Q & A > Question Details
How can we separate xylene (O, P and M) at 99% purity from reformate which is intended for making MS product.
Can it be done through distillation or does it require an extraction process in the aromatic solvent unit? What is the process called? Is there anywhere in India it is being done?
 
Answers
28/08/2020 A: Sridhar Balakrishnan, Bharat Oman Refineries Limited , laksrid@yahoo.com
Xylenes can be separated from BTX reformer reformate product by following thr PAREX (UOP ) or ARAMAX (AXENS) process. Other technologies are also available. Parayxlene is separated by a selective extraction process . metaxylene is also converted to paraxylene by an isomerisation process. Orthoxylene is separated by fa ractionation process. A PAREX unit is available at Reliance Jamnagar.
26/08/2020 A: Debdut Sadhu Sadhu, Honeywell UOP, dsadhu.1883@gmail.com
For separating o-,p- and m-xylenes, you have to have a UOP Parex or Axens Paramax unit. BP also offers crystallization units for separating xylenes. Yes, in India there are several units using UOP Parex like IOCL Panipat, Reliance Jamnagar, OMPL Mangalore. Reliance has BP technology also.
13/05/2020 A: keith bowers, B and B Consulting, kebowers47@gmail.com
Separation of Xylenes into their isomers requires fractional crystallization as well as high reflux distillation.
13/05/2020 A: Mohan Shyam Pathak, UOP A Honeywell Company, mohanspathak@gmail.com
The difference in boiling point is the main factor in favour of using a distillation column. In the present case where separation between o-Xylene, m-Xylene, p-Xylene is very low, use of a distillation column use is not economical.
Boiling points-
o-Xylene 144.3 Deg C
m-Xylene 139.1 Deg C
p-Xylene 138.2 Deg C

Therefore, an extraction process is economical. The name of this technology depends upon the licence owner. For example, UOP calls it Parex and Axens has named it Paramax technology.