中国炭材料用煤沥青的生产和应用

文章介绍了中国煤沥青资源生产和应用现状，剖析了影响煤沥青市场的几个因素，探讨了改质煤沥青的应用前景以及在炭材料生产中应用时面临的问题，讨论了中国煤沥青质量评价体系，并对炭材料生产用煤沥青的质量指标进行了详细的分析。     

炭材料生产用煤沥青的流变性能

介绍了流体的特性及其表征，描述了煤沥青的流变性能及其在炭材料实际生产中的意义，综述了煤沥青流变性能研究状况。提出了炭材料生产用煤沥青流变性能研究所面临的课题。     

炭材料生产中煤沥青流变性能的调节

煤沥青流变性能对炭材料生产影响极大,煤沥青流变性能的合适调节及相应工艺参数的优选对于提高炭材料质量有着重要的作用。文章讨论了混捏、成型、焙烧和浸渍过程中影响煤沥青流变性能的因素,分析了工艺参数变化对煤沥青流变性能的调节作用,提出了改善煤沥青流变性能的措施。     

高性能炭材料生产用煤沥青的研究

研究了软化点在评价煤沥青聚合程度中的作用；描述了热聚合改质过程中煤沥青热解缩聚行为，分析了中温煤沥青热聚合改质过程中各种沥青组分随热聚合温度和热聚合时间的转变规律，探讨了QI组分影响煤沥青热聚合改质的机理，认为原料煤沥青所含原生QI炭微粒促进了热聚合改质过程中煤沥青芳烃分子的聚合；描述了煤沥青的流变性能及其在炭材料实际生产中的意义，研究了中温沥青和改质沥青高温流变性能的差异，探讨了硬脂酸和油酸对煤沥青的改性作用；分析了煤沥青的热解缩聚特征，研究了升温速率对煤沥青热解缩聚的影响。     

中间相沥青基泡沫炭的研究进展

中间相沥青基泡沫炭是一种具有低密度、高强度、高导热、高导电、耐火、耐高温、抗冲击、抗氧化等性能的新型炭材料,具有广泛的应用前景.不同的原料和方法所制备的沥青基泡沫炭的结构、性能和应用也有所不同,通过对以石油系、萘系和煤沥青或改性煤沥青为原料制备中间相沥青基泡沫炭,讨论了制备工艺对泡沫炭的影响,同时对泡沫炭的改性研究及应用进行了概述.     

炭材料工业生产用黏结剂和浸渍剂煤沥青的再认识

1炭材料生产用煤沥青的不可替代性尽管煤沥青是污染性严重的多环芳烃有机物质,但炭材料生产还是依赖煤沥青作为黏结剂和浸渍剂(美国等也采用特有的石油沥青作为浸渍剂),这是由于煤沥青具有独特的"强黏结能力、富碳低灰、热塑性、固态(类似玻璃态)与液态的可逆转化、与固体炭质物料极好的配伍性和亲和力、较高的结     

净化煤沥青的主要制备工艺、表征方法及应用概述

净化煤沥青具有含碳量高、杂原子及灰分含量低、芳香度高、分子结构中含有烷基短链等特点,是制备高性能炭材料的优质前驱体。另外,由于净化沥青本身具有来源广泛、价格低廉的特点,在炭石墨材料及C/C复合材料领域受到广泛的关注。本文阐述了净化沥青的主要制备工艺、常用表征方法、在人造炭材料领域的应用,展望了净化煤沥青的应用前景。     

初探煤沥青及其应用

煤沥青是煤焦油蒸馏后的残渣,为制取各种新型炭材料不可替代的原料。本文介绍了煤沥青的组成、性质、分类及其在浸渍剂、黏结剂、针状焦、碳纤维、泡沫炭等方面的应用。     

黏结剂用量对炭-石墨材料的影响

在炭-石墨材料制备过程中黏结剂煤沥青用量对材料的各项性能有重要的影响。本文对不同黏结剂煤沥青含量的生坯微观结构,以及炭-石墨材料制备工艺的关键参数进行了研究,为炭-石墨材料的制备提供参考。     

