摘要
以商用乙炔为碳源,镍板为催化剂,含硫化合物为助催化剂,通过气相催化裂解法(VCC)制得了微米级螺旋形炭纤维。通过对影响微螺旋形炭纤维生长因素研究,发现将镍板直立放置于石英管中,可以提高螺旋形炭纤维的收率。同时发现反应温度为710℃～800℃,C2H2 H2=1∶3,含硫化合物的流量为1.0mL min～1.2mL min时,有利于规整螺旋纤维的生成。通过调节N2的流量,可以获得螺径不同的炭纤维。气体总流量约200mL min时可制得螺径约4μm的规整炭纤维;气体总流量约150mL min时可获得螺径约20μm的炭纤维。利用扫描电子显微镜(SEM)考察了螺旋纤维的微观形貌,发现所得的纤维几乎为双螺旋,同时在螺旋纤维生长的先端常观察到由弯曲纳米级纤维形成的绒状物。
Carbon micro-coils were prepared by. a vapor phase catalytic cracking (VCC) process, using commercial acetylene as the carbon source, a nickel plate as catalyst and a sulfur compound as impurity. Reaction conditions which affected the growth of carbon micro-coils were investigated. The nickel plate was located in the center of quartz tube with carbon micro-coils growing on both sides. The carbon yield for the nickel plate is higher than that for nickel powder. The optimum reaction conditions for carbon micro-coil formation were as follows: reaction temperature 710 degreesC 800 degreesC, the ratio of C2H2, to H-2 1: 3, the flow rate of impurity 1.0 mL/min similar to 1.2 mL/min. Carbon micro-coils with different coil diameters were obtained by regulating the N-2 flow rate. Carbon micro-coils with coil diameter about 4 rim and about 20 rim were obtained with total gas flow rates of 150 mL/min and 200 mL/min respectively. The microstructures of the carbon micro-coils were examined by SEM. It was found that most of carbon micro-coils were double helical forms with villiform tips composed of curved nanofibers.
出处
《新型炭材料》
SCIE
EI
CAS
CSCD
2003年第1期31-36,共6页
New Carbon Materials
