Does the petrochemical industry rely on thermal or catalytic cracking? (1 Viewer)

EggplantLord

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Does the petrochemical industry rely on thermal or catalytic cracking for ethene production? Why?


Thnx:awesome:
 

strawberrye

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Usually catalytic because it is lower energy and less costly-->i.e. more profitable, however thermal cracking may be viable in areas where there is renewable energy source-i.e. hydroelectricity for example.
 

He-Mann

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Assertion: The petrochemical industry relies on catalytic cracking for ethylene production.

Comparison and reasoning: thermal cracking is the decomposition of long-chain hydrocarbons to smaller-chain hydrocarbons under high temperatures without air. This is an expensive process due to the amount of energy required (high temperatures) and inefficiency as these long-chain hydrocarbons are splitted at random intervals yielding unpredictable products.

In contrast, catalytic cracking is an alternative and more desired as it uses a catalyst (zeolite) which lowers the activation energy thereby increasing reaction rate. As a result, lower temperatures can be used (lesser energy requirements), which makes the process less costly. Furthermore, this form of 'cracking' is more consistent and therefore produces what we need: ethylene.

Conclusion: catalytic cracking is the answer!
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This seems like a good general knowedge question so I did a quick Google search of 'catalytic cracking vs thermal cracking', picked out 3 sources and summarised above.
 

ProdigyInspired

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I thought thermal cracking was more effective for alkanes which are longer than 25C? However it's probably more expensive due to the amount/cost of energy for the high temps.

Ahmad Shah:

 This [Catalytic Cracking] process uses less heat than THERMAL cracking, but it cannot decompose large molecules completely into ethylene, so it is insufficient in meeting the demands of the industry.

Thermal:
 The alkanes are decomposed completely into ethylene and other short chains.
 The use of steam is that is allows for easy flow of hydrocarbon gases, it dilutes the mixture to create smooth reactions, and it removes carbon deposits in the metal tubes.
 
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