Catalytic Cracking Of Ethanol Collaborative Preparation Of Hydrogen And Carbon Nanotube Modified Graphite Nanocomposite Electrode Materials

With the energy crisis becoming more severe and the carbon nanotubes(CNTs) more widely used,it is urgent to make hydrogen and CNTs production in a large scale day by day,so the researchers should integrate material resources,optimize engineering parameters and obtain the objective of economic and efficient technique storage from a strategic height.To get the aim,our group combines hydrogen production technique and CNTs production technique that are both hot topic effectively.Through decomposition of ethanol being catalyzed, co-production of high quality CNTs and high purity hydrogen is achieved.From a catalytic point,my article investigates that graphite-CNTs composite electrode material and hydrogen are achieved at the same time by catalytic cracking method(or catalytic chemical vapor deposition(CCVD))in Fixed-bed-Gas flow cyclic reactor system at a comparatively lower temperature(400～700℃),where the biomass ethanol serves as carbon source and hydrogen source,graphite supports and metal Co and Ni catalysts.Effects of the supports,flow rate,amount of catalyst and decomposition temperature on catalytic cracking of ethanol are observed.Simultaneously,the component and amount of gas are tested by line detect,like TCD and FID,the solid are characterized by BET,SEM,TEM,XRD and other instruments.In the end,constant current charge-discharge cycle test are made on graphite-CNTs composite electrode material as lithium-ion battery anode material by LAND Battery Test System.Results show that:Catalyst Co/C and Ni/C have an obviously catalytic influence on the process of CNTs and hydrogen production;multi-walled carbon nano-tubes(MWCNTs) with comparatively uniform diameter of tube,100%ethanol conversion and 77%hydrogen yield are gotten when particle size of supports graphite is about 3μm,Catalyst precursor calcined at 300℃,the metal loading of catalyst Ni/C of 10 wt%, flow rate of carrier gas of 40ml·min^-1 and decomposition temperature of 600℃;As battery anode material,the first discharge capacity of this carbon composite material is up to 393.7 mAh/g and discharge efficiency reaches 77%.Moreover,the discharge capacity keeps more than 323.gmAh/g and discharge efficiency 99%steadily after many cycles.Results also reveal that:the optimal condition for preparation of graphite-CNTs composite electrode material via decomposition of ethanol that is catalyzed by Co catalyst is at 500℃.At that time,ethanol conversion is up to 93%and hydrogen yield 84%;the diameter of carbon nanotube is uniform and the degree of graphitization is high;As battery anode material,the first discharge capacity of this carbon composite material is up to 510 mAh/g and discharge efficiency reaches 67.5%. Moreover,the discharge capacity keeps more than 367mAh/g and discharge efficiency 98% steadily after many cycles.In addition,this article speculates the formed process of CNTs reasonably.