[rtrt228]

I am passing pure Nitrogen gas at 60 cm3/min through 99.9% pure Methanol. I want to calculate how much volume % of methanol is there in the exit stream? The temperature is 27 degC, and at atm pressure.  The total mass loss of Ch3OH is 8.2 gm if I pass the gas, through it, for 8 hrs.

I can calculate that the total volume loss of Ch3OH (due to the gas stream) is 10.39 cm3 using density of methanol.

Your help will be appreciated.

Thank you.

[gensuruthebomber]

If the process is asumed continuum you can calculate the average flow of methanol as (8,2 [g]) / (8*60 [min]*32 [g/mol])=5,338 *10^-4 [mol /min], the flow of nitrogen is (0,060 [l/min]*1 [atm])/(0,0821 [atm l /mol K]*(27+273,15)[K])=2,4348 *10^-3 [mol]

Now you can calculate the molar fraction leaving:

Y (CH3OH)= 5,338*10^-4 / ( 5,338*10^-4+2,4348*10^-3)=0,1798 [-]

Maybe I wrong the numbers, but keep the idea.

[discodermolide]

I am passing pure Nitrogen gas at 60 cm3/min through 99.9% pure Methanol. I want to calculate how much volume % of methanol is there in the exit stream? The temperature is 27 degC, and at atm pressure.  The total mass loss of Ch3OH is 8.2 gm if I pass the gas, through it, for 8 hrs.

I can calculate that the total volume loss of Ch3OH (due to the gas stream) is 10.39 cm3 using density of methanol.

Your help will be appreciated.

Thank you.

Perhaps you can clarify something for me?
You say the total mass loss of methanol is 8.2 g after 8 hours at 60 cm³ N₂/minute! That is a tremendous flow of gas with not much methanol loss.
Then in the next sentence you say that the total volume loss of methanol is 10.39 cm³.
This can't be right, 8.2g and 10.39 cm³.

[DrCMS]

Perhaps you can clarify something for me?
You say the total mass loss of methanol is 8.2 g after 8 hours at 60 cm³ N₂/minute! That is a tremendous flow of gas with not much methanol loss.

I agree i would expect a much bigger loss from that flow rate for 8hrs.

Then in the next sentence you say that the total volume loss of methanol is 10.39 cm³.
This can't be right, 8.2g and 10.39 cm³.

That looks right to me density of liquid methanol is ~0.79g/ml.

[discodermolide]

Yes he is saying that the volume loss is 10.39 cubic meters.
If he looses only 8,2g after 8 hours then the volume lost is 8.2/0.79 = 10.39mL .

[AWK]

You can calculate moles of gas at that conditions and moles of methanol.
Since moles of gas are proportional to volumes at the same conditions  then % volume is the next step.

[DrCMS]

Yes he is saying that the volume loss is 10.39 cubic meters.

No he is not; he stated the volume lost was 10.39 cubic centimetres.

[discodermolide]

I beg your pardon, I mis-read this. Please accept my apologies.

[DrCMS]

I beg your pardon, I mis-read this. Please accept my apologies.

No problem, everyone makes mistakes from time to time.  Honest people own up to them and move on; fools try to hide them and dig themselves a really big hole to fall into in the process.

[Borek]

"If a honest man is wrong, after demonstrating that he is wrong, he either stops being wrong or he stops being honest."