2 replies to this topic

[Hamza1111]

Hello !!

I am a Final Year Student and currently working on my project ( Production of Diisocyanates by Phosgenationn of Diamines in Gas Phase ) specifically Hexamethylene Diisocyanate (HDI)
For the ease of situation, we considered only one residual product i.e Hexamethylene Diisocyanate Trimer. The problem is I can't find much data on this compound and now in my product purification step, I opted vacuum distillation ( keeping in view the thermal unstability of HDI). But for the design of vacuum distillation columnn, I need data (Anntoinies Coefficients, viscosities ) on the HDI trimer as well which is unable  to find. Kindly guide how to tackle this hurdle 
thank you 

[Pilesar]

How I would approach this (knowing nothing about HDI)...

Molecular weight is high. Isn't this a solid? If a solid, then purification would not be by distillation -- just driving off lighter impurities.

What are the other components that are impurities? Those would be the important properties to know. Find a temperature and pressure where the HDI is unharmed and the impurities are chased away. Turn and tumble the solid HDI so there is a path for the impurities to leave the mix.

Maybe a crystalization step would yield pure HDI.

As for HDI properties, look to the sales specs for companies that make HDI. If not in the sales specs, then maybe info is in the Safety Data Sheet for the chemical.

[breizh]

Hi,

Not much info on Internet! Some info on TDS about VP@ 20/25C.

I tried Yaw's data base (5000 components), same with Korean Data base, no success.

You probably need to get access to a data bank for this type of product with the support of your Uni. Cost associated with.

https://www.ddbst.com/

If I remember well, this is the kind of technology used to purify the product.

https://www.3v-tech....or/applications

 

Breizh

Attached Files

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