Search

EP-4735562-A2 - HYDROCONVERSION OF A BIOMASS FEEDSTOCK TO HYDROCARBON FUELS IN A SLURRY PHASE CATALYST REACTOR

EP4735562A2EP 4735562 A2EP4735562 A2EP 4735562A2EP-4735562-A2

Abstract

Methods and reactor systems for conversion of bio-oils into renewable diesel, jet fuel, and gasoline. Phosphorus and metals containing feedstock is subjected to hydrodeoxygenation in a reactor comprising a solid catalyst suspended in a heavy oil.

Inventors

  • ABHARI, RAMIN
  • KOU, BO

Assignees

  • Chevron U.S.A. Inc.

Dates

Publication Date
20260506
Application Date
20240628

Claims (12)

  1. 1. A method for hydroconversion of a feedstock comprising fats, oils, and greases (FOG) comprising a. Introducing the feedstock to a reactor containing a catalyst slurried in a heavy oil b. Maintaining the reactor a temperature, a pressure, liquid hourly space velocity (LHSV), and a hydrogen supply rate to achieve conversion of the feedstock to a hydrocarbon product c. Removing from the reactor a vapor phase comprising the hydrocarbon product wherein the temperature is between 630 and 750 F the pressure is between 150 and 1,000 psig the LHSV is between 0.2/h and 10/h the hydrogen supply rate is between 3,000 and 15,000 SCF per bbl of feedstock and the vapor phase is partially condensed to recover the hydrocarbon product.
  2. 2. The method of Claim 1 wherein the feedstock comprises animal fats and plant-based oils with a combined phosphorus and metals content greater than 10 wppm.
  3. 3. The method of Claim 1 wherein the feedstock comprises bio-oils from fast pyrolysis or hydrothermal liquefaction of lignocellulosic biomass.
  4. 4. The method of Claim 1 wherein the catalyst comprises sulfided molybdenum.
  5. 5. The method of Claim 1 wherein the catalyst is present in the heavy oil at a concertation between 1 wt % and 20 wt %.
  6. 6. The method of Claim 1 wherein the heavy oil is a high temperature heat transfer fluid or vacuum gas oil.
  7. 7. The method of Claim 1 wherein the hydrocarbon product comprises heptadecane and octadecane.
  8. 8. The method of Claim 1 wherein the hydrocarbon product has a total acid number less than 1 mg KOH/g.
  9. 9. The method of Claim 1 wherein the hydrocarbon product is isomerized to provide hydrocarbon fractions suitable for use as diesel and/or jet fuel.
  10. 10. The method of Claim 1 wherein the reactor is a slurry bubble column reactor operating in the chum-turbulent regime wherein the hydrogen is supplied by a hydrogen-rich gas at a flow rate from about 7 cm/s to about 40 cm/s.
  11. 11. The method of Claim 1 wherein the slurry is withdrawn from the reactor and filtered to provide a filtrate substantially free of the phosphorus and metals in the feedstock.
  12. 12. The method of Claim 11 wherein in the filtrate is subjected to hydroprocessing in a fixed- bed reactor system for removal of remaining oxygen, sulfur, and nitrogen heteroatoms.

Description

Hydroconversion of a Biomass Feedstock to Hydrocarbon Fuels in a Slurry Phase Catalyst Reactor CROSS REFERENCE TO RELATED APPLICATIONS [001] This application is related to and claims the benefit of priority of U.S. Provisional Patent Appl. Ser. No. 63/510,651, filed on June 28, 2023, the disclosure of which is herein incorporated in its entirety. FIELD OF THE INVENTION [002] The present technology relates to biomass-based hydrocarbons, and more particularly, to hydrocarbon fuels. Specifically, the present invention relates to methods and reactor systems for conversion of bio-oils into renewable diesel, jet fuel, and gasoline. BACKGROUND OF THE INVENTION [003] Hydrodeoxygenation (HDO) of fats, oils, and greases (FOG) in fixed-bed reactor systems is a critical step in the renewable diesel production process. In this hydroconversion step, the 10 wt% or higher oxygen content of the FOG feedstock is removed as water and carbon oxides, transforming the fatty acids, fatty acid esters, and other oxygenates into hydrocarbons. FOG feedstocks that are considered most environmentally sustainable are byproducts of rendering and food processing industries such as inedible tallow and used cooking oils. Other such FOG feedstocks include byproducts of palm oil and bioethanol industries like palm oil mill effluent and distillers com oil. Bio-oils from pyrolysis and hydrothermal liquefaction represent another class of sustainable feedstock for potential hydroconversion in HDO reactor systems. [004] However, these environmentally sustainable feeds tend to contain relatively high levels of contaminants such as phosphorus, silicon, and chlorine compounds, as well as various solubilized metals and polymers (e.g. polyethylene), that impact performance of conventional HDO reactor systems. Specifically, the cited contaminants tend to deposit on the catalyst bed leading to pressure drop increase and catalyst deactivation. This in turn translates to costly production interruption associated with shutdown, catalyst change, and restart. [005] The prior art teaches various pretreatment methods for reducing the concentration of the contaminants to improve HDO efficiency. However, these pretreatment methods are only partially effective and most contaminants remain in the pretreated feed to the HDO reactor. As such, in order to prevent HDO reactor shutdown due to catalyst deactivation and bed plugging, many sustainable feedstock are largely excluded or included at relatively low amounts in HDO feeds. [006] Our US Patent 8,231,804 describes hydrogenation/hydrogenolysis of naturally occurring fatty acids and esters for production of paraffin compositions comprising of at least 75 wt% even carbon number paraffins. In the disclosed method, the mainly C12-C18 paraffin product remains in the liquid phase and has to be separated from the reactor catalyst by filtration. [007] There thus remains an unmet need for HDO methods and systems that are suitable for hydroconversion of low-value and waste FOG feedstocks, and bio-oils in general, such that reactor operation is not interrupted by catalyst deactivation and reactor pressure drop increase. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS [008] Fig l is a schematic diagram of an embodiment of the present invention for hydroconversion of FOG feedstock. SUMMARY [009] FOG feedstock with phosphorus and metals content greater than 10 wppm is subjected to hydrodeoxygenation in a reactor comprising a solid catalyst suspended in a heavy oil. The solid catalyst is preferably a sulfided molybdenum catalyst having an equivalent particle diameter less than 800 micron, and the heavy oil is a hydrocarbon with an initial boiling point of about 650 F. The method includes the steps of (a) introducing a feedstock comprising FOG and a hydrogenrich gas to the reactor at a rate to maintain a space velocity in the range of 0.2 to 10 h’1 (vol/hr FOG per vol reactor), (b) maintaining the reactor at a temperature in the 600-750 F range and a pressure between 150 and 1,000 psig, such that most of the feedstock mass is converted to hydrocarbons that are in vapor phase at reactor conditions, (c) withdrawing the vapors and unreacted hydrogen from the reactor, and (d) condensing the hydrocarbon vapors. In embodiments, the catalyst slurry is withdrawn from the reactor for separation of catalyst and/or separation of unconverted FOG species and non-vaporized reaction products from the heavy oil and/or catalyst. In embodiments, the separation of the catalyst is performed by filtration. In embodiments, the separation of the unconverted FOG species and non-vaporized reaction products is conducted by solvent extraction. In embodiments, the condensed hydrocarbon vapors and/or the non-vaporized hydrocarbon product is used as a diesel, jet fuel, or gasoline blendstock. In embodiments, the HDO condensed hydrocarbon vapors and/or the non-vaporized hydrocarbon product is subjected to isomerization prior to fractionation into d