TITLE: Deactivation by carbon of iron catalysts for indirect liquefaction. Quarterly technical progress report, March 16, 1990-June 15, 1990. AUTHOR: C. H. Bartholomew. INST. AUTHOR: Brigham Young Univ., Provo, UT. SPONSOR: Department of Energy, Washington, DC. LANGUAGE: English PUB. TYPE: Technical Report PUB. COUNTRY: United States SOURCE: Department of Energy [DE], 10 Jan 91, 31p. NTIS ORDER NO.: DE91006700INW ABSTRACT: Although promoted cobalt and iron catalysts for Fischer-Tropsch (FT) synthesis of gasoline feedstock were first developed more than three decades ago, a major technical problem still limiting the commercial use of these catalysts today is carbon deactivation. This report describes recent progress in a fundamental, three-year investigation of carbon formation and its effects on the activity and selectivity of promoted iron catalysts for FT synthesis, the objectives of which are to: determine rates and mechanisms of carbon deactivation of unsupported Fe and Fe/K catalysts during CO hydrogenation over a range of CO concentrations, CO:H(sub 2) ratios, and temperatures; and model the rates of deactivation of the same catalysts in fixed-bed reactors. To accomplish the above objectives, the project is divided into the following tasks: (1) determine the kinetics of reaction and of carbon deactivation during CO hydrogenation on Fe and Fe/K catalysts coated on monolith bodies. (2) Determine the reactivities and types of carbon deposited during reaction on the same catalysts from temperature-programmed-surface-reaction spectroscopy (TPSR) and transmission electron microscopy (TEM). Determine the types of iron carbides formed at various temperatures and H(sub 2)/CO ratios using x-ray diffraction and Moessbauer spectroscopy. (3) Develop mathematical deactivation models which include heat and mass transport contributions for FT synthesis is packed-bed reactors. Progress to date is described. 48 refs., 3 figs., 1 tab. REPORT NUMBER: DOE/PC/90533-15 CONTRACT NUMBER: FG22-86PC90533 |