Writte a summary of 500 words about the effect of ultrafiltration on the mass-transfer efficiency improvement in a pararell-plate countercurrent dialysis system.

cite the references

Methane gas is diffusing in a straight tube 0.1 m long containing helium at 298 k and a total pressure of 1.01325 x 10^5 Pa. the partial pressure of CH4 is 1.400 x 10^4 Pa at one end and 1.333 x 10^3 at the other end. Helium is insoluble in one boundary, and hence is non diffusing or stagnant. Calculate the flux of methane in kg mol/s m^2

In your own words, explain the functions of the following most frequently used unit operations in chemical engineering processes. (i) dryer, (ii) filter, (iii) distillation columns, (iv) absorber, (v) stripper, (vii) crystallizer, (viii) compressor, (ix) valve, (x) hydrocyclone

Saturated steam at a gauge pressure of 0.50 bar is to be used to heat a stream of ethane.

The ethane enters a heat exchanger at 16°C and 1.5 bar gauge pressure at a rate of 795 m³/min and is heated at constant pressure to 93°C.

The steam condenses and leaves the exchanger as a liquid at 20.0°C.

The specific enthalpy of ethane at the given pressure is 941 kJ/kg at 16°C and 1073 kJ/kg at 93°C.

You may take the compressibility factor for ethane to be 0.970 at the inlet conditions.

a) How much power must be transferred to the ethane to heat it from 16°C to 93°C? (kW)
b) At what rate must steam be supplied to the heat exchanger if all the energy transferred from the steam goes to heat the ethane?? (m^3/s)

For part A, I calculated 5490 kW but the answer was incorrect and it gave me this hint ---> "You can calculate the specific enthalpy change by subtraction. Use ideal-gas behavior to calculate the mass of ethane. Carry sufficient significant figures throughout calculation." I used those steps to redo the problem but I continue to get my original answer. Any help would be appreciated.

What is a phase diagram? In a couple of paragraphs, explain what importance phase diagrams are especially when considering eutectic binary metal mixtures? (Hint: https://www.youtube.com/watch?v=h5dwpTqacqc )?

a) Draw a schematic of binary distillation column and annotate it appropriately to include feed, distillate and bottoms flowrates and compositions, equilibrium stages, feed stage, reboiler stage and reflux ratio.

b) State the vapour and liquid compositions entering and leaving the feed stage.

Steam at 361 kPa and 150°C is condensed at its saturation temperature. What is the temperature of the condensate? How much energy is produced by the process?

1. We define the activity of pure liquids as 1 to define the standard state. However, this is an arbitrary choice. Find the dissociation constant, K, for the autoprotolysis of pure water using the molarity standard state for water (i.e. defining the activity as 1 for a water concentration of 1 mol/l). You may take the density of water to be 1.0 g/ml.

2.   Will K have the same value in this standard state at 60?C?   

A high-­viscosity oil is transported through a wide rectangular duct of length L, width W and depth 2B via pressure-­driven flow. The duct is inclined at an angle b? below the horizontal plane (gravity may be assumed to act downwards in the vertical direction), and is sufficiently broad that edge effects may be neglected in the transverse (x2) direction. The pressure at the upstream end of the duct (x1=0) is Po, and at the downstream end (x1=L) is PL. The flow may be regarded as laminar and isothermal, and the oil is a Newtonian liquid;? the duct may be regarded as stationary.

(a) Starting with the appropriate form of the Continuity Equation and Equations of Motion derive an equation for determining the x1 component of velocity at steady state. Be sure to identify all assumptions and boundary conditions. You should attach a marked equation sheet showing the manner in which you simplified the Navier-­ Stokes Equations.

(b) Derive an equation for the volume flow rate of oil through the duct at steady state under these conditions.

(c) Derive an expression for the shear stress T₃₁ at the upper surface of the duct (x3 = B) at steady state.

Collision Theory. Make an outline of the steps that were used to derive

-ra=Ae^(E/RT)CaCb