Chemistry Alcohols & Phenols NUMS 2019
PMDC Verified Question 68 of 95
Industrially water gas is converted into methanol by using catalyst
A
\(\text{CuO} + \text{ZnO}\)
B
\(\text{CuO} + \text{Cr}_2\text{O}_3\)
C
\(\text{Al}_2\text{O}_3 + \text{ZnO}\)
D
\(\text{ZnO} + \text{Cr}_2\text{O}_3\)
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option D: \(\text{ZnO} + \text{Cr}_2\text{O}_3\)
Concept:

The industrial synthesis of methanol from syngas/water gas (\(\text{CO} + \text{H}_2\)) requires high temperature, high pressure, and a specific mixed-oxide catalyst to proceed efficiently.

Formula:

$$ \text{CO} + 2\text{H}_2 \xrightarrow[400^{\circ}\text{C, 200 atm}]{\text{ZnO/Cr}_2\text{O}_3} \text{CH}_3\text{OH} $$

Solution:

  • The standard catalytic mixture utilized historically and conceptually in this curriculum is zinc oxide (\(\text{ZnO}\)) promoted by chromium(III) oxide (\(\text{Cr}_2\text{O}_3\)).


Why other options are incorrect:

The combinations in A, B, and C lack the specific synergistic interaction of the \(\text{ZnO} - \text{Cr}_2\text{O}_3\) system required to lower the activation energy for this specific carbon monoxide reduction.

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