Organic solvent purifier and method of using
View Patent ↗A purifier for removing metal, such as chromium, from an organic solvent is disclosed. The purifier comprises a housing having a fluid inlet and a fluid outlet in fluid communication with the fluid inlet; a volume of ion-exchange resin disposed within the housing downstream of the fluid inlet; and a filtration member downstream of the volume of ion-exchange resin, the filtration member comprising at least one microporous membrane having a substantially neutral surface and a microporous polytetrafluoroethylene membrane downstream of the at least one microporous membrane. A method for removing metal, including chromium, from an organic solvent using a purifier of the invention is also disclosed.
1. A purifier for removing chromium from an organic solvent, comprising:
a housing having a fluid inlet and a fluid outlet in fluid communication with the fluid inlet;
a volume of ion-exchange resin disposed within the housing downstream of the fluid inlet; and
a filtration member disposed downstream of the volume of ion-exchange resin, the filtration member comprising:
at least one amide-modified microporous polytetrafluoroethylene membrane having a substantially neutral surface with an electrostatic potential of about 0; 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.
2. 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; 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 amide-modified microporous polytetrafluoroethylene membrane having a substantially neutral surface with an electrostatic potential of about 0; 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.
3. The purifier of claim 1 , wherein a surface of the microporous polytetrafluoroethylene ion-exchange membrane is modified with sulfonic acid.
4. The purifier of claim 1 , wherein the microporous polytetrafluoroethylene ion-exchange membrane has a pore size rating by bubble point of about 1 nanometer to about 50 nanometers.
5. The purifier of claim 4 , wherein the microporous polytetrafluoroethylene ion-exchange membrane has a pore size rating by bubble point of about 1 nanometer to about 25 nanometers.
6. The purifier of claim 1 , wherein the at least one amide-modified microporous membrane having a substantially neutral surface and the microporous polytetrafluoroethylene ion-exchange membrane are bonded to one another in the filtration member.
7. The purifier of claim 1 , wherein the at least one amide-modified microporous membrane having a substantially neutral surface and the microporous polytetrafluoroethylene ion-exchange membrane are disposed adjacent to one another in the filtration member.
8. The purifier of claim 1 , wherein the at least one amide-modified microporous membrane having a substantially neutral surface and the microporous polytetrafluoroethylene ion-exchange membrane are each pleated.
9. The purifier of claim 1 , further comprising an ion-exchange resin vessel that contains the volume of ion-exchange resin.
10. The purifier of claim 9 , wherein the ion-exchange resin vessel comprises a net material or frit.
11. The purifier of claim 1 , further comprising a liquid distributor downstream of the volume of ion-exchange resin and upstream of the filtration member.
12. The purifier of claim 1 , wherein the organic solvent is an alcohol.
13. The purifier of claim 12 , wherein the alcohol is isopropanol.
14. The purifier of claim 1 , wherein the filtration member comprises at least three amide-modified microporous polytetrafluoroethylene membranes, each having a substantially neutral surface, and the microporous polytetrafluoroethylene ion-exchange membrane is downstream of the at least three amide-modified microporous membranes.
15. 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; 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 amide-modified microporous membranes, each having a substantially neutral surface with an electrostatic potential of about 0; and
a microporous polytetrafluoroethylene ion-exchange membrane downstream of the at least three amide-modified microporous membranes,
wherein each amide-modified 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 μ; 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.
16. A method for removing chromium from an organic solvent, the method comprising:
providing a flow of an organic solvent comprising chromium and
passing the flow of the organic solvent through a purifier to thereby remove chromium from the organic solvent, the purifier comprising:
a housing having a fluid inlet and a fluid outlet in fluid communication with the fluid inlet;
a volume of ion-exchange resin disposed within the housing downstream of the fluid inlet; and
a filtration member disposed downstream of the volume of ion-exchange resin, the filtration member comprising:
at least one amide-modified microporous polytetrafluoroethylene membrane having a substantially neutral surface with an electrostatic potential of about 0; 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.
17. The purifier of claim 2 , wherein a surface of the microporous polytetrafluoroethylene ion-exchange membrane is modified with sulfonic acid.
18. The purifier of claim 2 , wherein the microporous polytetrafluorethylene ion-exchange membrane has a pore size rating by bubble point of about 1 nanometer to about 50 nanometers.
19. The purifier of claim 18 , wherein the microporous polytetrafluorethylene ion-exchange membrane has a pore size rating by bubble point of about 1 nanometer to about 25 nanometers.
20. The purifier of claim 2 , wherein the at least one amide-modified microporous membrane having a substantially neutral surface and the microporous polytetrafluoroethylene ion-exchange membrane are bonded to one another in the filtration member.
21. The purifier of claim 2 , wherein the at least one amide-modified microporous membrane having a substantially neutral surface and the microporous polytetrafluoroethylene ion-exchange membrane are disposed adjacent to one another in the filtration member.
22. The purifier of claim 2 , wherein the at least one amide-modified microporous membrane having a substantially neutral surface and the microporous polytetrafluoroethylene ion-exchange membrane are each pleated.
23. The purifier of claim 2 , further comprising an ion-exchange resin vessel that contains the volume of ion-exchange resin.
24. The purifier of claim 23 , wherein the ion-exchange resin vessel comprises a net material or frit.
25. The purifier of claim 2 , further comprising a liquid distributor downstream of the volume of ion-exchange resin and upstream of the filtration member.
26. The purifier of claim 2 , wherein the organic solvent is an alcohol.
27. The purifier of claim 26 , wherein the alcohol is isopropanol.
28. The purifier of claim 2 , wherein the filtration member comprises at least three microporous amide-modified membranes, each having a substantially neutral surface, and the microporous polytetrafluoroethylene ion-exchange membrane is downstream of the at least three amide-modified microporous membranes.