What Are The Main Properties Of Ion Exchange Resin

Ion exchange resin is a polymer compound, so its performance is different due to the manufacturing process, raw material formulation, polymerization temperature, crosslinking agent, etc., its main performance is divided into two parts.
(1) Physical properties
The appearance of the resin is a transparent or translucent substance, because of its different composition, different colors, such as styrene resin is yellow, but also black and russet, but it has little effect on the performance. Under normal circumstances, the raw material impurities or crosslinking agents are more, and the color of the resin is slightly darker (but the color of the resin sometimes changes during the operation for various reasons). The shape of the resin is spherical, and the ball rate is required to reach more than 90%.
② The size of the particle size of the resin will affect the exchange speed, pressure loss, backwash effect, etc. The particle size can not vary too much. The particles of ion exchange resin used for water treatment should be 20 to 40 mesh. The representation of particle size is expressed in terms of effective particle size and non-uniformity coefficient.
③ The density is related to the water treatment process and the amount of resin filling. The density is expressed in the following ways: dry true density (generally about 1.6g/cm3), wet true density (generally between 1.04 and 1.30g/cm3), apparent wet density (generally between 0.60 and 0.80g/cm3).
The higher the moisture content of the resin, the larger the porosity and the smaller the crosslinking degree.
⑤ Swelling rate After soaking in water, the resin should swell, which is related to the degree of crosslinking, active groups, exchange capacity, electrolyte density in water, and the nature of exchangeable ions. In the process of exchange and regeneration, the resin will expand and shrink, and the multiple expansion and shrinkage resin is easy to break.
⑥ Wear resistance reflects the mechanical strength of the resin. It should ensure that the annual resin consumption does not exceed 7%.
⑦ The soluble resin contains low polymers to be gradually dissolved, and colloidal dissolution will also occur during the use of the resin.
⑧ Heat resistant positive resin can withstand about 100℃, strong alkaline negative resin can withstand 60℃, weak alkaline negative resin can withstand 80℃. However, when it is lower than or equal to 0 ° C, it is easy to freeze and break.
⑨ Conductivity Dry resin does not conduct electricity, wet resin can be conductive.
(2) Chemical properties
① The exchange reaction of ion exchange resin is reversible, so it can be exchanged, it can also be regenerated, and it can be used repeatedly.
② It has acid and alkali. H+ type cation exchange resin and OH- type anion exchange resin have the same properties as electrolyte acids and bases, and can ionize H+ and OH- in water.
③ With neutralization and hydrolysis properties. Because of its electrolyte properties, it can be neutralized with acids and bases, and can also be hydrolyzed.
④ The ability of ion exchange resin to absorb various ions is different, and it is selective.
⑤ Exchange capacity. It's how many ions it exchanges. According to the shape of the resin, it can be divided into equilibrium exchange capacity, full exchange capacity, working exchange capacity, etc.