Open AccessTechnology development for iron Fischer-Tropsch catalysis. Quarterly technical progress report No. 4, July 1, 1995--September 30, 1995
Author(s) -
Burtron H. Davis
Publication year - 1996
Language(s) - English
Resource type - Reports
DOI - 10.2172/225068
Subject(s) - fischer–tropsch process , catalysis , chemistry , hydrogen , carbon monoxide , copper , syngas , inorganic chemistry , selectivity , organic chemistry
The affect of copper promotion on the activity and selectivity of hydrogen pretreated, precipitated iron Fischer-Tropsch catalysts was studied. Fischer-Tropsch synthesis was carried out in the slurry phase in one in one liter continuous stirred tank reactors at a space velocity of 3.lNL h{sup {minus}1} g{sup {minus}1}(Fe), H{sub 2}:CO = 0.7 at either 270{degree}C or 230{degree}C. Catalysts with atomic compositions relative to iron of 10OFe/4.4Si/l.OK and 10OFe/4.4Si/2.6Cu/l.OK were used at 270{degree}C and catalysts with the compositions of 100Fe/4.4Si/4.2K and 10OFe/4.4Si/2.6Cu/4.2K were used at 230{degree}C. XRD and Moessbauer spectroscopy both show that the 10OFe/4.4Si/2.6Cu/l.OK catalyst contained approximately 24% {alpha}-Fe with the remainder Fe{sub 3}O{sub 4} after a 24 h pretreatment with hydrogen at 220{degree}C. Copper promotion was found to substantially increase the activity and productivity of the catalysts. Catalysts promoted with copper reached maximum activity within 100 h of synthesis while catalysts with no copper went through an induction period. The activity of the hydrogen pretreated 10OFe/4.4Si/2.6Cu/1.0K catalyst operated at 270{degree}C was comparable to the activity of the the 100Fe/4.4Si/l.OK catalyst after pretreatment with carbon monoxide or syngas at one atmosphere pressure. However, the activity of the hydrogen pretreated 1O0Fe/4.4Si/2.6Cu/4.2K catalyst at 230{degree}C was found to be substantially lower than the same catalyst pretreated with carbon monoxide or syngas at one atmosphere pressure