煤直接液化残渣性质及高附加值应用研究进展

介绍了煤直接液化残渣的组成，结构和性质，综述了液化残渣高附加值研究现状。总结前人研究成果，取得成绩及面临问题的基础上，指出了今后研发的焦点——沥青改性剂和炭材料，摒弃液化残渣的传统低效率应用，对于中国的煤直接液化事业具有重要的指导意义。     

Rheological characteristics of coal tar and petroleum pitches with and without additives

An extensive study of rheological characteristics of coal tar and petroleum pitches with and without additives, namely, petroleum coke, natural graphite and carbon black has been made. It is found that all pitches, pure or mixed with a carbon additive are not Newtonian as reported in the literature, but behave Theologically as Bingham plastics with certain yield stress and plastic viscosity at all temperatures of measurement between 85–180°C. The yield stress and plastic viscosity both decrease with increase in temperature of the pitch. A pure petroleum pitch having the same softening point as that of a coal tar pitch is found to have a lower viscosity compared to that of the latter at all temperatures of measurement. This suggests that the criterion of softening point as a measure of suitability of a coal tar pitch binder in the manufacture of artificial carbon is not sufficient for petroleum pitches. Addition of ten parts of carbon black by weight of pitch results in a considerable decrease in viscosity change with temperature of the coal tar pitch compared to almost insignificant change in the case of the petroleum pitch of the same softening point. However, the addition of petroleum coke or natural graphite makes the pitch more viscous but does not change the temperature dependence of viscosity of either of the two types of pitches. The implications are discussed.     

煤沥青基功能碳材料的研究现状及前景

我国煤沥青资源丰富,但深加工技术落后,产品附加值低,实现煤沥青高附加值利用是亟待解决的重大课题。本文介绍了以煤沥青为原料合成高性能功能碳材料的主要技术,重点阐述了以煤沥青为原料制备中间相沥青、多孔碳材料、碳纤维、二维纳米碳材料及碳基复合材料的研究进展。分析表明,高芳香性和高缩合度分子结构所引起的强π-π相互作用是阻碍煤沥青基高性能功能碳材料设计合成的瓶颈问题。通过催化聚合、氧化、共热解等技术手段可有效改善煤沥青分子结构及其物理、化学性质。结合模板复制、物理/化学活化、界面诱导以及催化石墨化等技术可实现多种功能性碳材料结构设计与表面化学性质调控。发展煤沥青分子结构调控新技术作为改善煤沥青基碳材料性能的重要策略,需要系统深入研究。     

沥青球平均粒径与成球原料粘度相关性的研究

选用了3种典型煤沥青为初始原料，通过助剂配合法将其分别调制为精制沥青，再采用介质分散法将其制成普通沥青球(OPS)。考察了不同温度下成球原料的粘度和OPS平均粒径的变化特点，并将二者进行并联。试验发现，经调制的成球原料的粘度对数值与OPS的平均粒径随着温度的变化具有规律性。两参数之间的关系可以用简单线性回归方程表达。     

Wood-Derived Tar as a Carbon Binder Precursor for Carbon and Graphite Technology

In addition to the many benefits of coal tar pitch, these materials are known to contain polycyclic aromatic hydrocarbons. For this reason, studies are being developed to elaborate new, ecologically friendly, alternative binders for carbon–graphite technology. This article presents the results of wood tar recovered during thermal degradation of selected types of woods as alternative binders in the manufacture of carbon materials. Two kinds of wood tars obtained from different raw materials were analyzed. Sawdust thermal conversion makes it possible to obtain carbon binders with a lower coking value and quinoline-insoluble matters in comparison to coal tar pitch. These binders produce significantly reduced emissions of polycyclic aromatic hydrocarbons in carbon–graphite technology. Carbon samples manufactured using wood-derived binders with carbon fillers showed similar density and mechanical compression strength values compared to those based on conventional coal tar pitch binders.     

