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Specialty Chemistry Forums => Chemical Engineering Forum => Topic started by: metallurgy on February 03, 2020, 06:13:30 AM

Title: How to reproduce NaHCO3 by using Sodium Sulphate?
Post by: metallurgy on February 03, 2020, 06:13:30 AM
In an industrial SO2 filter (https://backend.orbit.dtu.dk/ws/portalfiles/portal/6226780/Stig.pdf) most probably this reaction occurs:

2NaHCO3 + SO2 + 1/2 O2 :rarrow: Na2SO4 + 2CO2 + H2O
(https://www.tandfonline.com/doi/pdf/10.1080/00022470.1984.10465793)

And this above reaction generates lots of sodium sulphate as a waste material.

So, is there any way to reverse engineering can be done?  Can we react sodium sulphate with some material and produce NaHCo3 again and inject the system ? Can this be automate in an industrial level like recirculation of the method? (Like generating sodium sulphate then converting into nahco3 and then sodium sulphate again... )

Title: Re: How to reproduce NaHCO3 by using Sodium Sulphate?
Post by: chenbeier on February 04, 2020, 04:00:04 AM
If you add calciumhydrogencarbonate. Gypsum will be formed and you have it back.

Na2SO4 + Ca(HCO3)2 => CaSO4 + 2 NaHCO3
Title: Re: How to reproduce NaHCO3 by using Sodium Sulphate?
Post by: metallurgy on February 04, 2020, 04:30:51 AM
If you add calciumhydrogencarbonate. Gypsum will be formed and you have it back.

Na2SO4 + Ca(HCO3)2 => CaSO4 + 2 NaHCO3

Okay, is this can be applied industrial level (large scale) ?
Title: Re: How to reproduce NaHCO3 by using Sodium Sulphate?
Post by: chenbeier on February 04, 2020, 05:46:20 AM
Why not.  But you also can absorb the SO2 directly on calciumcarbonate. No sodium(hydrogen)carbonate necessary.
Title: Re: How to reproduce NaHCO3 by using Sodium Sulphate?
Post by: metallurgy on February 04, 2020, 06:24:11 AM
Why not. 
Ok, so what kind of equipment, machinery and process is that?

maybe this:
(https://image.slidesharecdn.com/nahco3-171119173004/95/nahco3-and-na2co3-manufacturing-by-solvay-process-5-638.jpg)
??

But you also can absorb the SO2 directly on calciumcarbonate. No sodium(hydrogen)carbonate necessary.
Yes but the filter system (MEROS) designed to use Sodiumbicarbonate by default, i don't think that can be variable, or they use it because it absorbs 90%.. So we must think what can we do with its sodium sulphate waste...
Title: Re: How to reproduce NaHCO3 by using Sodium Sulphate?
Post by: chenbeier on February 04, 2020, 07:32:24 AM
This is the solvay process to make sodiumcarbonate from sodiumchloride basically. Nothing to do with Sulphurdioxide.

https://en.wikipedia.org/wiki/Solvay_process
Title: Re: How to reproduce NaHCO3 by using Sodium Sulphate?
Post by: metallurgy on February 04, 2020, 07:53:37 AM
This is the solvay process to make sodiumcarbonate from sodiumchloride basically. Nothing to do with Sulphurdioxide.

https://en.wikipedia.org/wiki/Solvay_process

No i meant: can we use solvay process to produce sodiumbicarbonate from Na2SO4 + Ca(HCO3)2 ?
The Na2SO4 generating by the filter as a waste. So we may add Ca(HCO3)2 into it and for an industrial scale , we may use solvay process for doing this?
Title: Re: How to reproduce NaHCO3 by using Sodium Sulphate?
Post by: chenbeier on February 04, 2020, 08:32:21 AM
Probably, but a problem would be at step 7, what will happen there? Convert that diagramm from NaCl to Na2SO4, what other chemicals will go arround, what are the soloubilities in comparison of the existing process?