摘要:
When preparing carbon fibers from mesophase pitches, we usually encounter to the formation of cracks along the fiber axis. The crack formation is the most serious and troublesome problem. A simple process which can effectively prevent the crack formation comprises preparing the carbon fibers from mesophase pitches by melt spinning sufficient only to give a rotatory motion to the molten mesophase pitches just before extrusion substantially around the axis of a spinning nozzle hole. The process employs a usual nozzle plate having a pitch introducing tube and a spinning nozzle hole further containing a plug member having an outer spiral groove such as a drill point or a worm gear which is inserted within the pitch introducing tube.
摘要:
A process for the preparation of a high-softening-point pitch rich in mesopores having a softening point measured by temperature gradient method of 150° C. or higher, a weight loss by heating up to 300° C. of 5 wt. % or less and mesopores of 100 mm3/g or greater, in terms of minute pore volume calculated by the Dollimore-Heal method, and a process for making carbonaceous materials carrying metal thereon are disclosed. The high-softening-point pitch rich in mesopores can easily provide carbonaceous material carrying metal thereon by using no oxidizing agent such as nitric acid, and, therefore, the high-softening-point pitch rich in mesopores is especially suitable for the production of carbonaceous materials carrying metal thereon or highly crystalline graphitized carbonaceous materials in a short heating time. The process for the production of a high-softening-point pitch rich in mesopores comprises forming micro-shaped carbonaceous materials having a size of 100 &mgr;m or less, and contacting the micro-shaped carbonaceous materials with an extracting organic solvent so as to remove 20-90 wt. % of light components from the micro-shaped carbonaceous materials. A carbonaceous material carrying metal thereon can easily be prepared by contacting the high-softening point pitch rich in mesopores with an aqueous solution of an anionic surface active agent, and then contacting the material treated with the surface active agent with an aqueous solution of metal salts.
摘要:
A process for manufacturing fine particles or powder of pitch with a high softening point from a heavy oil raw material which is liquid at an ambient temperature or pitch having a relatively low softening point is disclosed. Fine particles of pitch with a high softening point are useful materials and can be used as carbon materials for various applications. A characteristic feature of the process resides in the utilization of emulsion of the heavy oil raw material. That is, it is disclosed a process for manufacturing fine particles of pitch with a high softening point comprising, a first step of stirring a raw material heavy oil in the presence of a surface-active agent and water by a stirring method which can provide a shearing force to produce an emulsion of fine spherical pitch particles dispersed in water, wherein the raw material heavy oil is a liquid having a viscosity of 1,000 poise or less at the stirring condition; a second step comprising causing the emulsion obtained in the first step to come in contact with an extracting organic solvent to extract and remove light components from the fine spherical particles in the emulsion, thereby obtaining fine particles of pitch with an increased softening point; and a third step comprising separating and recovering fine particles of pitch with an increased softening point.
摘要:
When preparing carbon artefacts from heavy oils of petroleum or coal origin, removal of undesirable components or recovery of desirable components from raw materials or intermediates is usually required so as to improve the quality of the final products. Such removal or recovery operation is conventionally done by filtration. In the past, regeneration of filters clogged with solid carbonaceous materials inevitably formed by the filtration operations is difficult and troublesome procedures. Herein disclosed is a simple and effective process for regenerating filters clogged with solid carboneceous materials, characterized by treating the filter medium in an aqueous solution of hydrogen peroxide with heating and then optionally conducting ultrasonic washing in water or a solvent. By this simple process, clogged filters can be regenerated completely to show the same filtration performance as new filters.
