| Abstract
| - It is often assumed that green petroleum coke behaves as aninert material in cocarbonizationwith coking coal blends and has no active behavior on the importantthermoplastic properties ofthe coal blend. This paper investigates that assumption. Theobjective of this study is to clarifyeffects arising when different petroleum cokes are added to a singlecoal or an industrial blend.The effects studied include changes during the pyrolysis stages ofthe cocarbonization, using abituminous coal. This was done to study if petroleum coke istotally inert at the plastic stage ofa given coal or there is an influence at the plastic stage. Afurther aim is to show howconventional and nonconventional techniques for petroleum cokecharacterization relate to itsactivity with the plastic stage of coal. A range of six petroleumcokes was used. The petroleumcokes were studied in terms of (a) optical texture, (b) FTIRspectroscopy, (c) hydrogen donorability, (d) thermogravimetric analysis of the pyrolysis stage, (e)free-swelling index, and (f)thermoplastic properties of blends made up of a bituminous coal andpetroleum coke. Evidencefor a significant activity of some petroleum cokes was assessed usingthe above techniques, whichcan be considered as nonconventional in petroleum cokecharacterization. A good correlationamong the parameters obtained from the above techniques/methods wasfound, indicating thatthe presence of unreacted and partially carbonized material, thehydrogen donor ability, therelative proportion of methyl and methylene groups, the amount ofvolatile matter released at atemperature range between 400 and 500 °C, the temperature of maximumvolatile matterevolution and, finally, the agglomeration degree of petroleum cokes canbe considered as importantfactors in the plastic properties of cocarbonization systems withcoking coals.
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