A continuous distillation column is used to separate an equimolar mixture of diethylamine (DEA) and methanol. The feed enters the column as saturated liquid at a flow rate of $30 \mathrm{~mol} \mathrm{~s}^{-1}$. It is desired to obtain $92 \mathrm{~mol} \%$ DEA as distillate. The rate of withdrawal of the distillate from the column is $10 \mathrm{~mol} \mathrm{~s}^{-1}$. The equilibrium curve for the conditions in the column is given below. The latent heat of vaporization of the reboiler contents is $35 \mathrm{~kJ} \mathrm{~mol}^{-1}$. Neglect heat loss to the surroundings and assume constant molal overflow. Which one of the following is the minimum reboiler heat duty (in kW)?
- $350$
- $700$
- $1120$
- $1470$
