Calcination Effects on Texture and Porosimetric Properties of Regular and Nano-Structured Alumina Utilized as Catalyst Support for the FT Synthesis

Samples of regular gamma and nano-structured alumina were prepared and their porosimetric properties evaluated by N-2 porosimetry method. Moreover, cobalt based catalysts for Fischer-Tropsch (FT) Synthesis were prepared by loading cobalt under two calcinations using these alumina supports. Then the porosimetric properties of these materials as well as; their reactor behaviors assessed. Although the nano-structured favored the gamma alumina from pore volume and surface points of view, comparison of porosimetric properties of fresh alumina samples with corresponding catalysts prepared revealed that calcination effect in decreasing those factors was more pronounced for the nano-structured compared to gamma alumina. Also adsorption/desorption isotherms revealed that both materials were mesoporous. Catalytic activity assessment of both catalysts made by these supports showed that nano-structured alumina was more appropriate from activity and liquid hydrocarbon production points of view.