Carbon-Modified Alumina and Alumina−Carbon-Supported Hydrotreating Catalysts

Abstract

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.

Hydrocracking of the crude oil from thermal pyrolysis of municipal wastes over bi-functional Mo–Ni catalyst

“…Though Cata-SP has a larger surface area, its smaller pores have a negative influence on the diffusion and utility of active sites, especially for large molecules. Similar result has been reported for supported Co-Mo catalysts in hydrotreating reaction [39,40]. Thus we can conclude that large-pore Al 2 O 3 is more suitable as support for hydrocracking catalyst.…”

Recent Developments in Environmental Photocatalytic Degradation of Organic Pollutants: The Case of Titanium Dioxide Nanoparticles—A Review

“…The most common approach to the synthesis of CCA supports is based on the "pyrolyzability" of organic compounds, such as cyclohexene, acetylene, or ethane, on the surface of alumina at elevated temperatures (600 ∘ C to 700 ∘ C) in the flow of nitrogen, that is, chemical vapour deposition (CVD) of organic compounds [247,249,254,[258][259][260]. However, it has been found that the materials synthesised by this method have some drawbacks.…”

Facile synthesis of mesoporous Si-containing γ-Al2O3 nanofiber with enhanced thermal stability

“…For example, mesoporous γ-Al 2 O 3 can be used as catalyst or catalytic support due to its high surface area, porosity and surface acidity [6][7][8][9] . High thermal stability is also required for the combustion of catalysts, especially the automotive three way catalysts(TWCs) or diesel oxidation catalysts(DOCs), to maintain a high surface area for the dispersion of active precious metal catalytic components and specific crystalline phase [10,11] .…”