2 replies to this topic

[Sadananda Konchady]

Wet scrubbers are routinely used to recover ethanol in the CO2 gas from ethanol fermentation vessels.

Can scrubbing with Sodium Sulfite solution instead of just water help in reducing acetaldehyde emission
in the vent gas from the wet scrubber?

What would be the chemical reactions?

One weblink suggesting the use of sodium sulfite scrubbing is at:

http://www.hawkrenew...ion_process.asp



Escape

[sgkim]

Escape:

The wet scrubber seems to absorb ethanol and other volatile organic compounds including acetaldehyde. If Sudium sulfite solution is used acetaldehyde may be reduced to ethanol in the scrubber as the following reaction:

CH3CHO + Na2SO3 + H2O ---> C2H5OH + Na2SO4

Since the sodium sulfite acts as a strong reducing agent, the other aldehydes or acids can also be reduced to corresponding alcohols by the similar reaction like the above. But you must consider a suitable method for the treatment of sodiun sulfate solution accumulating in the scrubbing water circulating.

Stefano

[pawan]

if concentration is good enough U can use Genosorb in place of any chemical absorbent. This will give u low cost recovery of lost Ethanol.