Hydrocracking catalysts for vacuum gas oil & de-metalized oil blend

Abstract

This invention relates to a catalyst and a process for treating heavy hydrocarbons using the catalyst. The catalyst is useful for treating heavy hydrocarbons, de-metallize oil (DMO) and is particularly useful in VGO / DMO hydrocarbon blend. It is also useful for DAO. The catalyst acts to catalytically convert the VGO / DMO blend to shorter-chain valuable hydrocarbon products. The catalyst includes a catalytic support material, a catalytic metal impregnated upon the catalytic support material, and a promoter metal on the catalytic support material to enhance catalytic conversion. The combination of the catalytic support material with catalytic metal and promoter metal is operable to catalytically convert VGO / DMO into hydrocarbon products having shorter carbon chains.

Description

RELATED APPLICATIONS [0001] This patent application claims priority to U.S. Provisional Patent Application Ser. No. 60 / 639,909 filed on Dec. 29, 2004, which is incorporated by reference in its entirety.BACKGROUND OF THE INVENTION [0002] 1. Technical Field of the Invention [0003] This invention relates generally to the field of catalytic treatment of heavy hydrocarbons to produce desirable hydrocarbon products, in particular, a novel catalyst operable to catalytically treat de-metallized oil (DMO) and Vacuum Gas Oil (VGO) Blend. [0004] 2. Description of the Prior Art [0005] The flexibility of hydrocracking as a process for refining petroleum has resulted in its phenomenal growth during the past 15 years. Through catalytic treatment, feedstocks can be converted to lower boiling or more desirable products. Hydrocarbon feedstocks suitable for such treatment range from residue to naphtha. Products include such widely diverse materials such as gasoline, kerosene, middle distillates, lubri...

AI Technical Summary

Benefits of technology

[0008] The current invention includes a catalyst for and a process for hydrotreating / hydrocracking heavy hydrocarbons. The catalyst is particularly useful for treating de-metallized oil (DMO) and is particularly useful in VGO / DMO hydrocarbon blend. The catalyst acts to catalytically convert the VGO / DMO blend to shorter-chain valuable hydrocarbon products. The catalyst includes a catalytic support material, a catalytic metal impregnated upon the catalytic support material, and a promoter metal on the catalytic support material to enhance catalytic conversion. The combination of the catalytic support material with catalytic metal and promoter metal is operable to catalytically convert VGO / DMO into hydrocarbon products having shorter carbon chains.

[0011] In another preferred embodiment, the catalytic support material is β-zeolite. In another preferred embodiment, the catalytic support material is USY zeolite. In yet another preferred embodiment, the catalytic support material is amorphous silica alumina, also called ASA. ASA has a non-uniform structure with low acidity and high surface area. The non-uniform structure tends to create acidic sites that are not available to large molecules, which leads to inferior performance of ASA alone as compared to MCM-41 or a combination of MCM-41 with ASA. Similarly, the USY and β-zeolite supports suffer from drawbacks related to the microporous nature of the supports which makes the catalyst less efficient for large molecules since it is diffusion limited. These supports used alone tend to plug rapidly, thereby deactivating the catalyst. However, the MCM-41 support material overcomes these flaws. In a preferred embodiment, the catalytic support material is solely ultra stable Y zeolite, MCM41 mesoporous material, β-zeolite, amorphous silica alumina or combinations thereof. A particularly preferred embodiment includes a single catalytic support material that is substantially all MCM-41. This material is mesoporous that is well-structured and has uniform morphology with high surface area. It also has low acidity as compared to beta and USY support materials. The invention includes the use of proper support material and a balance between acidic and metallic function with the proper distribution of metals throughout the support material. This is accomplished through the very well-structured morphology features of MCM-41 support material, which contains both acidic and metallic site that are accessible to the large hydrocarbon molecules found in VGO and DMO. For this reason, high conversion is achieved. Advantageously the lower acidity of MCM-41 as compared to other support materials drives conversion toward selectivity towards mid distillates and limits the production of undesirable light gases.

Problems solved by technology

ASA has a non-uniform structure with low acidity and high surface area.

The non-uniform structure tends to create acidic sites that are not available to large molecules, which leads to inferior performance of ASA alone as compared to MCM-41 or a combination of MCM-41 with ASA.

Similarly, the USY and β-zeolite supports suffer from drawbacks related to the microporous nature of the supports which makes the catalyst less efficient for large molecules since it is diffusion limited.

These supports used alone tend to plug rapidly, thereby deactivating the catalyst.

Advantageously the lower acidity of MCM-41 as compared to other support materials drives conversion toward selectivity towards mid distillates and limits the production of undesirable light gases.

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