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GATE 2025 CH – Question 29

Chemical Reaction Engineering · Heterogeneous catalysis, diffusion effects and catalyst deactivation · 1 mark · Multiple choice

Choose the option that correctly matches the items in Group 1 with those in Group 2.

Group 1Group 2
(P) Coking(I) Prolonged exposure of catalyst to high temperature
(Q) Poisoning(II) Deposition of carbonaceous material on catalyst surface
(R) Sintering(III) Irreversible chemisorption of molecules on active sites of catalyst
  1. (P) – (III), (Q) – (I), (R) – (II)
  2. (P) – (II), (Q) – (III), (R) – (I)
  3. (P) – (II), (Q) – (I), (R) – (III)
  4. (P) – (I), (Q) – (III), (R) – (II)

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Correct answer: (B) (P) – (II), (Q) – (III), (R) – (I)

Explanation

Coking is the deposition of carbon (carbonaceous material) on the catalyst surface (II). Poisoning is the irreversible chemisorption of impurities on the active sites (III). Sintering is the loss of surface area through prolonged exposure to high temperature (I). So P-II, Q-III, R-I.