Which of the Following Is Not a "Clean Coal" Technology

question 4

Multiple Choice

Which of the following is not a "clean coal" technology already in use?

• A)"Coal washing" to remove sulfur and other mineral impurities from the coal before it is burned.
• B)"Gasification" to convert coal to a mixture of carbon monoxide and hydrogen.The resulting gas burns at a lower temperature,thus reducing the generation of nitrogen oxides.
• C)"Wet scrubbing" to chemically remove SO₂ before it goes up the smokestack.This is accomplished by reacting the SO₂ with a mixture of ground limestone and water.
• D)"Sequestration" to capture and store CO₂ before it is emitted into the atmosphere.

---

Definitions:

Aldol Reaction

A chemical reaction between aldehydes or ketones, catalyzed by a base, leading to β-hydroxyaldehydes or β-hydroxyketones.

Crossed-aldol Product

The product resulting from an aldol reaction between two different aldehyde or ketone reactants, occasionally leading to complex mixtures.

2,2-dimethylpropanal

A chemical compound, specifically an aldehyde, characterized by the presence of two methyl groups attached to the second carbon in a propane chain.

Propanal

An organic compound with the formula CH3CH2CHO, a type of aldehyde that is used as an intermediate in organic synthesis.