9.5 Flashcards
What is crude oil?
A complex mixture of hundreds of thousand compounds
What is fractionation?
A process where crude oil is separated by the different boiling points
What happens when crude oil is heated to 500 degrees?
Most of its constituents vaporize, and substances with high boiling points remain, this is called Tar
What happens after crude oil is boiled?
The vapors make their way valve trays where they have to forces themselves
How do valve trays work?
Substances with high boiling points condense in the lower hotter trays and substances with low boiling points condense in the higher trays. The steams a withdrawn. These are called fractions
What are low boiling points due to?
Small molecules which have fewer electrons and weaker london forces
What are solvent extractions?
When a solvent is added to remove an impurity or to separate some useful products from a mixture
What are the 2 physical processes?
Fractionation and solvent extraction
What are the 2 chemical processes?
Cracking and reforming
What is cracking?
A chemical process in which larger molecules are broken down by heat and catalysts to produce smaller molecules
What is thermal cracking?
When cracking was only accomplished at high temperatures and pressures
What is the downside to thermal cracking?
It was massy and wasteful because it produced large quantities of carbon
What is catalytic cracking?
Breaking apart larger molecules in the presence of a catalyst
What is the upside to cracking?
Produces more desirable fractions and less tar and asphalt
What is hydrocracking?
A combination of catalytic cracking and hydrogenation
