IKanes
saturated hydrocarbons with generalformula nHantz
hydrocarbon contain hydrogenand carbon only
saturated each carbon is bonded with maximum number of hydrogens
ossible no double bonds
cycloalkanes have generalformulaonHan H H
est
I a methane a
Ég ti ethane it propane
Ii.sc c.IIIaopentan
fractional distillation
alkanes are found in crude oil a mixtureofdifferentlengthhydrocarbons
column has a temp gradient
cooler at the top as vapour rises parts of the mixturecondense at different
temperatures becausethere are different chain lengths
and different boilingpoints fractions drawn off atdifferent
boiling points fractions drawn off at different levels
vapourised oil enterscolumnand rises throughthe trays
Longesthydrocarbonsdon'tvaporise and run down to the
bottom
Shortesthydrocarbons won't even condense at 200Candso
come off as gas at the top of the column
buses of fractions
Gas LPGand stove gas petrol cars kerosine jet fuel and heating
diesel oil diesel fuel is fuel oil usedinships and power stations
bitumen roofing and tarmac
cracking heavier fractions cracked into lighter more useful fractions
higher demand
e g 121426 244t C10422
dodecane ethene decane
2 types ofcracking thermal and catalyticcracking
thermal cracking hightempand pressureused 7100002 70atm ofpressure
productsmainly alkenes used to make polymerssuchas plastics
catalyticcracking hightemp not as highas for thermal cracking and
ightpressureused zeolite catalystused which helps to lower temp needed
products mainly aromatic hydrocarbons useful in fuels for vehicles
aromatic compounds contain benzene ring which is 6carbons in
ng with a delocalised electron system
catalyst lowers temp and pressureneeded lowerscostsandspeedsup
rocess
completecombustion of alkanes
alkanes burn in oxygencompletely plentifulsupplyof 02 to formCO2 H2o
alkanes are good fuels as most burn readily to producelargeamounts of
nergy used to power vehicles andmost of Britain's energy is madeusing th
mbustion of alkanes
e g Catino g 6.502 g 4002 g 542019
incomplete combustion of alkanes
alkanes burn with limited oxygenand produceCO and C soot
CO is poisonous bonds to haemoglobininblood and prevents
xygen bonding co can beremovedusingusing a catalyticconverter
e g Canio g 4.502 g a co g t SH20cg
CaH lo g 5.502 g 200 g 2002 g 5420 g
soot can cause breathingproblems make buildingsdirty and clog
engines
e 9 Canio g 2.50219 4 s 5420cg
saturated hydrocarbons with generalformula nHantz
hydrocarbon contain hydrogenand carbon only
saturated each carbon is bonded with maximum number of hydrogens
ossible no double bonds
cycloalkanes have generalformulaonHan H H
est
I a methane a
Ég ti ethane it propane
Ii.sc c.IIIaopentan
fractional distillation
alkanes are found in crude oil a mixtureofdifferentlengthhydrocarbons
column has a temp gradient
cooler at the top as vapour rises parts of the mixturecondense at different
temperatures becausethere are different chain lengths
and different boilingpoints fractions drawn off atdifferent
boiling points fractions drawn off at different levels
vapourised oil enterscolumnand rises throughthe trays
Longesthydrocarbonsdon'tvaporise and run down to the
bottom
Shortesthydrocarbons won't even condense at 200Candso
come off as gas at the top of the column
buses of fractions
Gas LPGand stove gas petrol cars kerosine jet fuel and heating
diesel oil diesel fuel is fuel oil usedinships and power stations
bitumen roofing and tarmac
cracking heavier fractions cracked into lighter more useful fractions
higher demand
e g 121426 244t C10422
dodecane ethene decane
2 types ofcracking thermal and catalyticcracking
thermal cracking hightempand pressureused 7100002 70atm ofpressure
productsmainly alkenes used to make polymerssuchas plastics
catalyticcracking hightemp not as highas for thermal cracking and
ightpressureused zeolite catalystused which helps to lower temp needed
products mainly aromatic hydrocarbons useful in fuels for vehicles
aromatic compounds contain benzene ring which is 6carbons in
ng with a delocalised electron system
catalyst lowers temp and pressureneeded lowerscostsandspeedsup
rocess
completecombustion of alkanes
alkanes burn in oxygencompletely plentifulsupplyof 02 to formCO2 H2o
alkanes are good fuels as most burn readily to producelargeamounts of
nergy used to power vehicles andmost of Britain's energy is madeusing th
mbustion of alkanes
e g Catino g 6.502 g 4002 g 542019
incomplete combustion of alkanes
alkanes burn with limited oxygenand produceCO and C soot
CO is poisonous bonds to haemoglobininblood and prevents
xygen bonding co can beremovedusingusing a catalyticconverter
e g Canio g 4.502 g a co g t SH20cg
CaH lo g 5.502 g 200 g 2002 g 5420 g
soot can cause breathingproblems make buildingsdirty and clog
engines
e 9 Canio g 2.50219 4 s 5420cg
