Question 96 from UPSC CSE 2025 - Environme nt & Ecology

Question

Consider the following substances:
1. Ethanol
2. Nitroglycerine
3. Urea
Coal gasification technology can be used in the production of how many of them?

IASCODEX · Accepted Answer

Correct Option: B. Only two

Strategy: For this question, focus on how syngas from coal gasification is used as a chemical feedstock. Ethanol and urea can both be synthesized using carbon monoxide and hydrogen derived from syngas, via industrial bioprocess or chemical synthesis. Nitroglycerine, on the other hand, is made by nitrating glycerol, not via pathways associated with coal gasification or syngas. Thus, only two out of the three—ethanol and urea—can be directly produced from coal gasification technology.

Key Info: Coal gasification is the process of converting coal into synthesis gas (syngas), mainly a mixture of carbon monoxide and hydrogen. This syngas serves as a precursor in several industrial processes:

- Ethanol: Syngas can be biologically fermented or chemically catalyzed to produce ethanol. Modern technologies enable the use of gasified coal to create bioethanol as an alternative fuel. India's research and industrial sectors have demonstrated syngas-to-ethanol production.
- Urea: Urea fertilizer production involves synthesizing ammonia, which is typically obtained by combining hydrogen (from syngas or natural gas reforming) with atmospheric nitrogen (via Haber-Bosch process), followed by conversion with carbon dioxide to form urea. Coal gasification-based ammonia-urea complexes, such as the Talcher Fertilizer plant in Odisha, explicitly utilize syngas from coal.
- Nitroglycerine: This compound is synthesized by nitrating glycerol using a mixture of concentrated sulfuric and nitric acids. Glycerol itself is typically a by-product from processes like saponification (soap-making) or biodiesel production, not a coal-derived substance. Syngas plays no role in nitroglycerine manufacture.

Coal gasification thus enables the production of ethanol and urea using coal as the input, but not nitroglycerine. This distinction is relevant in the context of industrial chemistry and energy-fertilizer integration policies.

IASCODEX · Answer

Option A: Only one

IASCODEX · Answer

Option C: All three

IASCODEX · Answer

Option D: None

Consider the following substances: Ethanol Nitroglycerine Urea Coal gasification technology can be used in the production of how many of them?

Consider the following substances:

Ethanol

Nitroglycerine

Urea
Coal gasification technology can be used in the production of how many of them?