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Two types of supports, carbon-modified alumina and alumina−carbon, were prepared in this investigation. These supports were used to prepare hydrotreating (HDT) catalysts for Maya heavy crude. It was found that, when carbon was added to the alumina matrix and the carbon was then burned, pores having larger diameter were generated. The average pore diameter of the support increased with increasing amount of carbon in the alumina. However, when the carbon was not burned, the pore size decreased with added carbon. The hydrotreating activity results show that, because of the larger pore diameter and higher pore volume, the modified-alumina-supported PCoMo catalysts have slightly higher activities than the alumina−carbon-supported catalysts. The effects of additives, boron and phosphorus, on the hydrotreating of heavy oil were also compared. It was found that P-containing catalysts have higher activities than B-containing catalysts. It was also found that, when boron-containing catalyst were prepared at higher pH, they had higher hydrodemetalation (HDM) activities. Deactivation studies showed that the presence of carbon in the support might hinder rate of deactivation during hydrotreating of heavy oil.

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Organic and metalorganic dyes have been incorporated into SiO2 coatings using the sol-gel method. It is found that the coatings prepared from sol-gel starting solutions, which were subjected to a ball milling process, have improved light stability. Using optical absorption, atomic force microscopy and microluminescence measurements, it is found that the ball milling process of the starting solutions not only produces better dye dispersion, but there are also some indications that it produces a structure with fewer and smaller pores. These results are in agreement with previous studies, which indicate that the photostability of dyes in metal oxide matrices can be improved when the dye is better dispersed and trapped in more rigid cages.