Production Of Hydrogen And Nanocarbon Via Methane Catalytic Cracking

With our growing population,energy demand is at its highest level,while the reserves of traditional fossil fuel are limited.Continuing to power the world from fossil fuels threatens our energy supply and puts great strain on the environment.A promising altermative to replace fossil fuels and reduce the impact on the environment is hydrogen.Hydrogen production by thermal catalytic decomposition of methane,is the breaking of methane molecules into its primary constituents of hydrogen and carbon in the presence of heat and suitable catalyst.It is a technology that offers high purity hydrogen with zero COx emissions and has the protential to be the major source of hydrogen for hydrogen-powered fuel cell equipment.The by-products named Nanocarbon are also widely used.The aim of this project is to maximise the conversion efficiency of the decomposition of methane into hydrogen whilst also producing quality carbon with high selectively.To achieve the project goals the new methane cracking facility and new catalyst was used to investigate the effects of pressure and carbon dioxide on the decomposition of methane,and also determine the optimum temperature for reduction of the catalyst.The new catalyst was made up by active ingredient include Nickel nitrate,Cobalt nitrate,Magnesium nitrate and Lanthanum nitrate,and catalyst carrier of 316 stainless steel mesh.The gas chromatograph(GC)is the critical component of determine the methane conversion efficiency.Characterisation of the carbon and catalyst was performed using numerous microscopy techniques(SEM/TEM etc.)which provided a feedback loop in the finding of links between the investigated variables and carbon produced.The new eatalyst is eomposed of four active ingredient as Nickel,Cobalt,Magnesium and Lanthanum loaded on the 316 stainless steel mesh.Results from the GC showed that the improved catalyst resulted in a maximum methane conversion efficiency of 83%which can be maintained for almost 14 hours or more.When C02 was in the methane feed stream,the maximum conversion efficiency of methane catalytic cracking was 48%with an average conversion efficiency of 21.8%.The maximum conversion efficiency of pure methane crack was 68%with an average conversion efficiency of 23.7%.The presence of carbon dioxide resulted in formation of larger graphite.So the conclusion is that we can used the mixture gas directly when CO2 was in the methane feed stream.The cost can be reduced in industrial production.Reaction under pressure of 1 bar achieved the highest methane conversion efficiency of 87.4%,whilst under pressure of 7bar managed a maximum conversion efficiency of 56.4%and under pressure of 10 bar only managed to peak at 51.1%.The average of the methane conversion efficiency at the pressure of lbar is 58.0%,while at the pressure of 7 bar is 45.8%and 10 bar is 17.9%.Carbon produced in the reaction under the pressure of 1 bar was highly globular.Whereas,under the pres'sure of 7 bar,besides the globular carbon,there were carbon fibers in the preducts,under the pressure of 10 bar,products were mainly carbon fibers.So we can control the type of nanocarbon by adjusting condition of pressure.It' s the combination of these characteristic traits that allow this project to hold a promising result of best ratio between conversion efficiency and quality of carbon nanotubes.The optimum catalyst reduction temperature was re-tested and the optimum range was 450??50?,not 900? we used before.