×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Limiting Oxygen Concentration
2

Limiting Oxygen Concentration

Limiting Oxygen Concentration

(OP)
Does anybody know where to find the LOC of cyclohexane and acrylic acid?
Is it possible to predict the LOC of an organic compound?

Thanks.
Replies continue below

Recommended for you

RE: Limiting Oxygen Concentration

It can be predicted from the stoiciometric oxygen required for complete combustion and the LFL.

Write a balanced oxidation reaction equation to CO2 and H2O.

Example: C3H8 + 5O2 --> 3CO2 + 4H2O

LFL of propane = 2.2% in air

2.2 x 5 = 11.0%

MOC of propane = 11.5% by lab determination.

Good luck,
Latexman

RE: Limiting Oxygen Concentration

I learned it as the Minimum Oxygen Concentration (MOC).  LOC = MOC.

Good luck,
Latexman

RE: Limiting Oxygen Concentration


The minimum concentration of oxygen to propagate a flame by the energy generated in the reaction is the basis for inerting and is called the MOC. Inerting is used to bring the oxygen content to at least 4% points below the MOC.

In the absence of experimental data the procedure explained by Latexman can be used as an estimate that has been confirmed to work for many hydrocarbons.

Published LFL (low flammable limit) values for vapor-air mixtures are generally based on the fuel gas in air at 25oC and 760 mm Hg.

For many organic compounds it was found that the LFL can be approximated by taking 55% of the stoichiometric molar concentration of the fuel in the vapor-air mixture.

Visiting the following threads may add more information:

thread135-73870
thread798-47819
thread816-58335
 

RE: Limiting Oxygen Concentration

As noted in the threads 25362 has referenced, be sure to look at NFPA 69, Standard on Explosion Prevention Systems.  They have listings of LOC for a number of chemicals but unfortunately I did not see cyclohexane and acrylic acid.

I would point out that LOC is affected by the material used as a diluent.  For example, according to NFPA 69 the LOC for propane is 11.5% for a N2/air environment, the LOC for propane is 14.5% for a CO2/air environment.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login



News


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close