Separation system, components of a separation system and methods of making and using them

• US 7,922,908 B2
• Filed: 01/19/2006
• Issued: 04/12/2011
• Est. Priority Date: 06/26/2002
• Status: Active Grant

• Current Assignee: Dionex Corporation (Thermo Fisher Scientific Incorporated)
• Original Assignee: Dionex Corporation (Thermo Fisher Scientific Incorporated)
• Inventors: Jiang, Tao, Xu, Mingcheng, Xie, Shaofeng, Allington, Robert W.
• Primary Examiner(s): Therkorn; Ernest G
• Application Number:
  US11/337,071
• Publication Number:
  US 20060207939A1
• Time in Patent Office: 1,909 Days
• Field of Search: 210/656, 210/635, 210/659, 210/748.01, 210/198.2, 210/502.1, 95/88, 961/01
• US Class Current: 210/635
• CPC Class Codes: B01D 15/206 Packing or coating
• CPC Class Codes: B01J 19/0013 Controlling the temperature of the process
• CPC Class Codes: B01J 19/18 Stationary reactors having moving elements inside B01J19/08, B01J19/26 take precedence
• CPC Class Codes: B01J 20/283 based on silica
• CPC Class Codes: B01J 20/285 based on polymers
• CPC Class Codes: B01J 20/3064 Addition of pore forming agents, e.g. pore inducing or porogenic agents
• CPC Class Codes: B01J 2219/00162 controlling the pressure
• CPC Class Codes: B01J 2220/54 Sorbents specially adapted for analytical or investigative chromatography
• CPC Class Codes: B01J 2220/82 Shaped bodies, e.g. monoliths, plugs, tubes, continuous beds
• CPC Class Codes: B01J 8/0005 Catalytic processes under superatmospheric pressure non-catalytic processes B01J3/00
• CPC Class Codes: G01N 2030/522 pressure
• CPC Class Codes: G01N 2030/528 Monolithic sorbent material
• CPC Class Codes: G01N 2030/567 coating
• CPC Class Codes: G01N 30/30 of temperature
• CPC Class Codes: G01N 30/56 Packing methods or coating methods

Abstract

Permeable polymeric monolithic materials are prepared in a column casing. In one embodiment, the permeable polymeric monolithic materials are polymerized while pressure is applied through a piston having a smooth piston head in contact with the polymerization mixture. The pressure eliminates wall effect and changes the structure in the column. Similarly, some columns that have a tendency to swell in the presence of aqueous solutions and pressurized while the solution is applied to prevent swelling and wall effect. This procedure also changes the structure in the column. The size of the separation effective openings can be controlled by the amount of the pressure and pores eliminated. Uniformity in the direction flow is improved by controlling polymerization with radiation rather than with conducted heat.

Claims

1. A method of making a monolithic chromatographic column comprising the steps of:

preparing a polymerization mixture including at least one vinyl monomer, an initiator, and a porogen;

inserting said polymerization mixture into the walls of a chromatographic column

polymerizing said polymer mixture under a pressure of at least 80 psi during at least part of said polymerization, whereby sufficient pressure is applied to prevent voids from being formed caused by vacuum due to shrinkage during polymerization in a temperature controlled chamber during at least part of the time pressure is being applied to the polymerization mixture to form a polymer plug; and

washing the polymer plug to remove the porogen.

2. The method of claim 1 in which polymerizing is performed under a pressure of at least 80 psi during at least part of said polymerizing.

3. The method of claim 1 in which polymerizing is performed under a pressure of at least 150 psi during at least part of said polymerizing.

4. The method of claim 1 in which polymerizing is performed under a pressure of at least 180 psi during at least part of said polymerizing.

5. The method of claim 1 in which the pressure is applied in intervals of increasing pressures.

6. The method of claim 1 in which said pressure is sufficient to prevent voids from being formed inside the polymer plug.

7. The method of claim 1 in which said controlled elevated temperature is increased gradually during polymerization by controlling the temperature on the outside of the chamber.