[hspwr]

I am trying to thoroughly clean a 55 gallon drum labeled Component A Isocyanate.

There is a thick layer of this stuff caked on the bottom of the barrel and it is very hard.  Can I neutralize it in some way, or soften it up enough to scrape off?

This is going to be a burn barrel and I don't want to be dispersing carcinogens into the air. 

Thanks.

[Arkcon]

Briefly, you can't scrub, reuse or burn out this drum, or any other vessel, unless you know exactly what's in it.  And the description is too ambiguous to be useful.  You can dispose of this drum, or return it to the manufacturer, or ask them.  But really it just isn't worth your time to try to remediate one drum.

[billnotgatez]

From
http://www.bayermaterialsciencenafta.com/businesses/pur/isocyanates.html

Finally, isocyanates will react with human tissue, such as skin, eyes and the respiratory tract, including the lungs. For this reason, you should always wear proper, recommended protective equipment and avoid breathing isocyanate vapors. Before working with isocyanates and polyurethanes in general, you must understand how to properly store and handle them