Video Transcript
Which industrial process produces
alkenes from long-chain alkanes?
If we are producing alkenes from
long-chain alkanes, then we are breaking apart long-chain alkanes. This process is done because
alkenes are generally more useful than long-chain alkanes. We get a lot of the hydrocarbons
that we use from crude oil. But crude oil contains more
long-chain alkanes than are demanded. So, to shift this large supply of
long-chain alkanes to meet the demand of the shorter-chain alkenes, we need to break
apart the long-chain alkanes. This process is called
cracking.
Cracking is the process by which
less useful long-chain hydrocarbons, primarily alkanes, are broken down into more
useful short-chain hydrocarbons. These hydrocarbons may be mostly
alkenes, but in reality alkanes would also be produced. This is to do with making sure the
number of atoms are balanced. In the example shown, the
long-chain alkane has the molecular formula C14H30. When that molecule is broken down
or cracked, the only way for the total number of carbon atoms to be 14 and the total
number of hydrogen atoms to be 30 is if at least one alkane is produced with the
alkenes.
The process of breaking down a
long-chain alkane into shorter-chain alkenes and alkanes is called cracking. But since the process requires a
catalyst, more specifically, it is called catalytic cracking. So, the answer to the question
“which industrial process produces alkenes from long-chain alkanes?” is catalytic
cracking.
