1)Industrial production of ethanol

1)Industrial Production of Ethanol




sugar cane



The rapid increase of the use of motor cars has led to a large demand for producing high quality yet cheaper fuel. Fossil fuels such as crude oil, petroleum, coal, natural gas are non-renewable, non-biodegradable and produce pollution. In addition, they are most likely to end in the next 30 years depending on the rates of consumption. When this supply runs out we will face shortage of fuel and vital chemicals for manufacturing and heating purposes.

Consequently, we anxiously search for alternative sources to replace fossil fuel with renewable sources, as only limited supplies are remaining.

Scientists are experimenting with other sources to produce energy. So far, the best solution known is “Biomass” an organic renewable matter produced from plants. Cellulose found in wood, leaves and plant cell walls is an example of a biomass condensation polymer produced from the monomer glucose then processed to give ethanol.

Industrial Production



Ethanol can be made from corn, sugar cane and other waste products depending on the manufactured country. However, sugar cane is the most suitable source as it contains an abundant amount of sugar compared to other resources. Before started the process of producing ethanol, the following is required

-carbohydrate source (sugar cane,starch,corn)                                                                                                                     

-live yeast that reacts

-Constant temperature from 22 -25   C

-Anaerobic conditions (no oxygen) because if O2 is present it will react with yeast producing CO2 andH2O.

The industrial production of ethanol from sugar cane involves various steps as following:

1)    fermentation

--sugar cane is harvested then crushed and mashed to form sucrose juice (sugar pulp).

--Sugar pulp is heated to 100   C forming sucrose molassc.

-- Diluted sulfaric acid is added to kill bacteria.

--This is then placed in an anaerobic fermentation chamber at approximately 25  C with yeast called (Saccharomyces Cerevisiae).This process takes 2 days producing 15% ethanol and 85% water breaking down glucose into ethanol.

 Glucose-------àEthanol + Carbon Dioxide    (in presence of yeast)

C6H1206 (aq) -------à2C2H50H (aq)+2CO2(g)

The above equation shows fermentation of glucose to form ethanol. Although it is only shown in one equation, many stages take place such as reacting with different enzymes and catalyses.

2) Distillation to purify and remove water (97%ethanol)This requires a large amount of energy.

3) Dehydration to remove water (100%ethanol)