A catalyst loses its activity due to__________________?
Correct answer: D. All A., B. and C.
- A. Loss in surface area of the active component
- B. Agglomeration of metal particles caused by thermal sintering of the solid surface
- C. Covering of the catalytic active sites by a foreign substance
- D. All A., B. and C.
Explanation
Catalyst deactivation can result from loss of active surface area, thermal sintering or agglomeration of metal particles, and poisoning by foreign substances covering active sites. Therefore, all three listed mechanisms contribute to activity loss.
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