A reversible, endothermic, liquid-phase reaction is conducted in a plug flow reactor. To minimize reactor volume, the temperature profile along the length should be operated such that ?
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Answer: C. Is at the highest allowable temperature throughout
Explanation
Endothermic reactions absorb heat, so higher temperatures shift equilibrium toward product formation. Reaction rates also increase exponentially with temperature according to the Arrhenius relationship. Operating at the highest allowable temperature maximizes both kinetic rates and equilibrium conversion. Le Chatelier principle dictates that endothermic systems favor products at elevated temperatures. Plug flow reactors allow temperature profile tailoring along the reactor length. Material construction limits and thermal stability dictate the maximum allowable operating temperature.
Steam reforming of methane is a highly endothermic reaction requiring high furnace temperatures. Industrial reactors processing endothermic reactions integrate external heat exchangers along the tubes. Optimizing temperature profiles maximizes reactant conversion while protecting reactor materials. Decreasing temperature would lower reaction rates and reduce equilibrium conversions. Varying temperature profiles would fail to maintain maximum possible reaction rates throughout. Maintaining the highest allowable temperature consistently optimizes endothermic reactor performance.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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