7 replies to this topic

[S.R.Shah]

Dear All,

Recently I have have came across design problem to concentrate Dilute hydrochloric acid solution of 4 % HCl.

I have gone through Partial Pressure Tables from Parry to design via evaporation route-Continuous .But the partial pressure of Hydrogen Chloride is very low.

Please guide me for
1. Maximum Concentration possible
2.If any other method than evaporation-Boiling available.
3. Hints-Steps to get concentration at least up to 21% Azeotropic Mixture

I have searched through Google-Scirus but not got any clue for designing for 21% concentration or more .

Thank you in Advance.

Samir

[breizh]

Hi ,
let you try this resource

http://www.cheresour...dpost&pid=45595


Breizh

[S.R.Shah]

Hi ,
let you try this resource

http://www.cheresour...dpost&pid=45595


Breizh

Dear Breizh,

As the 4 % HCl shall boil ,referring to Partial Pressure data; Water vapor shall rise with Hydrochloric acid vapors, If I shall Install condenser Above the Packed Bed,HCl get may became soluble in condensed water,which may produce again dilute Acid.

Can you please elaborate on behavior of 4%Hydrochloric acid boiling or process of concentration.

Regards

Samir

[breizh]

Hi ,
Take a look at this resource :

http://www.qvf.com/e...loricAcid.shtml

BTW is it worth to concentrate a solution @ 4% Hcl ?

21% is the azeotrope !

hope this helps

Breizh

[kkala]

One remark that may be useful concerning enthalpy diagrams of aqueous HCl: I remember Chemical Engineering (Feb 3, 1986) saying that relevant Figure 3-27 of Perry 5th ed (1973) has following errors.
(1) Enthalpies are in kcal/mol; correct is cal/mol.
(2) Reference state for HCl is erroneous.

Relevant Fig 2-11 of Perry 7th ed (1997) has corrected (1) and has changed (2).

So some care is needed when enthalpy concentration diagrams of aqueous HCl are to be used (from Perry or others, having taken data from Perry).

[S.R.Shah]

Hi ,
Take a look at this resource :

http://www.qvf.com/e...loricAcid.shtml

BTW is it worth to concentrate a solution @ 4% Hcl ?

21% is the azeotrope !

hope this helps

Breizh

Dear Breizh,

I have gone through the article but for Concentration above Azeotropic Concentration.

In the same article ;it is written that ''If the acid concentration is lower than the azeotrope mixture, the acid can be concentrated only up to the azeotropic point''.

My further question is that if dilute acid is boiled , Concentrated Acid Shall come from top or bottom of Distillation Column.It is tricky .I have searched through internet and found one interesting article.In said technology, Vaporised HCl + H2O vapor fed in between Enriching and stripping section.Concentrated HCl -8% shall taken out from bottom of the column.As this process is designed to remove iron particles and final concentration is only 8% this may not work for me as I need Concentration upto 21%.

Please find attached the same.

If I shall come to certain conclusion,I shall Let you know.

Please Help

Regards

Samir

Attached Files

•  ESL-IE-94-04-02.pdf   2.63MB   90 downloads

[S.R.Shah]

One remark that may be useful concerning enthalpy diagrams of aqueous HCl: I remember Chemical Engineering (Feb 3, 1986) saying that relevant Figure 3-27 of Perry 5th ed (1973) has following errors.
(1) Enthalpies are in kcal/mol; correct is cal/mol.
(2) Reference state for HCl is erroneous.

Relevant Fig 2-11 of Perry 7th ed (1997) has corrected (1) and has changed (2).

So some care is needed when enthalpy concentration diagrams of aqueous HCl are to be used (from Perry or others, having taken data from Perry).

Hi Mr. Kkala,
Thank you for reply.Please also go through My reply to Breizh and advise.

Samir

[breizh]

Hi Samir ,

More info available:


http://www.betacontr...very-literature

You may contact them
Hope this helps

Breizh