乙炔/空气预混火焰合成碳纳米管的影响因素  

Influence Factors of Carbon Nanotubes Synthesis via Acetylene/Air Premixed Flame

作　　者：张倚[1] 潘剑锋[1] 杨辉[1] 卢青波[1] 唐爱坤[1] 

机构地区：[1]江苏大学能源与动力工程学院,镇江212013

出　　处：《燃烧科学与技术》2015年第2期179-185,共7页Journal of Combustion Science and Technology

基　　金：国家自然科学基金资助项目(51376082;51206066);江苏省自然科学基金资助项目(BK20131253);江苏省高校优势学科建设资助项目

摘　　要：火焰法制备碳纳米管的过程中存在许多影响因素.使用涂覆硝酸镍（Ni NO3）溶液的紫铜片作取样基板,通过改变取样时间及催化剂溶液浓度进行实验研究,对合成出的产物使用扫描电镜及投射电镜进行表征,发现延长取样时间或增加催化剂溶液的浓度会导致管径的增大,降低碳纳米管的质量,最终得到催化剂浓度为0.1,mol/L,取样时间为5,min时,生成的碳纳米管质量较好,且数量较多.利用CFD软件对燃烧区域进行数值模拟,分析了合成区域的流场、温度场及碳浓度分布,流场影响了组分停留时间,温度场和碳的浓度影响了碳纳米管的生长速度和碳原子的供给速度,三者对碳纳米管的质量具有重要影响,在合成温度800-1,100,K的范围内,降低温度及碳原子浓度有利于提高碳纳米管的质量.There are many influence factors in the process of carbon nanotubes synthesis via acetylene/air premixed flame. The copper piece coated with nickel nitrate（Ni NO3）was used as sampling substrate. Experimental study was conducted by changing sampling time and the concentration of the catalyst solution,respectively. The synthesized products were characterized by scanning electron microscopy and transmission electron microscopy. It was found that extending sampling time or increasing the concentration of the catalyst solution would cause the increase of diameter and the lowing of quality. When the concentration of the catalyst is 0.1,mol/L and the sampling time is 5,min,the carbon nanotubes of higher quality and larger quantities can be obtained. The combustion area was numerically calculated by CFD software and flow field,temperature field and carbon concentration distribution were analyzed. Flow field affects the residence time of the component,and temperature and the concentration of carbon affect the growth rate of carbon nanotubes and the supply rate of carbon atoms. The three factors have a significant impact on the quality of carbon nanotubes. Within the range of synthetic temperature of 800~1,100,K,reducing the carbon atom concentration would improve the quality of carbon nanotubes.

关 键 词：预混火焰 碳纳米管 影响因素 数值模拟 

分 类 号：TK16[动力工程及工程热物理—热能工程]