Methods and apparatus for separating Fischer-Tropsch catalysts from liquid hydrocarbon product

• US 6,217,830 B1
• Filed: 02/16/2000
• Issued: 04/17/2001
• Est. Priority Date: 10/27/1993
• Status: Expired due to Fees

• Current Assignee: North Carolina State University (University of North Carolina System)
• Original Assignee: North Carolina State University (University of North Carolina System)
• Inventors: Kilpatrick, Peter K., Roberts, George W.
• Primary Examiner(s): PADMANABHAN, SREENIVASAN
• Application Number:
  US09/505,216
• Time in Patent Office: 426 Days
• Field of Search: 208/950, 518/700, 518/705, 518/706, 518/709, 518/715, 422/140, 422/224, 422/227, 422/231, 422/239, 422/228, 422/275
• US Class Current: 422/140
• CPC Class Codes: B01J 8/228 externally, i.e. the particles leaving the vessel and subsequently re-entering it
• CPC Class Codes: C07C 1/0425 Catalysts; their physical properties
• CPC Class Codes: C07C 1/0485 Set-up of reactors or accessories; Multi-step processes
• CPC Class Codes: C07C 7/10 by extraction, i.e. purification or separation of liquid hydrocarbons with the aid of liquids
• CPC Class Codes: Y02P 20/54 using solvents, e.g. supercritical solvents or ionic liquids

Abstract

A method of separating a Fischer-Tropsch catalyst from the output slurry of a Fischer-Tropsch bubble column reactor, where the slurry comprises Fischer-Tropsch catalyst particles and liquid hydrocarbon product is disclosed. The method comprises contacting a compressed hydrocarbon solvent (e.g., a supercritical hydrocarbon solvent, or liquid hydrocarbon solvent which may be at near supercritical conditions) with the output slurry at a temperature and pressure where the liquid hydrocarbon product is soluble in the solvent to form a concentrated slurry phase containing the catalyst particles, and an enriched solvent phase containing liquid hydrocarbon product. This contacting step is then followed by the step of separating the concentrated slurry from the enriched solvent. Apparatus for carrying out the method of the invention is also disclosed.

Claims

1. An apparatus for making a hydrocarbon product by a Fischer-Tropsch reaction, comprising:

a Fischer-Tropsch slurry bubble column reactor for reacting a synthesis gas in the presence of Fischer-tropsch catalyst particles to produce a slurry comprising liquid hydrocarbon product and Fischer-Tropsch Catalyst particles in said reactor;

a slurry output line connected to said slurry bubble column reactor for providing an output of said slurry;

a compressed hydrocarbon solvent supply;

contacting means connected to said slurry output line and said compressed hydrocarbon solvent supply for contacting said compressed hydrocarbon solvent with said output slurry at a temperature and pressure wherein said liquid product is soluble in said solvent to form a concentrated slurry phase containing said catalyst and an enriched solvent phase containing liquid hydrocarbon product;

first separating means connected to said contacting means for separating said concentrated slurry from said enriched solvent; and

recycling means connected to said first separating means for recycling said concentrated slurry to said Fischer-Tropsch slurry bubble column reactor.

2. An apparatus according to claim 1, further comprising second separating means connected to said first separating means for separating a first fraction of said liquid hydrocarbon product from said enriched solvent to form a first hydrocarbon product fraction and a first depleted solvent.

3. An apparatus according to claim 1, wherein said contacting means comprises a mixer.

4. An apparatus according to claim 1, wherein said first separating means comprises a settler.

5. An apparatus according to claim 1, wherein said first separating means comprises a centrifuge.

6. An apparatus according to claim 1, wherein said contacting means and said first separating means together comprise a continuous countercurrent contactor.