Production of alcohols Flashcards
Name the two ways to produce alcohol
Hydration of alkenes or fermentation of glucose
Which method of alcohol production is used in industry
Hydration of alkenes
What are the conditions for hydration of ethene to form ethanol
Phosphoric acid catalyst
300 degrees c
60atm pressure
Conditions for fermentation of glucose to form ethanol
Yeast
Anaerobic conditions
30-40
The enzyme in yeast is what causes the conversion - the aforementioned conditions are optimal conditions for function of that enzyme
Why is 30-40 degrees c the optimum temperature for fermentation of glucose
Fast enough rate of reaction but not too hot that enzymes dentaure - hydrogen bonds break, changing the shape of the active site
How is ethanol produced by fermentation purified
(fRACTIONAL) Distillation
What is a biofuel
A fuel made from biological matter
How can ethanol be a biofuel
If it is made from fermentation of glucose
Explain using equations how the use of ethanol is, in theory, carbon neutral
6CO2 + 6H20 > C6H12O6 + 6O2
During lifespan of the plant, 6 moles of CO2 are removed from the atmosphere
C6H12O6> 2C2H5OH + 2CO2
When bioethanol is made 2 moles of CO2 are produced
2C2H5OH + 4O2 > 4CO2 + 6H2O
During burning of ethanol, 4 moles of CO2 are released
Overall net release of CO2 = 0
What sort of places is ethanol being used as a biofuel
Places where lots of sugar cane is grown
Why, in reality, is use of bioethanol as a fuel not 100% caron neutral
Fossil fuels are used
>transporting the fuel, materials or equipment
> in fertilisers (making, transporting, ingredients) to grow the sugar cane
What are the advantages of using bioethanol
> Renewable so more sustainable than crude oil
Classed as carbon neutral
What are the disadvantages of using bioethanol
> Expensive to convert traditional petrol engines to take fuels with high conc of ethanol
Land that could have been used to grow food is now being used to make fuel and this could cause food shortages
