Question

002 The preliminary experimental result of th temperature of respectively. The DAB value obtained from the experiment was 0.1429 cm'ls. e diffusion coefficients, DAB for gas carbon dioxide (CO,) in oxygen(e) was measured using large lateral shearing interferometric system at 35° Cand atmospheric pressure. The test was conducted in diffusion cell which is attached in the system with dinension of 0.01 m and 100 em for diameter and tube long. By using Chapman and Enskog Method, predict the value of DAB for the binary gas mixture at 35°C. Discuss the accuracy of the result obtained by prediction experiment. (14 Marks) nd DA b) The experimental system is suitable for the measurement of the gas diffusion coefficients aluc P by under high pressures. At steady state conditi is increase from 35 C to 55 °C and 1 atm to 10 atm respectively i) Caiculate the flux for CO e temperature and pressure condition I:75 CA i) Caiculate the fhux for Co gas, in kg.mol/s.n? if the partial pressure at point I is 200 kPa and 116.325 kPa at the other point. Assume both gases are permeable in an uniform tube and the flux is equimolar counter diffusion. The diffusivity can be calculated by temperature corrected factor based on Fuller et al Method. (7 Marks) ii) Estimate the partial pressure of CO2 at the middle of the experimental system from point 1 by using data provided in b(i). (4 Marks) i) If the CO2 gas in the system is replaced by methane (CH), which molecules will diffuse faster in O2? Justify your answer. (5 Marks)

Answer 1

a) ans: A= Co₂=M_a=44 B=O₂= 32

Lennar ou patameter 1k. kT- 308 - 二小612- Ens 190.qr AD = 0,806. tlen ken by chabman Esk meod 1. Г 44 ,3 0,240 cm Hence, ha expanow ent- d we tove obtained phek ゾ。

T=35= 35+273=308K

P_r= 1 atm

b) ans:
(200 PA -314 X328xo.r 41. 4
b. iii) ans:

CH₄ will diffuse faster because diffusivity is inversely proportional to the molecular weight. molecular weight of the methane is less than the carbon dioxide. so diffusivity will be more than the carbon dioxide.