Ethanol was oxidized to acetic acid in a catalyst chamber at . What should be rate of removal of hea — Thermodynamics and Thermochemistry Chemistry Question
Question
Ethanol was oxidized to acetic acid in a catalyst chamber at $18^\circ\text{C}$. What should be rate of removal of heat (in kcal/hr) to maintain the reaction chamber at $18^\circ\text{C}$ with the feed rate of 2.3 kg ethanol per hour, along with excess oxygen to the system at $18^\circ\text{C}$, with a 40 mole per cent yield based on ethanol. The enthalpies of formation of $\text{H}_2\text{O(l)}$, $\text{C}_2\text{H}_5\text{OH(l)}$ and $\text{CH}_3\text{COOH(l)}$ are, respectively, –68, –66 and –118 kcal/mol.
💡 Solution & Explanation
Reaction: $\text{C}_2\text{H}_5\text{OH(l)} + \text{O}_2\text{(g)} \to \text{CH}_3\text{COOH(l)} + \text{H}_2\text{O(l)}$. $\Delta H_{\text{rxn}} = -118 - 68 - (-66) = -120\text{ kcal/mol}$. Feed rate of ethanol = $2300\text{ g/hr} / 46\text{ g/mol} = 50\text{ moles/hr}$. Moles reacting (40% yield) = $50 \times 0.40 = 20\text{ moles/hr}$. Heat removal rate = $20\text{ mol/hr} \times 120\text{ kcal/mol} = 2400\text{ kcal/hr}$.