Investigation of the Effect of Processing Parameters on the Catalytic Formation of Filamentous Carbon on Carbon Fibre Mats

摘要

Nickel catalyst particles were supported on carbon fibres. The carbon fibre mats were impregnated with a nickel salt (I.e. Nickel nitrate) using the incipient wetness technique, the catalyst salt was then decomposed to nickel oxide under nitrogen at 500°C. The impregnated carbon fibre mats were then densified in synthetic natural gas, ethane or synthetic natural gas/hydrogen at temperatures ranging from 550°C to 800°C. The densification gases used provided a reducing atmosphere which converted the nickel oxide to nickel metal. The percentage mass gain of the carbon fibre mats was used to calculate the percentage mass pick-up per hour of the carbon fibre mats, these rates of deposition ranged from approximately 1% to over 50% under varying densification conditions. The carbon fibre mats and the catalytically deposited carbon was characterised using XRD and TEM. XRD was used to identify the state of the catalyst during the different stages of the densification process and TEM analysis showed that the catalytically deposited carbon could be either filamentous in nature or could form a graphitic shell around the catalyst particles.