Previous Year Question
Consider the following statements.
Statement I: Of the two major ethanol producers in the world, i.e., Brazil and the United States of America, the former produces more ethanol than the latter.
Statement II: Unlike in the United States of America where corn is the principal feedstock for ethanol production, sugarcane is the principal feedstock for ethanol production in Brazil.
Which one of the following is correct in respect of the above statements?
Both Statement I and Statement II are correct and Statement II explains Statement I
Both Statement I and Statement II are correct, but Statement II does not explain Statement I
Statement I is correct, but Statement II is not correct
Statement I is not correct, but Statement II is correct
Correct Answer: D
Detailed Solution
The United States is the world’s largest producer of ethanol, while Brazil is the second major producer.
Therefore, it is not correct to state that Brazil produces more ethanol than the United States. Hence, Statement I is not correct.
In the United States, corn is the principal raw material used for the production of fuel ethanol.
The starch present in corn is first converted into sugars and then fermented to produce ethanol.
Corn-based ethanol production also yields co-products such as distillers dried grains, which are used as animal feed.
In Brazil, sugarcane is the principal raw material used for ethanol production.
The sugars present in sugarcane juice can be directly fermented to produce ethanol.
Therefore, Statement II concerning corn-based production in the United States and sugarcane-based production in Brazil is correct.
Bagasse obtained from sugarcane can be used to generate heat and electricity in ethanol plants.
In the United States, ethanol is mainly used as a blend with gasoline.
In Brazil, flex-fuel vehicles capable of using gasoline-ethanol blends as well as pure hydrous ethanol are also widely used.
Ethanol produced from corn and sugarcane is regarded as a first-generation biofuel.
Ethanol produced from agricultural residues and other lignocellulosic materials is called second-generation ethanol.
Ethanol can reduce petroleum consumption and certain pollutants, but its overall environmental benefits depend upon the crop, land use, water, energy and production method.