TITLE: Selective catalytic cracking of Fischer-Tropsch liquids to high value transportation fuels. Report number 24: Quarterly technical progress report for fourth quarter fiscal year 1992 (July 1--September 30, 1992)
AUTHOR: W. J. Reagan.
INST. AUTHOR: Amoco Research Center, Naperville, IL. Research and Development Dept.
SPONSOR: Department of Energy, Washington, DC.
PUB. TYPE: Technical Report
PUB. COUNTRY: United States
SOURCE: Department of Energy [DE], 1992, 29p.
NTIS ORDER NO.: DE95001939INW
Amoco Oil Company is investigating a selective catalytic cracking process to convert the Fischer-Tropsch gasoline and wax fractions to high value transportation fuels. The wax feedstock for this program, a commercial sample of fischer-Tropsch product from Sasol, is a high melting point, (>220 F), high boiling range (50% boiling above 1,000 F), largely paraffinic material. The wax feedstock readily converts over conventional fluid catalytic cracking (FCC) catalysts (85%+ conversion) to high yields of C(sub 4)-gas and naphtha. Three different types of zeolite catalysts and one amorphous cracking catalyst show wide variations of product yields as a function of wax feedstock conversion. The Beta and HZSM-5 zeolite catalysts have higher target light olefin (isobutylene and isoamylenes) yields than the Y zeolite sample. The HSZM-5 sample also produces the highest yields of propylene. Further work continues on various commercial and experimental HZSM-5 samples. There are some clear wax conversion variations among the samples. However, product selectivity differences are small and difficult to measure accurately. A series of rare earth exchanged Y zeolite catalysts show the expected rare earth effect: increased rare earth exchange gives higher naphtha and lower olefin yields. Several new FCC catalysts with low (10%) zeolite content have been prepared and analyzed. The zeolite Beta sample appears to have a lower hydrothermal stability than zeolite Y catalyst. The catalytic cracking test results from both the small scale test unit and the pilot plant suggest that very mild process conditions and low activity catalysts are needed to lower the overall wax conversion. The target light olefin yields vary with catalyst type and the process conditions.
REPORT NUMBER: DOE/PC/90057-T5
CONTRACT NUMBER: AC22-91PC90057