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Reaction-Velocity Constants of Oil Cracking
very interesting. Accordingly, the data on the cracking of oil nreviooslv "resented hv the " *~ - ~ authors ( 3 ) were studied to see how the reaction velocities cumpared with those for the liglit iIydrOcarbOIlS. The data O D the cracking of pure hydrocarbons have shown that the reaction is p r o b a b l y ruonomolecular. and that, therefire, the reaction velocity, t, could he calculated most acciirately by the use of the monomolecular equation:
th, origirull charge,
temperature
merizaticin to products of higher boiling point than the original ,"."" fraction. The material remain= 28.8e-"".'""'"' ing after the removal of gas, gasoi%rriikv c i ~ k : ~ i d d ~ o ror1 h s data from /he decilrnpoline, and tar is taken as the unsifi:in of slraiaht-run naphthas and pressurechanged p r o d u c t , or a - x . Such an arbitrary definition of cracked "distillais giue ~in'espurallel ;1 that for unchauged product is obviously gas oil when plofled or1 the chartfor log k . us. 1 / T . somewhat in error ol,,ing to the A c*JWarison of these Petrolerzm frucfions fact that this material, ordinathe literature data for the pure hydrocarbons rily known as recycle stock, does shows that practically all of them fall on parallel not h a v e t h e s a m e c h e m i c a l lines, indicalirzy apPrrjzimatcly actitlaproperties as the original stock. G n d o u h t e d l y niolecular retion energy pw grarn mole decomposed. arrangements take place whichdo not markedly change the boiling point of tlic fraction. Yortnuately the error introduced is not as k = -]
