Alcohol / Ethanol

  We are all familiar with ethanol, C2H5OH, the drug that society accepts the use of through drinks. I hope, we are also familiar with the many problems that it brings. Social problems aside, ethanol harms and damages the body as it is a toxic and a poison. The body also breaks it down as follows: C2H5OH is oxidised to CH3CHO (ethanal) which is also oxidised to CH3COOH (ethanoic acid) by an enzyme called 'alcohol dehydrogenase'. The ethanoic acid can be reacted with oxygen ...

Ageing Wine

  We have all heard that wine gets better with age, but why?   To start with, it doesn't really improve, it's Chemistry changes. Substances such as .... .... Tannins precipitate and oxidised alcohol (ie, carboxylic acids) combine with ethanol to form esters - which improve the wines aroma. So does it taste better? Well this will depend on other things, such as the type of grape. This posting was adapted from an article in 'Focus Magazine' on sale in June 2010 on page 77.

Carbon Neutral Biofuels

  What do we mean by Carbon Neutral? The CO2 produced in its combustion and fermentation will equal the CO2 used in its production. Ethanol is sometimes touted as a Carbon Neutral bio-fuel. Why? Well, to make the ethanol a plant photosynthesizes to produce sugar. 6CO2 + 6H2O → C6H12O6 + 6O2   Sugar is then fermented to produced ethanol. C6H12O6 → 2C2H5OH + 2CO2   When ethanol is combusted, the CO2 evolved equals the CO2 used in its production. 2C2H5OH + 6O2 → 4CO2 + 6H2O Simple? It does look that ...

Fuel from bugs

There are two key problems with using fossil fuels. They produce CO2 on combustion and they are non renewable. This posting aims to deal with the latter - the non renewable problem. Fossil fuels will run out someday soon so we really need to think about developing sustainable fuels. Ethanol, produced by fermentation of sugar cane has been heralded as a possible answer to the problem. We are probably all familiar with biofuels and Brazil seems to successfully use gasohol. However, ...