A distillation column at 101 kPa is used to separate 350 kmol/h of a bubble point mixture of toluene and benzene into an overhead product with 3 mole % toluene and a bottoms product with 98 mole % toluene. The feed contains 0.45 mole fraction benzene. The overhead reflux occurs at saturation temperature (implies it is total condenser – if it was not, you would have a vapor liquid mixture or a partial condenser akin to a partial reboiler). VLE data for the mixture is given below. An average alpha can be found from the VLE data if solving analytically. EQUILIBRIUM DATA IN MOLE- FRACTION BENZENE, 101 kPA
y 0.21 0.37 0.51 0.64 0.72 0.79 0.86 0.91 0.96 0.98
x 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 0.95

Required:
a. What are the distillate and bottoms flow rates (D and B)?
b. What is the minimum reflux ratio, Rmin (corresponding to N= infinity)?

A3-mm-thick panel of aluminum alloy (k 177 w/m-k, c 875 j/kg-k and ? = 2770 kg/m) is finished on both sides with an epoxy coating that must be cured at or above t,-150°c for at least 5 min. the production line for the curing operation involves two steps: (1) heating in a large oven with air at ts,0-175°c and a convection coefficient of h, 40 w/m2. k, and (2) cooling in a large chamber with air at 25°c and a con- vection coefficient of he 10 w/m2.k. the heating portion of the process is conducted over a time interval te which exceeds the ime required to reach 150°c by 5 min (h = r + 300 s). the coating has an emissivity of ? = 0.8, and the temperatures of the oven and chamber walls are 175 and 25°c, respectively. if the panel is placed in the oven at an initial temperature of 25°c and removed from the chamber at a safe-to-touch tempera ture of 37°c, what is the total elapsed time for the two-step curing operation?