Influence Of Adding FCC Slurry On Properties Of Carbon Fiber Prepared From Coal Pitch

Carbon fiber is widely used in aircraft,automobile,sports leisure products,construction,oil fields and other fields,which is very important to China's national economy and people's livelihood,but its production cost and performance restrict the development of carbon fiber.High temperature coal tar pitch(HCTP)and catalytic cracking slurry(FCC)are important heavy organic carbon resources.They can be used as precursors for the preparation of carbon materials with excellent performance,which has far-reaching significance for the preparation of domestic pitch based carbon fibers with low cost and excellent performance.The two raw materials were pretreated to RHCTP and RFCC.In this paper,the spinning asphalt was prepared by adding RFCC of different quality into RHCTP,and then carbon fibers were obtained by spinning,oxidation and carbonization.RHCTP,RFCC,spinnable pitch,precursor fiber,oxidized fiber and carbonized fiber were characterized in order to investigate the effect of RFCC on the preparation of carbon fiber.The characterization methods were CPP-GC/MS,XPS,Raman,SEM,FTIR and TG/DTG.The characterization of RHCTP and RFCC shows that the C content of RHCTP and RFCC increases.C is mainly aliphatic carbon/aromatic carbon,O is mainly C-O,N contains more pyrrole nitrogen,and S contains more aromatic sulfur.RHCTP is mainly aromatic compounds,the molecular weight of which is between 200-400.RFCC contains a lot of aromatic and alkane components,and the molecular weight of which is between 250-400.The characterization of different spinnable asphalts showed that the content of C increased,while the content of N,S and O decreased compared with RHCTP.RFCC can produce certain hydrogen radicals during polymerization pyrolysis,which can slow down the formation rate of aromatic macromolecules and improve the rheological properties of spinnable asphalt.With the addition of RFCC,more aromatic ring macromolecules were obtained,the order of carbon layer was strengthened,the content of carboxyl oxygen and pyrrole nitrogen increased,and the content of intermediate phase increased.The results show that with the addition of RFCC,the phenomenon of broken yarn is improved,the longest spinning length is increasing and the diameter of the fiber increases.When RFCC is 20%,the broken and wool of the fiber is very rare,and the surface of the original fiber is fine and smooth without obvious defects.The characterization of different oxidized fibers shows that with the addition of RFCC,the content of H,C and H/C increase,while the content of O decreases.The infrared absorption peaks are mainly O-containing functional groups and aromatic functional groups.The carbon layer of the pre-oxidized fiber O-C obtained with RFCC accounting for 20% has a higher degree of order,and more benzene rings and fused ring macromolecules are generated.Characterization of carbon fiber shows that carbon fiber has fewer infrared absorption peaks and forms a fused ring compound with a larger molecular weight.The thickness of the four types of carbon fibers is more uniform and there are fewer attachments.With the addition of RFCC,the axial splitting phenomenon of the obtained carbon fiber slows down,and the overall tensile strength and modulus are increasing.The tensile strength of C-C is 708 MPa and the tensile modulus of C-C is 49.5GPa.The average diameter of the four carbon fibers is within14-17?m,which meets the general-purpose pitch-based carbon fiber standards.This paper has 44 pictures,27 tables and 106 references.