Bayraktar, OğuzKugler, Edwin L.2016-07-112016-07-112004Bayraktar, O., and Kugler, E. L. (2004). Temperature-programmed reduction of metal-contaminated fluid catalytic cracking (FCC) catalysts. Applied Catalysis A: General, 260(1), 125-132. doi:10.1016/j.apcata.2003.10.0130926-860Xhttp://doi.org/10.1016/j.apcata.2003.10.013https://hdl.handle.net/11147/1879A temperature-programmed reduction study of equilibrium fluid catalytic cracking (FCC) catalysts has shown three hydrogen-consumption peaks associated with contaminanted metals. A low-temperature peak, located near 510°C, is produced by the reduction of several components in the catalyst. Highly-dispersed vanadium contributes to this peak. A high-temperature peak, located near 800°C, is produced by reduction of nickel aluminate or nickel silicate compounds. A linear relationship exists between the area of the high-temperature peak and nickel concentration on equilibrium catalysts. An intermediate-temperature peak, located near 690°C, appears to be related to some form of vanadium compound. The intermediate-temperature peak does not occur on low-vanadium-concentration equilibrium catalysts, but is observed at higher vanadium-contamination levels. The presence of the 690°C peak was found by deconvoluting hydrogen-consumption data. The existence of this intermediate-temperature peak was proven by external reduction of highly-contaminated equilibrium catalyst at 500 and 700°C. External reduction at 500°C removes the low-temperature peak from the temperature-programmed reduction (TPR) spectrum. External reduction at 700°C removes both the low-temperature and intermediate-temperature peaks from the TPR spectrum. The difference in spectrum between calcined and 700°C reduced samples shows a clear spectrum with only the low and intermediate-temperature peaks present.eninfo:eu-repo/semantics/openAccessCatalystsPretreatmentTemperature-programmed reductionFluidized catalytic cracking catalystsNickelVanadiumArticle2-s2.0-154231683410.1016/j.apcata.2003.10.01310.1016/j.apcata.2003.10.013