催化裂化油浆组成分布对中间相沥青光学织构的影响

以SLO-LH、SLO-SH和SLO-YN催化裂化油浆为原料,利用热缩聚法制备中间相沥青,系统分析了油浆的烃组成分布、沸点分布以及核磁结构特征,关联了中间相沥青光学织构与原料性质组成关系。结果表明,SLO-SH和SLO-YN油浆中的分子量和组成分布较窄,在给定反应条件(430℃、0.7 MPa)下制备中间相沥青的光学织构指数(OTI)值分别为45和50,中间相织构主要由大面积的域及流域组成,镶嵌结构较少。相对于SLO-SH与SLO-YN,SLO-LH样品的烃组成与沸点分布明显疏散,得到的中间相主要由镶嵌组织与小域构成。结果表明集中分布且芳烃含量高有利于得到高收率与高OTI值的优质中间相沥青,对油浆组分进行分离是制备高品质中间相沥青和针状焦的必要途径。     

中间相沥青的调制及其性能研究

以沥青为原料,采用热缩聚法合成了一系列不同各向异性组分含量的中间相沥青(MP)。以不同各向异性组分含量的中间相沥青为原料,采用KOH活化法制备了中间相沥青基活性炭(MP-AC)。使用透反射偏振光显微镜对中间相沥青的显微结构进行静态观察,考察了不同恒温时间中间相沥青的收率和光学显微形态的变化,使用物理吸附仪对MP-AC的比表面积进行了考察。结果表明:反应温度在410℃,恒温6.5 h时可以得到各向异性组分含量约为100%的优质广域型中间相沥青;MP中各向异性组分含量的不同对MP-AC的比表面积影响不大。     

煤液化残渣精制沥青制备中间相沥青的研究

用高压釜进行热缩聚反应,对煤液化残渣精制沥青在热缩聚过程中生成的中间相沥青进行了研究。通过元素分析、偏光显微镜对热缩聚产物进行了分析,考察了反应温度、停留时间、压力及搅拌等对中间相生成的影响。研究表明,在410~430℃,停留4~6 h条件下可以生成中间相沥青,反应初期提高压力有利于中间相的生成,有搅拌的热缩聚效果好于无搅拌的情况。     

原料及缩聚条件对中间相沥青性质的影响

本研究用刮膜蒸发器对制备中间相沥青的原料（软化点为６０℃的石油沥青）进行了分离，并分别以未分离的沥青及分离出的重质沥青为原料在不同的条件下调制成中间相沥青。探讨了原料分子量分布及缩聚过程中温度、Ｎ２流量、缩聚时间对中间相沥青族组成分布、软化点和可纺性等性质的影响。     

中间相沥青调制—热解

文章采用以萘和三氟化硼与氟化氢为原料制备的齐聚物沥青,研究齐聚物沥青在中温条件下通过热缩聚制备出的低软化点,中间相含量高,纺丝性能良好的中间相沥青,探讨齐聚物沥青调制的时间,热缩聚反应的时间以及热缩聚反应的温度对于中间相沥青的影响。     

浅析缩聚沥青性质的影响因素

将闪蒸油通过热缩聚得到制取中间相沥青的原料——缩聚沥青,通过正交试验、馏程改变试验、共炭化试验研究了影响缩聚沥青性质的因素。     

中间相沥青的制备与表征研究进展

中间相沥青是由石油沥青、煤沥青以及其他芳烃类化合物聚合而成的具有各向异性结构的液晶类物质,是制备炭材料的优良前驱体。中间相沥青的制备原料和合成工艺对中间相沥青的性能有显著影响。为了得到理想的中间相沥青产品,研究者们不断改进制备工艺并开发新的制备方法。中间相沥青的性质表征对制备工艺的进一步完善具有重要意义,同时,对后续炭材料能否制备成功起着监测作用。本文综述了中间相沥青的制备方法及表征方法的研究进展,重点介绍了热缩聚、组分优化、加氢改性等制备方法,以及中间相沥青性能的多种表征方法。最后展望了中间相沥青的发展前景。     

高沸点热敏体系精馏过程的研究进展

在精馏系统中，高沸点、热敏性物系分离存在物料受热温度高且时间长的问题，容易引起热敏性物质变质，一直是高效分离与提纯的难点。本文对高沸点热敏性物质精馏分离理论基础进行归纳，提出操作压力低和停留时间短的工艺要求。基于此，总结了分子蒸馏和真空精馏（包括真空蒸馏、真空分馏、真空间歇精馏）在高沸点热敏性物系分离中的优缺点及应用，发现分子蒸馏的真空度和分离程度较真空精馏高，但分离效率和工业化程度比真空精馏低。最后，文章指出，对于采用精馏分离高沸点热敏性体系仍需在新工艺和新设备等方面进行探索，以提高分离效率和降低分离能耗，便于实现工业规模应用。     

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。     

采用加压-真空两段热缩聚法制备中间相沥青炭纤维的原料

以深度裂解石油渣油为原料，采用两段热缩聚法可制得软化点为268℃，可编性良好的中间相沥青。本文详细考察了温度，时间对中间相沥青软化点，可编性，中间相沥青形态及碳化收率的影响，并初步探讨了两段热缩聚反应的机理。研究结果表明反应温度，时间对中间相沥青的结构和性能影响较大，选择适宜石油渣油，采用加压－真空两段热缩聚法，调整反应条件，可制得可纺性良好的中间相沥青。     

煤沥青基中间相沥青的制备研究

以纯化的煤焦油沥青为原料,考察了热聚合温度和恒温时间对中间相沥青的收率、光学显微形态、软化点和族组成的影响.结果表明:反应温度在420℃,恒温5 h时得到了软化点为312℃的流线体型中间相沥青,其收率为79.1%;热聚合反应在相对较低的温度400℃,反应时间为10 h时形成了软化点为305℃、收率为81.4%的优质广域型可纺性中间相沥青.对该原料煤沥青而言,通过控制热聚合反应温度和恒温时间可以达到制备优质中间相的目的.     

