Ion exchange is a special solid adsorption process that is carried out in an electrolyte solution of an ion exchanger. A typical ion exchanger is a solid particulate material that is insoluble in water, i.e., an ion exchange resin. It can extract a certain cation or anion from the electrolyte solution, and exchanges another ion with the same charge symbol contained in its own equivalent amount and releases it into the solution. This is called ion exchange. Depending on the type of ion exchanged, the ion exchanger can be divided into two major categories: cation exchangers and anion exchangers.
a. First electrolyte ions (calcium, magnesium, iron, sodium ions) pass through the liquid film into the resin surface;
b. Ions enter the interior of the resin;
c. Ion exchange;
d. H ion or OH ion diffused to the outside of the resin;
e. H ions or OH ions enter the water to form H2O. The double bed is also called a double bed.
The double bed is a series connection of two different ion exchange exchangers, such as a strong acid cation exchange resin and a strong basic anion exchange resin. The device consisting of a tandem bed and a female bed in series is called a double bed.
The water first passes through the sun bed to remove positively charged ions (such as Ca2+, Mg2+, K+, Na+), and replaces the H+ ions into the water; then removes the negative in the water.
Ions (such as SO2-4, Cl-, HCO-3) and displace OH- ions into the water. At the same time, H+ ions and OH- ions combine to form water H2O, thereby achieving deionization.