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US-12618013-B2 - Catalyst and process for deoxygenation and conversion of bio-derived feedstocks

US12618013B2US 12618013 B2US12618013 B2US 12618013B2US-12618013-B2

Abstract

A catalyst and process for the deoxygenation and conversion of bio-derived feedstocks. The catalyst comprises a silica-alumina support having specifically defined physical properties and a molybdenum component but a material absence of nickel. The process involves the processing of a bio-derived feedstock having an oxygen content to yield a conversion product having an exceptional distillation profile and physical properties and a substantially reduced oxygen content.

Inventors

  • Opinder Kishan Bhan

Assignees

  • SHELL USA, INC.

Dates

Publication Date
20260505
Application Date
20220722

Claims (6)

  1. 1 . A deoxygenation catalyst useful in the conversion of bio-derived feedstocks, wherein said catalyst consists essentially of: a support, comprising a silica-alumina component, wherein said support has a mean pore diameter in a range of from 40 Å to 200 Å and a nitrogen surface area in a range of from 200 m 2 /g to 500 m 2 /g, and exhibits Raman spectral characteristics such that its Raman spectrum has at least one Raman peak within the Raman region of from 1300 cm −1 to 1500 cm −1 ; and a molybdenum component in an amount such that said catalyst comprises from 10 wt. % to 20 wt. % molybdenum, calculated as metal, regardless of its actual state, and based on the total weight of said catalyst, wherein said catalyst has a material absence of nickel and a material absence of cobalt, wherein said silica-alumina component of said support comprises from 2 wt. % to 15 wt. % of silica and from 85 wt. % to 98 wt. % alumina, wherein said material absence of nickel is less than 1 wt. % nickel, calculated as metal and based on the total weight of said catalyst, and wherein said material absence of cobalt is less than 1 wt. % cobalt, calculated as metal and based on the total weight of said catalyst.
  2. 2 . The catalyst as recited in claim 1 , wherein said material absence of nickel is less than 0.1 wt. % nickel, calculated as metal and based on the total weight of said catalyst.
  3. 3 . The catalyst as recited in claim 1 , wherein said material absence of cobalt is less than 0.1 wt. % cobalt, calculated as metal and based on the total weight of said catalyst.
  4. 4 . The catalyst as recited in claim 1 , wherein said silica-alumina component of said support comprises silica in a range of from 4 wt. % to 10 wt. %, and wherein said mean pore diameter of said support is in a range of from 60 Å to 120 Å.
  5. 5 . A deoxygenation catalyst useful in the conversion of bio-derived feedstocks, wherein said catalyst consists essentially of: a silica-alumina support having from 2 wt. % to 15 wt. % of silica and from 85 wt. % to 98 wt. % alumina and a mean pore diameter in a range of from 40 Å to 200 Å and a nitrogen surface area in a range of from 200 m 2 /g to 500 m 2 /g, wherein the support exhibits Raman spectral characteristics such that its Raman spectrum has at least one Raman peak within the Raman region of from 1300 cm −1 to 1500 cm −1 ; and molybdenum present in an amount in the range of from 10 wt. % to 20 wt. % molybdenum, calculated as metal, regardless of its actual state, and based on the total weight of said catalyst.
  6. 6 . The catalyst as recited in claim 5 , wherein said silica-alumina support has from 4 wt. % to 10 wt. % silica and from 90 wt. % to 96 wt. % alumina, and wherein said mean pore diameter of said silica-alumina support is in a range of from 60 Å to 120 Å.

Description

This present application is a divisional application which claims the benefit of U.S. Non Provisional patent application Ser. No. 14/886,150 filed Oct. 19, 2015, which claims priority from U.S. provisional application No. 62/066,590, filed 21 Oct. 2014, the entire disclosure of which is incorporated herein by reference. FIELD OF THE INVENTION This invention relates to a catalyst and process for the deoxygenation and conversion of bio-derived feedstocks. BACKGROUND OF THE INVENTION In recent decades, for a variety of reasons, there has been increased interest in the development and use of biofuels as potential alternatives to fossil fuels. A biofuel is a fuel that is produced from material having a living source, such as plant-derived and animal-derived materials. These bio-derived materials from which the biofuels can be produced are generally animal fats and vegetable oils. Some examples of potential materials that can be processed as a bio-derived feedstock include plant-based fats and oils, such as, coconut oil, palm kernel oil, palm oil, cotton seed oil, olive oil, corn oil, soybean oil, peanut oil, flaxseed oil and any other plant or vegetable oil. Many of the bio-derived materials having potential use as a feedstock material for the production of a biofuel comprise molecules having exceptionally high boiling temperatures making them unsuitable, without further processing and modification, for use in combustion engines. These bio-derived materials typically are made up of large percentages of saturated and unsaturated long-chain fatty acids. Thus, they are not only high boiling temperature materials, but they also contain, relative to fossil fuels, large percentages of oxygen due to the carboxyl and other oxygen-containing moieties of the fatty acids. It is desirable to use a catalytic approach to processing the above-mentioned bio-derived materials to yield a variety of conversion products having lower boiling temperatures that allow for their use as one or more types of fuel. It also can be desirable or necessary to remove the oxygen from the bio-derived feedstocks before they or derivative products are used as a biofuel. One problem with catalytic processing of bio-derived feedstocks having high oxygen content is that the oxygen is removed predominantly by way of a decarboxylation reaction instead by a deoxygenation reaction. The decarboxylation reaction involves, for example, removal of the carboxyl group (—COOH) from the fatty acid to yield carbon dioxide (CO2) and a hydrocarbon (R—H); while, on the other hand, the deoxygenation reaction involves breaking the carbon-hydrogen bonds of the fatty acid molecule and replacing the broken bonds with hydrogen. The decarboxylation reaction can be incomplete and further can undesirably yield carbon monoxide instead of carbon dioxide. U.S. Patent Pub. No. 2011/0166396 discloses a process and hydrodeoxygenation catalyst that provide for making diesel and naphtha fuels from feedstocks derived from renewable organic material and having oxygen-containing components. The hydrodeoxygenation catalyst that is disclosed in this publication is a supported molybdenum catalyst having a molybdenum content between 0.1 to 20 wt %, preferably, between 0.1 to 10 wt %, and without a co-promoter metal. The support is selected from alumina, silica, titania, and combinations thereof, but the support does not contain precipitated silica-alumina that contains a range of silica. Instead, the preferred support is an amorphous alumina. The support also has a bimodal structure with at least 2% of its total pore volume, preferably, at least 10%, and more preferably at least 15%, being within the pores having a diameter above 500 angstroms (macropores). The teachings of US 2011/0166396 are focused on an alumina support and the retention of large pores by using no or only a small amount of acid when preparing the alumina support of its catalyst. There is no mention in this publication of the mean pore diameter of its support or that there is any significance to its mean pore diameter other than it is important for the amorphous alumina support to have a significant pore volume in its macropores and it is bimodal. As it has been shown, it is desirable to have a catalyst and process that provide for the processing of bio-derived feedstocks to yield conversion products having boiling temperatures in the gasoline and middle distillate boiling ranges, with low amounts of high-boiling temperature components, that suitably can be used as fuels in various combustion engines and other applications. SUMMARY OF THE INVENTION Accordingly, provided is a catalyst useful in the deoxygenation and conversion of bio-derived feedstocks. The catalyst comprises a support comprising a silica-alumina component impregnated with molybdenum, wherein the support has a mean pore diameter in the range of from 40 Å to 200 Å and a nitrogen surface area in the range of from 200 m2/g to 500 m2/g. The catalyst further co