A solute is absorbed from a vapor stream mixture using a non-volatile liquid. The entering vapor is 2.5 mole % solute, and the entering liquid is solute-free. The solute present in the vapor is 92% absorbed and the concentration of the liquor at the bottom of the tower contains 1.36 mole % solute. Assuming an overall vapor stream flow rate of 60 moles/hr the equilibrium and operating lines for a counter-current separation have already been graphed (This figure is provided for your use / consideration). 0.0300 y, mole fraction 0.0250 0.0200 0.0150 0.0100 0.0050 0.0000 0.0000 0.0050 0.0100 0.0150 0.0200 0.0250 0.0300 x, mole fraction Based on the information available a basic and any calculations deemed necessary: 1. What is the minimum number of equilibrium stages necessary to achieve the desired separation? (Based on a graphical solution) 2. What is the inlet liquid flowrate for this column (the operation shown; moles/hour)? 3. What is your estimate for the thermodynamic partition coefficient that describes the solute equilibrium in this system? Be clear in your math/explanation.

Benzene is to be absorbed from coal gas by means of a wash-oil. The inlet gas contains 3 per cent by volume of benzene, and the exit gas should not contain more than 0.02 per cent benzene by volume. The suggested oil circulation rate is 480 kg oil/100 m³ of inlet gas measured at 273 K and 101.3 kN/m². The wash oil enters the tower solute-free. If the overall height of a transfer unit based on the gas phase is 1.4 m, determine the minimum height of the tower which is required to carry out the absorption. The equilibrium data are: Benzene in oil (per cent by mass) Equilibrium partial pressure of benzene in gas (kN/m²) 0.05 0.013 0.01 0.033 0.50 0.20 1.0 0.53 2.0 1.33 3.0 3.33

In a counter-current absorption tower, a process gas containing 0.04 (mole fraction) ammonia is scrubbed with pure water. The exit gas contains 0.002 (mole fraction) ammonia.The diameter of the tower is 1m, and the packing has a large area per volume of 200 m2m–3. The overall mass transfer coefficient based on the liquid side driving force, KL, is 1.5×10−5ms–1. The total gas and liquid concentrations are 0.6kmolm–3and 20 kmolm–3respectively and the gas flowrateis 0.03kmols–1. The actual liquid to gas ratio is 1.5 times that of the minimum liquid to gas ratio. The equilibrium for ammonia between the air and water is given by y* = 1.04x. What is the mol fraction of ammonia in the liquid?

1) An evaporator is concentrating solutions coming from three different sources.The first source contains 20% NaCl by weight, the rest is water. The secondsource contains 10% by weight NaCl, 30% NaOH by weight, the rest water. Thethird source contains 25% NaCl by mole, 25 % NaOH by mole, the rest water.The feed streams are fed directly to the evaporator at the following flow rates;100 kg/min for the first source, 7800 kg/min for the second source and 120kg/min for the third source. If 70% of the original water is evaporated, calculate(a) composition in % by weight of the product (b) the flow rate in kg/min of theproduct.2) Two process streams are mixed to form a single stream. Only the flow in themixed stream is known. A soluble salt is added to one of the original streams ata steady rate. Samples taken of this stream show it to be 4.76 % w salt. Samplesfrom the combined stream show 0.62% w salt. What is the ratio of the flows inthe two original streams?3) A chemist attempts to prepare…

A cooling tower works with the amount of cooling water 1 ton/hour. Conditions of cooling water in the cooling tower has a solid content of 1350 ppm. The cooling water entering the cooling tower is processed in such a way that the solids content is a maximum of 225 ppm. If the cooling water evaporated rate is assumed to be 2.5% the cooling water inlet rate, calculate the concentration cycle, the added water rate, and the blowdown water rate!

A reverse-osmosis unit is used to obtain pure water from saline water. The coefficient of water permeation is 0.1 mol/cm2 s atm. The pressure differential across the membrane is 0.2 atm, and the osmotic pressure differential is 0.05 atm. The water flux across the membrane is most nearly (A) 0.0050 mol/cm2·s (B) 0.015 mol/cm2·s (C) 0.050 mol/cm2·s (D) 0.15 mol/cm² ·s

A stream containing propionic acid and water at 60:40 mass ratio is fed to a mixer at 3 kg/s with pure cyclohexane as solvent. What should be the flow rate of the solvent in order to attain 40:60 mass ratio of solute and solvent in the extract (solvent-rich) stream? Prepare graphical and computational solution.

You are working on determining the Oxygen Transfer Rate (OTR) and Oxygen Uptake Rate (OUR) in a bioreactor.  You perform two set of experiments in a 3L bioreactor.  During the first set of experiments, you fill the bioreactor with water only, you remove all the dissolved oxygen and start sparging it with air at the specified agitation speeds and air flowrate.  Which of the following methods could be used to estimate the volumetric oxygen transfer coefficient (kLa)? C*: saturation concentration of dissolved Oxygen  CL: concentration of dissolved Oxygen at any given time   Question options:   kLa  is the slope of a ln(C* ) versus time plot   kLa  is the slope of a CL versus time plot   -kLa  is the slope of a ln(C* - CL) versus time plot   kLa  is the slope of a ln(C* - CL) versus time plot

A water cleanup operation involves stripping vinyl chloride from contaminated ground water at 25 °C and 850 mm. Hg using a countercurrent, staged stripper. The feed has 5.0 ppm(molar) vinyl chloride, and the outlet water contains 0.1 ppm (molar) vinyl chloride. Inlet air used for stripping is pure. For a liquid flow rate of L = 1 kmol/h , determine the following :  Minimum gas flow rate in kmol/h. If the actual gas flow rate = 2.0 × (minimum gas flow rate) calculate the number of stages Henry’s constant (HB) for vinyl chloride = 1243. 84 atm.

1. [25] The diffusion of the gas phase A through a layer follows the equation at dz² Solve the differential equation either by the variable combination method variable separation or Laplace transform, Choose a method that you understand, if you know the initial conditions and boundary conditions are as follows: C (z, 0) = Co C (0, t) = Cs C (0, t) = 0