Chemical Engineering - Petroleum Refinery Engineering - Discussion

1) Iso paraffin easily cracked as compared to normal paraffin.

2) In FCCU for cracking molecules, we have to supply energy (endothermic) , in regeneration by the combustion of coke deposited on catalyst the heat is liberated (exothermic).

3) To NHT & DHDS, FCCU stream is feed for both as cracked Naptha & cracked diesel which contains high olefin content. Here if we carefully observe then we can found that the olefins are first cracked and then saturated easily in the presence of catalyst but with only thermal energy it is very difficult for the same cracking as compared to catalyst so that,

The statement "C" is the answer.

Thank you.

@Viettan:

1- The answer should be "C"; as olefins are produced in FCC and not decomposed (there is no olefins in the FCC feed).

2- Catalytic Cracking reaction is similar to thermal cracking reactions instead the use of a catalyst in FCC, so that's right that FCC is an endothermal reaction.

Catalyst regeneration is exothermal (it's widely known as a good advantage as it gives heat to the FCC gas oil and favorites the reaction).

Hope you find this helpful.

Here option (B) is right answer. Because regeneration required high temp and combustion of catalyst, heat is supplied, so craking and regeneration both are endothermic reactions.

@Shanker Tanneeru.

Please read the question carefully, option (c) is wrong because olefins cracks 1000 to 10000 time in catalytic cracking than thermal cracking.

Option (c) is wrong because olefins crack 1000 to 10000 times in catalytic cracking than thermal cracking.

So the answer should be (C).

Option B is also the right statement. Because, in FCCU The cracking reaction is endothermic and regeneration reaction exothermic.

Hi, I agree with @Veeramanigandan and @Mohamed Amer.

And you? Please help me to get a clear explanation. Thanks!

The Correct and is (C). Because olefins crack 1000-10000 times faster in catalytic cracking than thermal.

See the question its pick out the wrong statement?

So how the answer will be B? Explain.

Catalytic cracking is endothermic and regeneration reaction is exothermic.