热聚合温度对煤液化沥青制备中间相沥青的影响

为制备优质的中间相沥青,以煤液化沥青为原料,在不同热聚合温度下制备中间相沥青,采用偏光显微镜、红外光谱仪、XRD、热分析等测试仪器对所得中间相沥青进行分析和表征。结果表明,温度对中间相沥青的收率、形貌和结构影响显著。随着温度升高,中间相沥青的收率降至86.2%,H含量降至3.96%,S含量有所下降,残炭率增大;中间相小球体的尺寸增大,逐渐出现融并现象,最终形成广域型中间相;煤液化沥青中的稠环芳烃、芳香烃的含量明显增加,烷烃成分则明显减少;煤液化沥青中的无定型区含量减少,分子的排列与取向性变好。选择低的热缩聚温度(410~420℃),适当延长反应时间有利于反应方向的控制,从而达到制备优质中间相的目的。     

闪蒸油制缩聚沥青结构探析

将闪蒸油通过热缩聚得到制取中间相沥青的原料—缩聚沥青，并采用密度法、红外光谱法等手段对内蒸油及缩聚沥青结构进行了探析。     

反应温度对苯甲醛齐聚物及其中间相沥青性能的影响

以中温煤沥青为原料,通过苯甲醛/对甲苯磺酸交联合成出以次甲基相连接的齐聚物,进一步热解制备了中间相沥青,考察了反应温度对齐聚物及其中间相沥青性能的影响。结果表明,随着反应温度的提高,改性煤沥青的收率、软化点、残炭率和密度都呈现上升的趋势;反应温度适当,易于得到光学各向异性发达、软化点较低的优质中间相沥青。     

Influence of bonding carbon on low carbon Al2O3-C refractory composites

The carbonized behavior of binders (carbores pitch, mesophase pitch, high temperature pitch and phenolic resins) was investigated. Meanwhile, the influence of binders, Ni-catalyst and heat treatment on structure and properties of low carbon Al₂O₃-C materials was researched. Mesophase pitch and high molecular weight resin provided higher carbon yield. The synergistic interaction of pitch and phenolic resin provided the higher carbon yield than that of single component. Ni-catalyst changed structure and morphology of bonded carbon promoting the transition of amorphous carbon to crystalline carbon increasing carbon yield and degree of graphitization. High molecular weight phenolic resins, mesophase or carbores pitch and Ni-catalyst worked together providing low carbon Al₂O₃-C samples of excellent strength performance in a wide temperature range and high resistance of thermal shock. Embedding coke in N₂ could promote the generating of carbon fibers which obviously enhanced thermal shock resistance of low carbon (6% flake graphite) Al₂O₃-C materials after heat treatment.     

Kinetics of petroleum pitch polymerization by gel permeation chromatography

The thermal polymerization kinetics of petroleum pitch molecules with molecular weights (MW) between 400–2000 were studied utilizing gel permeation chromatography (GPC). Two distinctly different reaction mechanisms of the petroleum pitch were observed from the GPC curves during transformation of the pitch to mesophase and semi-coke. When mesophase is forming in the pitch, molecules in the MW range of 400–700 were the most reactive, while molecules with MW greater than 1200 were essentially unreactivc. This lack of reactivity of the larger molecules ensures that the mesophase remains highly fluid during its formation. A change in reaction mechanism occurs after the mesophase has solidified as a result of the thermal polymerization reactions. At this stage, there is an abrupt decrease in the reactivity of molecules with MW less than 1100 and the reactivity of all measured molecules is the same. This significant kinetic change is due to a physical phenomenon in which solid state reactions occur in the infusible (vitrified) polymerized pitch. The significantly reduced reaction rates occurring in petroleum pitch after vitrification are similar to the results observed for other thermosetting materials.     

Flow behavior of mesophase pitch

The objective of this work was to provide a comprehensive rheological and structural study of AR mesophase pitch. The shear viscosity of AR mesophase pitch was found to be qualitatively similar to results from prior investigations of mesophase pitch and followed the typical trend for liquid crystalline fluids. However, a distinct hesitation, or kink, was observed in the shear viscosity curve near the shear thinning to constant viscosity transition. This behavior has been seen previously for some low molecular weight and polymeric liquid crystals and was thought to be due to a transition between tumbling and steady alignment of the uniaxial director. Optical studies of mesophase pitch revealed an orientation change of the poly-domain structure at shear rates where the kink was observed. This orientation change results in a high viscosity to low viscosity transition. This viscosity transition, and not tumbling, is responsible for the kink phenomenon. The optical studies also reaffirmed that shear flow reduces the size of the poly domain structure and elongates the domains along the flow direction. Also under quiescent conditions, the poly-domain size increased with increasing relaxation time.     

低QI含量煤沥青氢化产物的结构性质研究

以低QI净化沥青为原料，采用四氢萘高压加氢制取了氢化沥青，采用IR，NMR和TGA分析对氢化沥青及其原料净化沥青进行了对比研究，结果发现氢化沥青含有大量脂环结构，其独特的热解缩聚行为有利于可溶性中间相沥青的制备。