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[shilala]

hello everyone, im new here and im glad that i found this site. I am taking up equipment design course now and im assigned to design a packed tower for the removal of unreacted HCl from the product of the deacon process. A 33-36% HCl solution was used to scrub the HCl. The gas stream was composed of chlorine, water, oxygen, nitrogen and other permanent gas from air. Right now i cant proceed with my work because i cant find an equilibrium data or overall mass transfer coefficient for the system. hope that anyone can help me. Do you have any advice of another alternative to use on solving for the minimum L/V ratio and packed tower height without the equilibrium or overall mass transfer coefficient of the system?.... please do help

any advice will be very much appreciated.

[siretb]

Equilibrium Deacon K=(pCl2)(pH2O)/(pHCl)**2/(pO2)**0.5
p are partial pressures atm
Ln(K)=11996/t-0.362LnT +9.36e-4T -2.969e-5T**2 -9.88 T in °K according to Chemical Engineering nov 1998 issue

molal activity coefficient for HCl as reported by Marsh and Mc Elroy 1985
34% wt HCl solution 30°C 25.8; 40°C 21.2; 50°C 17.5
30%wt 30°C 15.2; ; 50°C 11.1

You mention that you scrub with a solution 33-36%. that's seems high (how about 30-32%)? . there is an azeotrope.
As for the mass transfer ou heigth of a transfer unit, I would try to estimate using correlations such as the one developped by Dr Reinhard Billet (Packed towers in processing and environmental technolgy, ISBN 3-527-28616-0
Be cautious of the heating effets. If you have acccess to such tools and want to do the design yourself, process simulators like ASPEN (RATEFRAC) should work fine.
It's diificult to be more specific without knowing the inlet conditions of the gas (T, pressure, and composition)