Cyclic metal impregnation

Since the method of metal impregnation will also have a large impact on the profile of vanadium deposition of the catalyst, we clearly need to review this aspect of catalyst testing. Via cyclic metal impregnation and catalyst deactivation, we can approach "Real-World" conditions far better. (Table VII.)... 

The route of catalyst deactivation via a cyclic metal impregnation and deactivation method has produced significant improvements in approaching realistic vanadium and nickel profiles over the catalyst particles. From electron microprobe analyses of Ni and V loaded catalyst it has been established that after pore volume saturation, Ni and V are rather homogeneously distributed over the catalyst. 

Properties Mitchell Method Cyclic Metals Impregnation Cyclic Propylene Steam... 

The selectivity improvements of the SAM-200 containing ULTIMA catalysts are especially pronounced when the catalyst is metallated to simulate the equilibrium catalyst conditions in a high metals environment arising from processing of heavy feeds in the FCC Unit. Table 5 summarizes Riser Pilot Plant (DCR) results of a competitive Resid Catalyst versus ULTIMA-445 after Cyclic Metals Impregnation of the catalysts to 5000 ppm Ni+V. 

Catalysts Cyclic Metals Impregnation and steaming (CPS). Test Conditions MAT, fixed-bed, 527°C Reactor Temperature, 30 s Contact Time, Aromatic feed, 0.948 g/cc 15"C, R.I. 

Interparticle mobility is proven by electron microprobe scans of cyclic metal impregnated (CMI)[6] Residcat 767Z4+ which incorporates RV4+ technology. Since the catalyst and the RV4+ were simultaneously exposed to the metals during the CMI procedure, the rate of deposition of vanadium on the catalyst and trap surfaces should be similar. However, the catalyst particles, contain virtually no detectable vanadium. In contrast, the RV4+ particles containing the Active Trap Component are high in vanadium. This is another indication of particle to particle vanadium mobility[6]. ... 

Finally, the V concentrations on particle surfaces of sample CPS were only slightly higher than those determined by AA while no Ni was detected. Thus, we conclude that metals in the particles of sample CPS are distributed throughout the particles and more homogeneously than in CD samples. These results are roughly in line with what has been reported [5] regarding metal distribution in equilibrium catalysts and catalysts prepared by cyclic deactivation and impregnation. 

The properties of a commercial FCC catalyst modified with V and Ni by cyclic deactivation (CD) and impregnation-based laboratory procedures were compared to the properties of equilibrium catalysts tested in a commercial FCC unit. Principle differences were the degree of metal aging and concentration profiles in the catalyst particles. The CD procedure produced properties in the catalyst that were comparatively closer to those exhibited by the equilibrium catalysts. 

Endolign - This is an implantable continuous carbon fibre composite which is used for the replacement of metals in high sustained or cyclic load applications. The ability to control fibre direction means that mechanical properties can be tailored for specific applications. It is supplied as a pre-impregnated tape or as rods that can be heat-formed through processes such a composite flow moulding. 

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