Organic Solvent Purifier And Method Of Using

A purifier for removing chromium from an organic solvent, comprising:

• a cylindrical housing having a longitudinal axis, a fluid inlet and a fluid outlet in fluid communication with the fluid inlet;
• a volume of ion-exchange resin disposed within the cylindrical housing downstream of the fluid inlet, the ion-exchange resin being adapted to remove chromium species from the organic solvent;
• and
• a pleated filtration member disposed concentrically around the longitudinal axis within the cylindrical housing and downstream of the volume of ion-exchange resin, the pleated filtration member comprising:
• at least one microporous polytetrafluoroethylene membrane having a substantially neutral surface modified with amide;
• and
• a microporous polytetrafluoroethylene ion-exchange membrane downstream of the at least one amide-modified microporous polytetrafluoroethylene membrane,
• wherein the at least one amide-modified microporous polytetrafluoroethylene membrane has a pore size rating greater than the pore size rating of the microporous polytetrafluoroethylene ion-exchange membrane and less than or equal to about 10 μm;
• and the microporous polytetrafluoroethylene ion-exchange membrane has a pore size rating by bubble point of about 1 nanometer to about 100 nanometers.

A purifier for removing chromium from an organic solvent, comprising:

• a cylindrical housing having a longitudinal axis, a fluid inlet and a fluid outlet in fluid communication with the fluid inlet;
• a volume of ion-exchange resin disposed within the cylindrical housing downstream of the fluid inlet, the ion-exchange resin being adapted to remove chromium species from the organic solvent;
• and
• a pleated filtration member disposed concentrically around the longitudinal axis within the cylindrical housing and downstream of the volume of ion-exchange resin, the pleated filtration member comprising:
• at least three microporous membranes, each having a substantially neutral surface;
• and
• a microporous polytetrafluoroethylene ion-exchange membrane downstream of the at least three microporous membranes,
• wherein each microporous membrane is a microporous polytetrafluoroethylene membrane modified with amide and has a pore size rating greater than the pore size rating of the microporous polytetrafluoroethylene ion-exchange membrane and less than or equal to about 10 μm;
• and the microporous polytetrafluoroethylene ion-exchange membrane has a surface modified with sulfonic acid and a pore size rating of about 1 nanometer to about 25 nanometers.