煤沥青加氢的有效途径

针对煤焦油沥青高芳香度、高缩合度和高杂原子含量的特点,在用作制备高性能沥青基炭纤维及其它高级炭材料的原料时,须对煤沥青进行改性处理。详细介绍了煤沥青加氢还原的有效途径,包括Birch还原法、溶剂加氢法、催化氢化法、醇类加氢法和电化学加氢法等,并对加氢作用机理及其应用前景作了详细评述。     

煤沥青及其改性后中间相的转化行为研究

以煤沥青(CTP)和改性沥青(MCTP)为原料,在氮气保护下,采用热聚合的方法,制备出两种中间相沥青(MPPA和MPPB),采用FTIR与热分析对CTP与MCTP的中间相转化行为进行了研究.通过偏光显微镜分析,MPPA为镶嵌结构,MPPB为流域结构,对两种中间相沥青进行XRD分析,发现MPPB比MPPA具有较好的晶态结构.     

Étude des phénomènes de mouillabilité du carbone par le brai liquide

One of the processes used in the manufacture of carbon/carbon composites makes use of impregnation with pitch of a multidirectional structure of carbon rods made of carbon fibres at high temperature followed by carbonization under high pressure. A densification of the composite is obtained by repeated impregnations.Since the mechanical properties of the composites must likely depend on the quality of the interface formed between the carbon rod and the liquid pitch matrix, the wetting properties of pitches of various origins and properties (Table 1) were studied for several carbon rods (Table 2). A tensiometric method based on the weight of pitch lifted during immersion of the carbon rod at 350°C was used (Fig. 1).Measurements of the surface energy of the pitches in the liquid state at 350°C (Table 3) and in the solid state at room temperature (Table 4) show that the surface energy is practically independent of the origin of the pitch and that the surface polarity of the pitch is negligible. On the contrary, the values of the contact angle at 350°C is higher for the petroleum pitch No. 1 than for the coal tar pitches (Table 5).The wettability criteria, i.e. the spreading coefficient S and the wetting tension τ, derived from the measured surface energy and contact angle, confirm the lower wetting ability of the petroleum pitch (Fig. 2). These criteria may explain why the densification process (number of impregnations and carbonization cycles necessary to reach an apparent density of the composite of 1.90) is much more difficult with petroleum pitch. On the contrary, the adhesion criterion factor, expressed as the reversible energy of adhesion between the liquid and the solid at 350°C, has the same value whatever the origin of the pitch. Since the degree of adhesion might influence the quality of the carbon/carbon interface in the composite, the same value of the adhesion criterion factor may explain why all composites, at equivalent density, show about the same compression and torsion strengths.The difference between the wettability and adhesion for the pitches of different origins is due to the difference in the spreading pressure π; this quantity measures the decrease of the surface energy of the carbon rod resulting from the adsorption of the pitch vapor. The calculations reveal that, whatever the surface energy of the carbon rod, the petroleum pitch leads to a larger reduction of the surface energy of the solid than the coal tar pitches (Fig. 3).The wettability and adhesion criteria adopted in this study seem to (at least to a first approximation) explain the dependence of the mechanical properties of the carbon/carbon composites on the type of pitch and on the processing conditions.     

Modified characteristics of mesophase pitch prepared from coal tar pitch by adding waste polystyrene

The toluene soluble of coal tar pitch was carbonized with waste polystyrene. The properties of mesophase pitches were characterized using polarized light optical microscope, apparent viscometer, FT-IR, ¹H NMR and X-ray diffractometer. After adding the waste polystyrene into the toluene soluble of coal tar pitch, the soluble mesophase were was increased from about 9% to 52% and the mesophase pitches were changed from 74% with coarse mosaic texture to 100% with flow domain texture. The mesophase pitches were transformed from thixotropy to unthixotropy. By waste polystyrene added into the toluene soluble of coal tar pitch, the methylene group was increased a lot. The presence of more alkyl groups modified the characteristics of mesophase pitches and improved the assembly of mesophase pitch molecules.