×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

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

auto ignition temperature

auto ignition temperature

auto ignition temperature

(OP)
Is there any relation between auto ignition temperature and C-H ratio?

Many thanks

RE: auto ignition temperature

In a homologous series of organic compounds, the Auto ignition temperature (AIT) decreases with increasing molecular weight. Also a branched compound will have a higher AIT than the corresponding straight-chain compound. There is a plot for straight chain paraffins in one of the NFPA publications. The subject is discussed in Bodurtha's book on Industrial Explosion Prevention and Protection.

HAZOP at www.curryhydrocarbons.ca

RE: auto ignition temperature


The only probable exception to owg's statement is acetylene.

From the net:


AIT = Minimum Autoignition Temperature in oC under test conditions.

                                                   AIT
        n-butane                              370
        n-pentane                            260
        n-hexane                             225
        n-heptane                            225
        n-octane                              220
        n-decane                              210
        n-dodecane                           204
        n-tetradecane                       200

        2-methylpropane                    460
        2-methylbutane                      420
        2-methylpentane                    306
        2,2,3-trimethylbutane              420
        2,2,4-trimethylpentane            415

        cyclopentane                          380
        cyclohexane                            245
        methylcyclohexane                 250

        benzene                                560
        toluene                                 480
        ethyl benzene                        430
        meta-xylene                          463
        para-xylene                           530
        ortho-xylene                          530

RE: auto ignition temperature

Ethylene and acetylene auto ignition temperature needs clarification.  These two chemicals decompose into C +CH4 + H2, raising the pressure by a factor of three and giving off large amounts of energy.  Their auto decomposition temperature is a function of pressure.  Quite a tricky pair.

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