c) An oil containing 2.55 mol% of a hydrocarbon is stripped by using steam in a countercurrent stripping tower. The flow rate of solvent is 4 kmol of steam for every 100 kmol of oil. The vapour-liquid relationship of the hydrocarbon in the oil is given by y*=50x, where y* is the mole fraction in the vapour and x is the mole fraction in the liquid. The temperature is maintained constant by internal heating, so that the steam does not condense in the tower. The solvent feed contains only steam and no traces of hydrocarbon. By assuming the oil is non-volatile, determine the operating line and equilibrium line required to reduce the hydrocarbon concentration to 0.05 mol%. Plot both lines and attach the plotted graph to the answer script. (10 marks) d) With the help of sketch diagram, differentiate between Linear, Langmuir and Freundlich isotherm in adsorption process