Distillation propylene-butylene reactor recycle.

[spekuljak]

Hello. Somebody has experience (good or bad)to recovery monomers, from propylene-butylene recycle stream (from polymerization reactor) by distillation, in packed column?

 

[dcasto]

which componets are you trying to seperate? The C3= from C4= or from other hydrocarbons?

Distillation is easy, but I would guess the polymer carry over would make a mess in the reboilers.

 

[spekuljak]

Thanks. Yes, the work is separate C3= from C4=. In general, this mixture is easy to distillate, but I am in searching if there were some reported or no reported cases that they were troublesome in packing columns (random or structured packing), based on the operative condition (pressure), and/or some properties of the mixture, related to its history (it comes from a polymerization reactor).

 

[dcasto]

Their boiling points are 70 degrees apart so it shouldn't be a problem. Like I said before, the biggest concern would be polymers in the reboiler, so a low bottom temp would be best. I'd look at a LP tower at 50 psig the top would be 20 F and bottom 100F. You'd use a heat pump for the energy system.

 

[Compositepro]

From what I've read (no experience) polymerization problems also occur where vapors condense because polymerization inhibitors have been removed in condensed vapors.