System and method for using ultramicroporous carbon for the selective removal of nitrate with capacitive deionization

1 . A method for making a carbon aerogel electrode material having slit-shaped pores forming first pores, and a plurality of second pores, the method comprising:

making a wet organic sol-gel block;

slicing the wet organic sol-gel block into sheets each having a thickness of about 300 μm to about 700 μm, to form wet sol-gel sheets;

washing the wet sol-gel sheets with DI water and subsequently exchanged for acetone;

sandwich wet sol-gel sheets between porous silicon carbide sheets, to create a sol-gel form;

drying the sol-gel form to form a dried sol-gel form;

carbonizing the dried sol-gel form at a temperature of from about 900° C. to about 1000° C., for from about 2 hours to about 4 hours;

activating the carbonized sol-gel under carbon dioxide flow, for from about 0.5 hour to about 1.5 hours, at from about 900° C. to about 1000° C., while being exposed to a CO 2 flow of about 2 liters per minute in a furnace; and

wherein the slit-shaped pores are below 1 nm in width, and the plurality of second pores form micron-sized pores, and wherein the second pores help to form a ligament-like structure having a plurality of ligaments formed with a random distribution throughout a thickness of the carbon aerogel electrode material, and the slit-shaped pores are present on the ligaments.

2 . The method of claim 1 , wherein the wet organic sol-gel form is a resorcinol-formaldehyde sol-gel.

3 . The method of claim 2 , wherein the making a wet organic sol-gel form comprises:

making an aqueous solution of resorcinol and formaldehyde;

mixing the aqueous solution with an alcohol and an acid to make a sol-gel precursor;

curing the sol-gel precursor in a mold; and

aging the sol-gel.

4 . The method of claim 1 , wherein the carbonizing is conducted under nitrogen.