing cost, lots of raw materials accessible and controllable process, occupy an absolute advantage in the preparation of nanofiber technology. Compared with conventional fibers, electrospinning nanofibers have smaller size, larger specific surface area and higher porosity, which can provide a larger effective reaction area in the process of gas-solid reaction, improve the rich skeleton structure for the uniform and orderly distribution of active components. Combined with the application status of electrospinning nanofibers materials in VOCs purification, it is pointed out that there are some problems in this field, such as insufficient mechanical strength of electrospinning polymer nanofibers and carbon nanofibers, toxic and corrosive spinning solution solvents, and low electrospinning efficiency. Finally, the development direction of electrospinning nanofibers in the field of VOCs and benzene adsorption and purification was clarified: in-depth understanding and effective control of spinning process, functional expansion of spinning materials and the potential expansion of electrospinning towards industrial application.