采用共沉淀法制备了铁基水滑石催化剂,通过X射线衍射(XRD)、扫描电子显微镜(SEM)、红外光谱(FT-IR)、透射电子显微镜(TEM)等对催化剂进行表征;研究了催化剂焙烧温度对其理化性质和催化丙烯裂解制备碳纳米管的影响。结果表明,当焙烧温度为500℃时,催化剂的比表面积和催化倍率达到最大,分别为130.71 m²/g和1 800%;碳纳米管的缺陷程度最小,仅为0.98,此时碳纳米管的直径分布也较为均匀,集中在10~14 nm范围内。合理的焙烧温度有利于活性物质在载体表面分散,能使催化剂具有较高的比表面积、孔体积,因而能够制备出产量高、直径均匀、石墨化程度高、灰分少、电阻率低的碳纳米管。

Iron-based hydrotalcite catalysts are prepared through co-precipitation method,and characterized by means of X-ray diffraction (XRD),scanning electron microscopy (SEM),infrared spectroscopy (FT-IR),transmission electron microscopy (TEM),etc.The effects of catalyst calcination temperature on their physicochemical properties and the catalytic preparation of carbon nanotubes by propylene cracking are investigated.The results indicate that the specific surface area and catalytic multiplying power of the catalyst reaches the maximum ones,130.71 m²·g^-1 and 1 800%,respectively when the calcination temperature is 500℃.The defect degree of carbon nanotubes prepared over the catalyst is the smallest,only 0.98,and the diameter of carbon nanotubes also distributes more uniformly in the range of 10-14 nm.The reasonable calcination temperature is beneficial to the dispersion of active substances on the support surface,which can make catalysts have higher specific surface area and pore volume,and thus prepare carbon nanotubes with high yield,uniform diameter,high graphitization,low ash content and low resistivity.

闫超(1998-),男,硕士研究生,研究方向为碳纳米管及催化剂的合成与制备,2593900039@qq.com。