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Convert MOLAR% to VOLUME %

Convert MOLAR% to VOLUME %

Convert MOLAR% to VOLUME %

(OP)
I look how to convert molar % to volume %!

I have gas mixture at pressure 80bar/1160psia and temperature 47 C (calsiouse)/320,15K

IT IS CONSTIST OF:

methane 8.99% molar
ethane 1.21% molar
propane 1.04% molar
butane 0.60% molar
penthane 0.23% molar
hexan 0.16% molar
heptan 0.06% molar
octan 0.01% molar
CO2 84.22% molar
H2O 3.39% molar
N2 0.02% molar
H2S  0.007% molar

I NEED TO CONVERT THIS TO CONVERT THIS STREAM TO VOLUME %!

THAT IS IT .... THANKS ...THANKS AND THANKS IN ADVANCE

MARKO

RE: Convert MOLAR% to VOLUME %

If the ideal gas law can apply to all components at the given temperature & pressure, the solution is trivial: Mole fraction = volume fraction.

If not, evaluate each component at the given temperature & pressure.
Start with 1 mole of mixture, then for example, methane:

if the ideal gas law applies:
Volume (.0899 mol methane) = volume from gas law.

if not:
Volume (.0899 mol methane) = volume based on table or equation.

Add up all the volumes, then

volume fraction (methane) = volume (methane)/volume (of all components)

Seems right, but don't blow something up on my say it is so.

RE: Convert MOLAR% to VOLUME %

(OP)
Hello moon 161, thank s this time on interesting in my problem.

BIG THANKS!

Well how my gas mixture is deffinitly not ideal i must look for your second option!

How ever my biggest problem is exactly there....

you said "Volume (.0899 mol methane) = volume based on table or equation." .... exactly is that what i don t have idea! : (

what tables and what equals (equals of state????)
even i heard somewhere that i need the factorr of compresibilty (z) for each component!

THANK S ONE MORE TIME IN ADVANCE FOR AMY KIND OF HELP!!!

MARKO

RE: Convert MOLAR% to VOLUME %

(OP)
No it s not.

RE: Convert MOLAR% to VOLUME %

Then, how is it that an engineer does not understand:
"Volume (.0899 mol methane) = volume based on table or equation." ....  

TTFN
FAQ731-376: Eng-Tips.com Forum Policies

RE: Convert MOLAR% to VOLUME %

(OP)
Ok .... as i understud 0.0899 molar% is same as 0.0899 volume%?

Maybe you wanted to say something else?

I wound some interesting lint about this ....but it make me wrong result .... http://www.dcgpartnership.com/Docs/Conversions/Mole_to_Wt_to_LV.pdf

PS- english is not my mother language ...

THANKS to everybody!

MARKO

 

RE: Convert MOLAR% to VOLUME %

OK.

Start w/ one mole total. You then start with:
mol fraction * 1 mol of each species-

.0899 mol methane,
.0121 mol ethane, and so on, down the list.

Make sure it all ads up to 1.00 mol.


For each species, methane, CO2, whatever, determine the volume per mole at the given state, 80 bar, 320K. If this state is well away from the vapor dome for the species, you can just use the ideal gas law, PV=NRT. keep your R's straight, there are a few forms of the gas law used and KEEP YOUR UNITS STRAIGHT! As a check, calculate the volume of 1 mole of gas at 1 bar, 273K, should be 22.4 liter:

http://en.wikipedia.org/wiki/Ideal_gas_law

Otherwise, if you are near the vapor dome, you'll need to use a table or chart to find the properties at your state, 80 bar, 320k.

The volume of each species will be:
mole fraction * volume per mole.

Add up all the volumes. If you come out w/ .32 liter, using the ideal gas law would have been fine.

The volume fraction of each species will then be the volume the species, divided by the total of all of the volumes.

Warning: I design air conditioners & sheet metal, not refineries. Use the above as a guide as you sit down with your chemistry book.
 

RE: Convert MOLAR% to VOLUME %

(OP)
OK ....THANKS ... I WILL TRY TO MAKE SOMETHING WHIT THIS IDEA!

ONE MORE TIME THANKS ....

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