For an isothermal, zero-order irreversible reaction A → B, the fractional conversion of A in a CSTR is 0.3 at a space velocity of 0.1 min-1. Determine the conversion for a PFR operating at a space velocity of 0.2 min-1, assuming all other conditions remain constant?
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Answer: C. 0.60
Explanation
Zero-order reaction rates are independent of reactant concentration throughout the system. Plug flow reactor conversion is calculated directly from the rate constant and space velocity. Doubling space velocity while maintaining zero-order kinetics doubles the resulting fractional conversion. Space velocity is the reciprocal of space time, representing reactor volumes fed per unit time. Zero-order reactions proceed at constant rates until limiting reactants are fully depleted. Continuous stirred tank reactors and plug flow reactors have different performance equations.
Zero-order kinetics simplify reactor scaling calculations between continuous stirred tanks and tubular units. Industrial photocatalytic reactors often operate under zero-order reaction rate regimes. Comparing reactor types helps optimize capital and operating costs for chemical plants. Zero point fifteen underestimates conversion by incorrectly reducing it with higher velocity. Zero point thirty assumes conversion remains unchanged despite altered space velocity. Zero point ninety overestimates the maximum possible conversion for this operating condition.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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