Petroleum cracking catalyst characterization

The characterization of petroleum cracking catalysts, with which a third of the world s crude oil is processed, presents a formidable analytical challenge. The catalyst particles are in the form of microspheres of 60-70 micron average diameter which are themselves composites of up to five different micron and submicron sized phases. In refinery operation the catalysts are poisoned by trace concentrations of nickel, vanadium and other contaminant metals. Due to the replacement of a small portion of equilibrium catalyst each day (generally around 1% of the total reactor inventory) the catalyst particles in a reactor exist as a mixture of differing particle ages, poisoning levels and activities. 

The technique of Imaging Secondary Ion Mass Spectrometry (SIMS) has proven to be very well suited to the characterization of fluidized petroleum cracking catalysts (FCC).(1-4) The ability to view... 

The catalyst chosen for this study was a low metal, equilibrium, commercial zeolite-containing cracking catalyst obtained from Phillips Petroleum Company. No specific characterization of the catalyst is available. 

Mitchell, M.M. and Moore, H.F., "Protocol Development For Evaluation of Commercial Catalytic Cracking Catalysts", Paper Presented at the Symposium on Preparation and Characterization of Catalysts before the Division of Petroleum Chemistry, Inc., American Chemical Society Meeting, Los Angeles, September 25-30 (1988). 

Since 1968 ICERP Ploiesti has been developed hydrofining technologies and catalyst systems for treating various petroleum cuts including blends of distillates with cracked feedstocks. The commercial hydrofining units in domestic refineries as well as those licensed in different countries are characterized by high service factors. 

Samples were characterized by XRD (Siemens D5000 XRD spectrometer), FE-SEM (Field Emission Scanning Electron Microscope, Hitachi S-4800), textural properties were determined by N2 adsorption/desorption experiments) and NH3-TPD (temperature-programmed desorption of ammonia). Catalytic properties of samples were tested in the cracking of a Bach Ho petroleum residue from Vietnam (370-500°C fraction) as heavy feedstock using a MAT 5000 micro activity testing system. The reaction conditions were 482°C, WVH=27, catalyst to feedstock ratio 3/1, reaction time 45 sec. 

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