煤沥青基球状活性炭的结构调控及可控制备

Pitch based activated spherical carbon materials (carbon beads) have vital advanced applications in both national defence and high-tech domestic industries due to their unique performance, which cannot possibly be achieved by common activated carbons. However, the properties of the pitch based activated carbon beads are highly controlled by the chemical and physical properties of the pitch feedstock. In this project, experimental study and numerical modelling and simulation will be employed to investigate the vital relationship between the physicochemical characteristics of the pitch and the pore structure and morphology of activated spherical carbons, Using our novel one-step direct sphericalisation technology as described in this project, this critically important relationship, once established, will effectively enable the production of the target spherical carbons with desirable properties by better informed formulation of precursor pitch feedstocks to yield highly compatible pitch/naphthalene melt. Moreover, the influence of promoter additives on the physical and chemical properties of pitch and its reactivity with oxygen will also be investigated to reveal the mechanism governing the melt-resistant behavior of raw beads during the oxidation stage of the preparation of activated spherical carbons. The melt-resistance of raw beads is critical in obtaining homogenized oxidised spheres for high quality spherical carbon materials. The aim of this project is to establish the relationship between the microscopic structure of raw materials and properties of carbon bead products, which will contribute to the design prediction and control of the properties of spherical carbons and help bridge the underlying technical and fundamental knowledge gaps in the conversion of coal pitch to novel highly value-added spherical carbons. The success of this project will help greatly toward the successful development and commercialization of this novel coal pitch conversion technology.

沥青基球状活性炭由于其独特的性能在国防军工和民用高科技领域具有常规活性炭所不可替代的作用，其性能显著受制于前躯体沥青的组成结构。为此，本项目拟以沥青的组成结构为主要研究对象，借助数学模拟等科学研究方法，重点研究沥青的组成和结构与球状活性炭孔结构之间的相关性，以设计前躯体的组成来调控制备期望性能的活性炭；在研究沥青组分与萘的相容性基础上，通过组分调配获得与萘相容性较佳的沥青/萘固溶体，采用本项目创新性的直接成球技术获得球形度良好的固溶体小球；研究促进剂存在下，沥青的组成结构与氧气的反应活性，揭示氧化不融化的机理，以获得均质化的沥青氧化球；本项目旨在从微观上研究原料结构与产物性能的关系，达到设计、预测、控制产品性能的目的，解决煤沥青转变为高性能的球状活性炭过程中的关键科学问题。项目的成功实施对实现煤沥青至高附加值球状活性炭的转化利用技术的成功开发和产业化应用具有显著的学术价值和现实意义。

沥青基球状活性炭由于其独特的性能在国防军工和民用高科技领域具有常规活性炭所不可替代的作用，其性能显著受制于前躯体沥青的组成结构以及关键的氧化不融化过程的调控。为此，亟需突破煤沥青制备球状活性炭技术及其相关基础理论研究。.围绕沥青基活性炭的可控制备，本项目通过调配沥青中轻、重组分比例，构建了高相容性的沥青-萘-分散剂体系，实现了沥青-萘-分散剂体系的直接成球；基于沥青氧化不融化过程中键的断裂与生成的认知难题，分别从微观、介观、宏观层面针对沥青小球的氧化不融化过程进行了三维数理建模与数学试验优化，通过追踪煤沥青分子氧化过程聚合及裂解反应，获得了不同组分及主要产物的迁移过程以及煤沥青氧化过程反应路径；并结合不同反应器构型，考察了操作条件、颗粒物性参数等对于氧化增重阶段的流动、传热与反应特性的影响，为深入理解氧化不融化过程以及优化工艺奠定了理论基础；在前述模拟基础上，以不同族组分为对象，研究了各族组成的氧化反应活性，发现尽管各族组成的氧化反应活性差异较大，但自由基才是影响氧化不融化的关键，为此分别采用氯仿和联枯为自由基发生剂进行氧化不融化研究，结果表明，C-Cl键以及C-C键分解产生的自由基能够诱导沥青小球的内部和外部均匀氧化，从而解决了在氧化不融化过程缓慢问题的同时，实现了球形活性炭结构的均质化，该成果已在山西省获得应用；依据前述研究，结合沥青组成、结构的特点，研究了在成碳热加工过程中组成结构的演变规律，发现了甲苯不溶物是活性炭中2-4nm孔结构的主要来源，而喹啉不溶物则决定了所得活性炭的形貌，由此定向设计合成了多种孔结构及形貌可控的高性能活性炭。.本项目从微观上阐述了原料结构与产物性能的关系，达到了设计、预测、控制产品性能的目的，解决了煤沥青转变为高性能的球状活性炭过程尤其是氧化不融化过程中的一些关键科学问题，对实现煤沥青资源化利用和洁净转化具有显著的学术意义和实际应用价值。