Friday, October 20, 2006
Ground Foyer ( Houston Westchase Marriott Hotel)
319

The role of catalytic agents in the thermal transformation of disordered carbonaceous materials

Danielle M. Buckley1, Danny R. Wilks1, Candace M. Coyle1, and Craig P. Marshall2. (1) University of Texas at San Antonio, San Antonio, TX, (2) University of Sydney, Sydney, Australia

Carbon nanotubes (CNTs) are fast becoming an integral part of industry and research due to their implicit applications towards nano-medicine and micro-machines. However, mass production of CNTs is a growing concern owing to the high cost of fabrication. It is well known that the role of iron in industrial processes lowers the activation energy required to induce graphitization. Therefore, we seek to determine if any catalytic affects occur in geological environments using geo-organic matter, specifically ore deposits. Insoluble carbonaceous material (CM) has been isolated from the 1640 Million-year-old HYC McArthur River ore deposit in Northern Territory, Australia, by acid digestion (HF/HCl). A series of thermal experiments using a furnace under inert conditions has been used to study the thermal transformation of CM in response to the catalytic role of sulfur and iron. Sub-samples of CM isolated from within the 2-orebody and host sediment have undergone desulfurization using nitric acid treatment with subsequent 24 hr anaerobic thermal treatment at 300°, 600°, 900°, 1200°, and 1500°C. This heating process will induce either carbonization or graphitization processes depending upon the graphitization ability of the CM. By examining the physical properties of the CM using Raman spectroscopy and ultra-structural techniques such as TEM, we can elucidate the role of catalytic elements such as iron and sulfur in inducing various structural ordering processes in response to the thermal alteration/transformation of geo-organic material.