The diagram outlines the basic steps of producing ethanol, a type of biofuel.
In general, the process involves physical, chemical, and biological treatments to produce ethanol from trees and plants. Ethanol is then used as an alternative to fossil fuels to reduce pollution.
At the beginning of the six-stage process, plants and trees absorb carbon dioxide and sunlight from the atmosphere. A process called photosynthesis helps convert these two ingredients into energy, which directly contributes to the growth of these plants and trees. As they reach maturity, people harvest them using machinery. The harvested products will undergo a pre-processing process, which breaks them down into strands of cellulose by crushing. With the help of chemicals, these cellulose strands are further deconstructed into different sugar molecules.
After the aforementioned physical and chemical treatment steps, these sugar molecules are then biologically processed. Microbes are added to convert the sugars into ethanol, which in turn is used as a fuel to power vehicles with combustion engines such as cars, trucks, and planes. These vehicles burn up the ethanol, releasing carbon dioxide as waste into the atmosphere. The trees and plants, in turn, consume this as their food, and the cycle restarts.