Health & Environmental Research Online (HERO)


Print Feedback Export to File
1666709 
Journal Article 
Deposition, gasification and reduction of pyrocarbon on the surface of iron oxide 
Wu Wen-jun; Zhu Yong-ping; Zhang Wei-gang 
2007 
Unk 
Xinxing Tancailiao
ISSN: 1007-8827 
22 
2 
177-182 
WOS:000247702700015 
Thermodynamic analysis and chemical vapor deposition (CVD) of pyrolytic carbon on the surface of needle-like goethite (FeOOH) in a flow reactor were carried out. It was found that CVD of carbon from propylene occurred on the surface below 600 degrees C. With the deposition of pyrocarbon, the surface area of the FeOOH decreased rapidly and mass loss occurred resulting from dehydration. With increasing CVD temperature, Fe2O3 was reduced gradually to Fe3O4 and FeO and finally Fe3C as the CVD temperature exceeded 800 degrees C. Carbon deposited on the surface of iron oxide below 500 degrees C limited the morphological change of nano FeOOH from large aspect ratio particles to spherical particles. At higher temperatures (600-700 degrees C), carbon deposition led to the formation of dumbbell shaped iron oxide. The two forms of iron oxide can be reduced by carbon monoxide or hydrogen into pure iron or carbon coated iron with high aspect ratios or a dumbbell shape. 
chemical vapor deposition; carbon coating; iron oxide; iron