TITLE: Separation of Fischer-Tropsch wax from catalyst using supercritical fluid extraction. Quarterly technical progress report, April 1, 1996--June 30, 1996.

AUTHOR: P. C. Joyce;   M. C. Thies.

INST.  AUTHOR: Clemson Univ., SC. Dept. of Chemical Engineering.

SPONSOR: Department of Energy, Washington, DC.

LANGUAGE: English

PUB.  TYPE: Technical Report

PUB.  COUNTRY: United States

SOURCE: Department of Energy [DE],  1996,  19p.

NTIS ORDER NO.: DE97050213INW

ABSTRACT:

The objective of this research project is to evaluate the potential of SCF extraction for separating the catalyst slurry of a Fischer- Tropsch F-T) slurry bubble column (SBC) reactor into two fractions: (1) a catalyst-free wax containing less than 10 ppm particulate matter and (2) a concentrated catalyst slurry that is ready for recycle or regeneration.  The wax will be extracted with a hydrocarbon solvent that has a critical temperature near the operating temperature of the SBC reactor, i.e., 200-300(degrees)C. Initial work is being performed using n-hexane as the solvent. The success of the project depends on two major factors. First, the supercritical solvent must be able to dissolve the F-T wax; furthermore, this must be accomplished without entraining the solid catalyst. Second, the extraction must be controlled so as not to favor the removal of the low molecular weight wax compounds, i.e., a constant carbon-number distribution of the alkanes in the wax slurry must be maintained at steady-state column operation. To implement our objectives, the following task structure is being implemented: Task 1 equilibrium solubility measurements; Task 2 thermodynamic modeling; and Task 3 process design studies. Progress reports are presented for each task.

REPORT  NUMBER: DOE/PC/94219-T7

CONTRACT  NUMBER: FG22-94PC94219