Ramsbottom carbon

Figure 2-6. Ramsbottom Carbon Residue versus Conradson Carbon Residue. (Copyright ASTM D-524. Reprinted with permission.)...

Feed residue coke is the small portion of the (non-residue) feed that is directly deposited on the catalyst. This coke comes from the very heavy fraction of the feed and its yield is predicted by the Conradson or Ramsbottom carbon tests. 

As work began on the process, it quickly became apparent that the extraordinary catalyst properties required for the process were not then available, and even with a superior catalyst, consumption would undoubtedly be severe. Figure 3 shows how Ramsbottom Carbon and nickel plus vanadium vary in the same reduced crude oils. All levels are very high far beyond anything normally encountered in a gas oil feedstock. 

Because of the high coke-forming tendencies of reduced crude, mainly due to a high concentration of Ramsbottom Carbon, the adverse effects of nickel appear to be somewhat moderated in the trip up the riser. Therefore, nickel does not appear to be quite as harmful as first anticipated. 

RCC process catalysts with metals contents as high as 12,300 ppm nickel plus vanadium, plus 6,000 ppm of iron, have operated in the 200 B/D demonstration unit on feedstocks containing up to 84 ppm nickel plus vanadium.(4,5) Presently in our refinery, when metals levels are at still higher levels, the reduced crude is first processed in the Ashland ART unit, where some 85-95% of the metals and 75% of the Ramsbottom Carbon are removed.(6)... 

Two schools of thought still abide on this unresolved issue. The RCC unit operates with a significant partial pressure, gives rather low coke yields in relationship to Ramsbottom Carbon in the feed, and makes an unusually high research octane.(5)... 

G. HIGH CARBON VALUES FOR MICRO METHOD, CONRADSON, AND RAMSBOTTOM CARBON NUMBER DETERMINATIONS... 

The following information can be obtained from Micro Method, Conradson and Ramsbottom carbon values ... 

Residuum type 1000T (LV Gravity CAPI) Sulfur (wi. %) Nitrogen (wt. %) Ramsbottom carbon (wl. %) Metals (ppm) ... 

Coke number used, particularly in Great Britain, to report the results of the Ramsbottom carbon residue test (q.v.), which is also referred to as a coke test. 

Thermal coke the carbonaceous residue formed as a result of a noncatalytic thermal process the Conradson carbon residue the Ramsbottom carbon residue. 

In processing VGO it has been argued that the heavy poly-aromatic structures characterised by the Ramsbottom Carbon Residue (RCR, Table 1) can be considered as coke precursors [8]. An increase of the boiling point of those structures via condensation reactions or dehydrogenation reactions is responsible for coke deposition onto the catalyst. In order to increase our level of understanding of these processes we consider first the effects of catalyst parameters on the coke formation. 

Ramsbottom carbon residue on 10% distillation residue, % mass, max. D524 0.15 0.35 ... 

Tests for Conradson carbon residue (ASTM D-189, IP 13), Ramsbottom carbon residue (ASTM D-524, IP 14), the microcarbon carbon residue (ASTM D4530, IP 398), and asphaltene content (ASTM D-893, ASTM D-2006, ASTM D-2007, ASTM D-3279, ASTM D-4124, ASTM D-6560, IP 143) are sometimes included in inspection data on petroleum. The data give an indication of the amount of coke that will be formed during thermal processes as well as an indication of the amount of high-boiling constituents in petroleum. 

In the Ramsbottom carbon residue test (ASTM Test Method D524, IP 14), the sample is weighed into a glass bulb that has a capillary opening and... 

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