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pH adjustment of C5 liquid.

pH adjustment of C5 liquid.

pH adjustment of C5 liquid.

(OP)
Hi folks,
I am adjusting the pH of liquid solution (containng C5 liquid) by adding NaOH. Sodium sulphate will formed.
Can I assume the reaction to be 100% complete at 70 C?
Is Sodium sulphate soluble in liquid fration?
This stream is then mixed with C6 (solid fraction)before distillation and then separated to liquid and solid fration.
My concern is in which stream (Liquid or solid) this sodium sulphate formed will end up.
Since the solid fraction is supposed to use in the boiler, if sodium sulphate end up in this stream then there will be problem in boiler (scaling up on the boiler tubes, poor heat transfer) and additionally will have to pay Sulphur taxes the for the sulphur contents in the exhast gases.
Could anyone suggest on this.
Thanks in advance for your help on the issue.

RE: pH adjustment of C5 liquid.

zamu2010:

Why do you think that washing pentane (C5 liquid) with NaOH will yield sodium sulfate? Do you believe the pentane has some entrained sulfuric acid? I doubt it.

Why do you think that hexane (C6) is a solid? At atmospheric pressure, hexane's freezing point is -96 degrees C (-140 degrees F). Is your hexane that cold? I also doubt that.

Are you trying to use a mixture of liquid C5 and liquid C6 as fuel to a fired-boiler? Pretty expensive fuel.

Give us more information on what you are trying to do.

Milton Beychok
(Visit me at www.air-dispersion.com)
.

 

RE: pH adjustment of C5 liquid.

(OP)
Hi Mbeychok,
Thank you very much for your reply.
I can see its was a bit hard to follow what I asked. Lets me explain.
We are in R&D phase for Bio-ethanol production from biomass (C5 mainly liquid and C6 solid phase) and sulfuric acid acid in these stream comes from the pre-treatment step and more likely to end up in the liquid stream C5. (C5 and C6 are separated after pre-treatment). We adjust the pH by adding NaoH before both streams are sent to Distillation to recover Bio-ethanol and down-stream are separted in to the liquid and solid stream again. The solid stream is intended to use in the boiler.
So the issue it where product of neutralization reaction will end-up and how to handle this in the terms of sulfur contents.

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