摘要:
Commercially attractive continuous processes for the preparation of mesophase pitches for manufacturing high-performance carbon fibers are disclosed. One feature resides in that conversion of a pitch into a mesophase pitch is conducted continuously by using a unique continuous dispersion-heat-treating apparatus. The other feature resides in that the raw material for hydrogenation treatment which is a pretreatment preceeding to the final heat treatment for the production of a mesophase pitch, is prepared by using a heavy oil or pitch having substantially no BTX-insoluble material as the starting raw material, subjecting the raw material to a simple four-step treatment of (1) a continuous heat treatment in a tubular heater, (2) a distillation operation, (3) a BTX-solvent extraction and (4) a distillation operation; while recycling a soluble component obtained in the step (4) to the heat treatment of step (1) and recovering a BTX-solvent insoluble component formed in step (3) as the material for the hydrogenation treatment. This feature can provide a significant increase in the yield of a mesophase pitch. Furthermore, unexpectedly, the recycle of the soluble component into the heat treatment of step (1) is helpful to improve the characteristics of the ultimate products, i.e., carbon fibers or graphite fibers. Combination of the first and the second features, of course, can provide a better commercial success. In fact, the process of the present invention can provide a carbon fiber having a tensile strength of more than 300 kg/mm.sup.2 and a graphite fiber having a tensile strength of more than 400 kg/mm.sup.2 and a modulus of elasticity of no more than 60 ton/mm.sup.2. Processes with minor modifications to the above are also disclosed.
摘要:
Commercially attractive continuous processes for the preparation of mesophase pitches for manufacturing high-performance carbon fibers are disclosed. One feature resides in that conversion of a pitch into a mesophase pitch is conducted continuously by using a unique continuous dispersion-heat-treating apparatus. The other feature resides in that the raw material for hydrogenation treatment which is a pretreatment preceeding to the final heat treatment for the production of a mesophase pitch, is prepared by using a heavy oil or pitch having substantially no BTX-insoluble material as the starting raw material, subjecting the raw material to a simple four-step treatment of (1) a continuous heat treatment in a tubular heater, (2) a distillation operation, (3) a BTX-solvent extraction and (4) a distillation operation; while recycling a soluble component obtained in the step (4) to the heat treatment of step (1) and recovering a BTX-solvent insoluble component formed in step (3) as the material for the hydrogenation treatment. This feature can provide a significant increase in the yield of a mesophase pitch. Furthermore, unexpectedly, the recycle of the soluble component into the heat treatment of step (1) is helpful to improve the characteristics of the ultimate products, i.e., carbon fibers or graphite fibers. Combination of the first and the second features, of course, can provide a better commercial success. In fact, the process of the present invention can provide a carbon fiber having a tensile strength of more than 300 kg/mm.sup.2 and a graphite fiber having a tensile strength of more than 400 kg/mm.sup.2 and a modulus of elasticity of more than 60 ton/mm.sup.2. Processes with minor modifications to the above are also disclosed.
摘要翻译:公开了用于制备用于制造高性能碳纤维的中间相沥青的商业上有吸引力的连续方法。 一个特征在于,通过使用独特的连续分散热处理装置连续地进行沥青转化为中间相沥青。 另一个特征在于,通过使用基本上不含BTX不溶性材料的重油或沥青作为起始原料,制备作为用于生产中间相沥青的最终热处理之前的预处理的氢化处理原料 材料,对原料进行简单的四步处理(1)在管式加热器中的连续热处理,(2)蒸馏操作,(3)BTX-溶剂萃取和(4)蒸馏操作; 同时将步骤(4)中获得的可溶组分再循环到步骤(1)的热处理中,并回收步骤(3)中形成的BTX-溶剂不溶组分作为氢化处理材料。 该特征可以显着提高中间相沥青的产率。 此外,意想不到的是,将可溶组分再循环到步骤(1)的热处理中有助于改善最终产物即碳纤维或石墨纤维的特性。 结合第一和第二功能,当然可以提供更好的商业成功。 事实上,本发明的方法可以提供拉伸强度大于300kg / mm 2的碳纤维和拉伸强度大于400kg / mm 2的石墨纤维和大于60吨的弹性模量 / mm2。 还公开了对上述的微小修改的处理。
摘要:
A process for the preparation of an excellent mesophase pitch suitable for use as a spinning pitch for the production of high performance carbon fibers is disclosed. The mesophase pitch can satisfy the four remarkable characteristics at the same time, i.e., a softening point of below 320.degree. C. as determined by Mettler method, a mesophase content of above 90% as examined on a polarized microscope, a quinoline insoluble content of less than 20%, and a xylene soluble content of less than 20%. The mesophase pitch is particularly homogeneous and is easily spinnable. The process can be characterized by a preliminary extraction step, a continuous heat treatment step, and an extraction step. In some cases, the preliminary extraction step can be omitted. Graphite fibers having a tensile strength of about 400 Kg/mm.sup.2 and a modulus of elasticity of above 60 ton/mm.sup.2 can be obtained from the mesophase pitch. Further, even carbon fibers prepared at a carbonization temperature of 1000.degree. C. have a tensile strength of about 300 Kg/mm.sup.2.
