Which abiogenic or biogenic petroleum origin theory fails to account for nitrogen and sulfur compounds in crude oil?
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Answer: B. Carbide theory
Explanation
The carbide theory of abiogenic petroleum origin proposes that metal carbides react with water. This deep underground reaction forms simple hydrocarbons without accounting for nitrogen and sulfur. Natural crude oils consistently contain nitrogen and sulfur heteroatoms that disprove pure carbide origin. Abiogenic theories suggest petroleum forms from inorganic chemical reactions deep within the Earth. Metal carbides underground could theoretically generate acetylene and methane when exposed to water. Biogenic theories like the Engler theory explain heteroatoms through the decomposition of organic matter.
Understanding petroleum origin theories helps geologists model hydrocarbon generation and basin evolution. The presence of biomarkers and heteroatoms strongly supports the biogenic origin of crude oil. Refinery processing design must account for heteroatoms originating from ancient biological precursors. Option A modern theory incorporates abiogenic concepts but generally acknowledges organic inputs. Option C Engler theory is a biogenic model that successfully accounts for nitrogen and sulfur compounds. Option D is incorrect because only the carbide theory fails to explain heteroatom presence.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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