Electroosmotic pump unit and assembly

An electroosmotic pump assembly, comprising:

• a plurality of electroosmotic pump units connected in series, each electroosmotic pump unit comprising:
• a first pump element including:
• a first tube having a first fluid inlet, a first fluid outlet, and a first inner surface, the first fluid inlet being electrically-grounded;
• and
• a first porous monolith positioned within the first tube between the first fluid inlet and the first fluid outlet and immobilized therein, the first porous monolith provided with a plurality of open pores having net positive surface charges;
• a second pump element including:
• a second tube having a second fluid inlet, a second fluid outlet, and a second inner surface, the second fluid inlet fluidly coupled with the first fluid outlet of the first pump element and the second fluid outlet being electrically grounded;
• and
• a second porous monolith positioned within the second tube between the second fluid inlet and the second fluid outlet and immobilized therein, the second porous monolith provided with a plurality of open pores having net negative surface charges;
• and
• an electrode electrically coupled to the first fluid outlet and the second fluid inlet for applying an electrical voltage across the first and second porous monoliths, wherein when the electric voltage is applied thereto, a fluid supplied to the first fluid inlet of the first pump element is caused to flow therefrom at a first pressure into the second pump element and therefrom via the second fluid outlet at a second pressure so that the fluid is discharged from the second fluid outlet at a third pressure which exceeds at least one of the first pressure and the second pressure.

An electroosmotic pump assembly, comprising:

• a first electroosmotic pump unit, including:
• a first pump element including:
• a first tube having a first fluid inlet, a first fluid outlet, and a first inner surface, the first fluid inlet being electrically-grounded;
• and
• a first porous monolith positioned within the first tube between the first fluid inlet and the first fluid outlet and immobilized therein, the first porous monolith provided with a plurality of open pores having net positive surface charges;
• a second pump element including:
• a second tube having a second fluid inlet, a second fluid outlet, and a second inner surface, the second fluid inlet fluidly coupled with the first fluid outlet of the first pump element and the second fluid outlet being electrically grounded;
• and
• a second porous monolith positioned within the second tube between the second fluid inlet and the second fluid outlet and immobilized therein, the second porous monolith provided with a plurality of open pores having net negative surface charges;
• and
• a first electrode electrically coupled to the first fluid outlet and the second fluid inlet for applying an electrical voltage across the first and second porous monoliths, wherein when the electric voltage is applied thereto, a fluid supplied to first fluid inlet of the first pump element is caused to flow therefrom at a first pressure into the second pump elements and therefrom via the second fluid outlet at a second pressure so that the fluid is discharged from the second fluid outlet at a third pressure which exceeds at least one of the first pressure and the second pressure;
• a second electroosmotic pump unit including:
• a third pump element including:
• a third tube having a third fluid inlet, a third fluid outlet, and a third inner surface, the third fluid inlet being electrically-grounded and fluidly coupled with the second fluid outlet;
• and
• a third porous monolith positioned within the third tube between the third fluid inlet and the third fluid outlet and immobilized therein, the third porous monolith provided with a plurality of open pores having net positive surface charges;
• a fourth pump element including:
• a fourth tube having a fourth fluid inlet, a fourth fluid outlet, and a fourth inner surface, the fourth fluid inlet fluidly coupled with the third fluid outlet of the third pump element and the fourth fluid outlet being electrically grounded;
• and
• a fourth porous monolith positioned within the fourth tube between the fourth fluid inlet and the fourth fluid outlet and immobilized therein, the fourth porous monolith provided with a plurality of open pores having net negative surface charges;
• and
• a second electrode electrically coupled to the third fluid outlet and the fourth fluid inlet for applying an electrical voltage across the third and fourth porous monoliths, wherein when the electric voltage is applied thereto, a fluid supplied to the third fluid inlet of the third pump element is caused to flow therefrom at a fourth pressure into the fourth pump element and therefrom via the fourth fluid outlet at a fifth pressure so that the fluid is discharged from the fourth fluid outlet at a sixth pressure which exceeds at least one of the fourth pressure and the fifth pressure.

A method of pumping a volume of a fluid, comprising:

• fluidly coupling a fluid source including a volume of a fluid with an electroosmotic pump unit, the electroosmotic pump unit comprising
• a first pump element including:
• a first tube having a first fluid inlet, a first fluid outlet, and a first inner surface, the first fluid inlet being electrically-grounded and fluidly coupled with the fluid source;
• and
• a first porous monolith positioned within the first tube between the first fluid inlet and the first fluid outlet and immobilized therein, the first porous monolith provided with a plurality of open pores having net positive surface charges;
• a second pump element including:
• a second tube having a second fluid inlet, a second fluid outlet, and a second inner surface, the second fluid inlet fluidly coupled with the first fluid outlet of the first pump element and the second fluid outlet being electrically grounded;
• and
• a second porous monolith positioned within the second tube between the second fluid inlet and the second fluid outlet and immobilized therein, the second porous monolith provided with a plurality of open pores having net negative surface charges;
• and
• an electrode electrically coupled to the first fluid outlet and the second fluid inlet for applying an electrical voltage across the first and second porous monoliths;
• and
• providing an electrical voltage to the electrode such that a volume of the fluid supplied to the first fluid inlet of the first pump element flows therefrom at a first pressure into the second pump element and therefrom via the second fluid outlet at a second pressure so that the fluid is discharged from the second fluid outlet at a third pressure which exceeds at least one of the first pressure and the second pressure.