摘要:
A process for an efficient preparation of a mesophase pitch is disclosed. The process is suitable for the production of high performance carbon fibers, from a coal tar or a petroleum residual oil. More particularly, the present invention relates to a process for the preparation of a homogeneous mesophase pitch which comprises a continuous thermal treatment of a heavy oil or a pitch which does not contain quinoline insoluble fractions, in the presence or absence of an aromatic oil, subsequent distillation of the thermally treated product, recovery of a pitch with extremely low quinoline insoluble contents, hydrogenation of the pitch by continuous thermal treatment in the presence of a hydrogen-donating solvent, distillation and recovery of a hydrogenation pitch, and thermal treatment of the hydrogenated pitch. The mesophase pitch prepared by the process of the present invention is suitable for the production of high performance carbon fibers.
摘要:
Until now, it has not yet been succeeded to prepare high performance carbon fibers having satisfactory strength from heavy oils of coal or petroleum origin. We now succeeded to prepare an excellent intermediate pitch which allows the preparation of high performance carbon fibers having tensile strength of higher than 300 Kg/mm.sup.2 and Young's modulus of 50 ton/mm.sup.2.The intermediate pitch can be obtained by heating a heavy oil of coal or petroleum origin in a tubular heater under a specific conditions, and then flash distilling the heater effluent in a flash distillation column under a specific condition so as to remove lighter fractions and recovering heavy fraction from the column bottom as the intermediate pitch. The process for the preparation of the intermediate pitch is simple and economical and allows continuous production without fluctuation of quality of the intermediate pitch. The intermediate pitch is also suitable for the production of higher density carbon products.
摘要:
The present invention relates to a metallocene compound as a catalyst component for the polymerization of olefins, said compound, is stable to air and moisture so that generates no hydrogen halide by hydrolysis and easily handled, and has a high storage stability and a high catalyst activity. Specifically, the catalyst component for the polymerization of olefins comprises a transition metal composition represented by the general formula [1] and [2]: (Ra Cp)m(R′b Cp)M(—X—Ar—Yc)4−(m+n) [1] R″(Rd Cp) (R′e Cp)M(—X—Ar—Yc)2 [2] wherein M is Ti, Zr or Hf; (Ra Cp),(R′b Cp), (Rd Cp) and (R″e Cp ) each is a radical having the cyclopentadienyl skeleton; R″ is a radical which links (Rd Cp) and (R′e Cp); (—X—Ar—Yc) is a grouping in which the aromatic ring Ar substituted by a specified radical Y bonds to M through an oxygen or sulphur atom X.
摘要翻译:本发明涉及作为烯烃聚合的催化剂组分的茂金属化合物,所述化合物对空气和水分是稳定的,因此通过水解不易产生卤化氢并易于处理,并且具有高储存稳定性和高催化剂活性 。 具体地,用于烯烃聚合的催化剂组分包括由通式[1]和[2]表示的过渡金属组合物:其中M是Ti,Zr或Hf; (R a Cp),(R bb),(R d Cp)和(R“C”)各自为具有环戊二烯基骨架的基团; R“是连接(Rd Cp)和(R'e Cp)的基团; (-X-Ar-Yc)是其中被特定基团Y取代的芳环Ar经由氧或硫原子X与M键合的基团。