Gasoline cracking

Gas oil and gasoline cracking are assumed to be second order and first order processes, respectively. It was found that W ranges between 0.1 and about 0.7. 

It is evident that ZSM-5 is more active for gasoline cracking as 23.7 wt% L.P.G. + dry gas was produced compared with 18.2 wt% for REHY. As is commonly observed, a lower coke yield was also produced with ZSM-5. 

Cracking Gas, This is produced when heavy petroleum is cracked to produce gasoline. Cracking gas consists, in a large part, of olefins particularly ethylme propylene. It is being used more and more for the manuf of glycol glycerin which are nitrated to produce expls such as NGc, NG, Ethanolamine Nitrates (See under Aminoethanol... 

To take into account this particular effect of coke ori selectivity it is necessary to use different 4>jj tor each reaction. A direct determination of all parameters Aij, Bij, kij by optimisation would be impossible because of their targe number. The analytic resolution of the equations giving jj is r>ot possible because of the existence of successive reactions. An experimental method to obtain the 4>ij functions may be to get data with and without initial coke content at lower conversions (for 4>ij) and to study the gasoline cracking (for 4>2j)... 

Radical processes are used heavily in chemical industries, particularly in the petrochemical industry. One such example is the process called cracking. In Chapter 4, we mentioned that cracking of petroleum converts large alkanes into smaller alkanes that are more suitable for use as gasoline. Cracking is a radical process ... 

According to the three lump model, the rates of gas oil cracking and gasoline cracking may be written as ... 

The first point confirms the fact that secondary reactions, namely gasoline cracking, become significant after a certain conversion level The second point, describing the temperature effect on gasoline yield is better revealed by considering the selectivity to gasoline. 

Gasoline cracking rate constant in the 3-lump model (cm /gc. s)... 

Rate constant for gasoline cracking to C-lump (cm /gcat-s)... 

Make gasoline Make gasoline Eliminate fuel oil Cracked gasoline Cracked gasoline Cracked gasoline 300-700 400-800 300-500 880-950 960-1020 890-960 ... 

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