For acrylonitrile, a vacuum distillation process may be appropriate. It should be noted that a small quantity of polymerization inhibitor is needed in this process.
There are many options depending upon the starting purity. Vacuum distillation is typically required as one process, regardless of the other processes used first. Polymerization is always a potential problem with acrylic monomers as well as most other monomers. Knowledge and experience with the inhibitors. Depending upon the inhibitor, some distill over and others do not (but can have carryover from droplets entrained in the vapor flow). Lab scale distillation tests can typically provide the data you need in this regard.
For model reactions where I need clean monomers, we have good experiences with using a basic column removing the inhibitors like MEHQ/HQ at RT.
E.g. over basic Aluminum oxide, particle size ~150 mesh , 58 Å pore size such as available at:
http://www.sigmaaldrich.com/catalog/product/sial/199443?lang=en®ion=NL
For a few hundreds of ml take a column long 40 cm and ~4 cm diameter and pack it nice till half way; put some clean sea sand on top of it so that poring the monomer on top does not disturb the column. Slow tap the monomer at the bottom of the column, see picture : http://img.directindustry.com/images_di/photo-mg/104671-4795491.jpg
At the top of the column one often sees the yellowing boundary layer of the MEHQ/HQ present there. Do not make the flow too fast as the process needs some time, but within half an hour one could have > 100 ml depending upon the size of the column.
Take care as your monomer is now not stabilized anymore.......!
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