生物质组分快速热解联产生物质炭和碳纳米管的研究OA北大核心

Cellulose,xylan and alkali lignin were used as raw materials to produce an upper carbon layer with nickel foam catalyst from the pyrolyzed volatile components and residual solid carbon(i.e.,lower residual carbon)via rapid pyrolysis.The upper carbon layer obtained from cellulose and xylan contained a large number of carbon nanotubes(CNTs)and was partially doped with graphite flakes,whereas alkali lignin was difficult to form CNTs.The cellulose CNTs contained more graphitized carbon than xylan CNTs,and the degree of graphitization,specific surface area and yield of cellulose CNTs were higher.Cellulose residual carbon and xylan residual carbon had a dense lumpy struc-ture with a low degree of graphitization.The yield of cellulose residual carbon was higher,thus the overall utilization of cellulose was higher than that of xylan.The results showed that cellulose and xylan had lower thermal stability,and the pyrolysis process could produce a large number of volatile components,and most of them were small molecule,which provided a more sufficient carbon source for the formation of CNTs,while alkali lignin had a high thermal stability and fewer gaseous products of pyrolysis,which was not conducive to the formation of CNTs.