In I/GCSE Chemistry, we will learn about Biotechnology & Chemical synthesis.
Biotechnology
In I/GCSE Chemistry, GM of microorganisms + biomass
PRO’s
- Bacteria breaks down wide range of sugars into ethanol
- Fungi breaks down biomass into glucose ethanol
- Yeast converts glucose into ethanol
- Yeats withstands high concs. of ethanol more profit
- Biomass used = less waste
PRO’s of GM
- In I/GCSE Chemistry, Waste biomass can’t be fermented normally b/c contains cellulose; cellulose can’t be converted by yeast, into ethanol.
- but G.M E.Coli converts cellulose into ethanol
- Yeast only breaks down glucose NOT other types of sugars available in plant feedstock’s
- but GM E.Coli converts all types of plant sugars into ethanol
Equation: All sugars --> ethanol + carbon dioxide
Opt temp: 35 degrees
Opt pH: pH6
Chemical synthesis
In I/GCSE Chemistry, Fermentation is too slow for making ethanol on a large scale.
Using ethane to produce high quality ethanol is quicker on an industrial scale = profitable
Crude oil/natural gas (non-renewable) contains ethane, which is cracked to form ethane.
Natural gas --> ethane --> [cracked] --> ethene + hydrogen released
Crude oil --> Naphtha --> [cracked] --> ethene + hydrogen released
Ethane --> Ethene + hydrogen
Ethene + steam [+ phosphoric acid catalyst] --> ethanol
In I/GCSE Chemistry, Catalyst: Phosphoric acid Temperature: 300 degrees Celsius Pressure: 60-70atm.
Atom economy: 100% (all atoms are used up) Energy costs: High temp + pressure required
Yield: 95% (b/c by-products are produced) Environment: oil spills
Un-reacted molecules are recycled. Health + safety: High temp + pressure be controlled
Purifying
In I/GCSE Chemistry, Difficult to remove water and obtain 100% ethanol. Zeolites are used as a dehydrating agent, which absorbs small water molecules and leave ethanol remaining.
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