"Ion exchange resin" is a polymer compound with functional groups (active groups with exchange ions), network structure, and insoluble. Usually spherical particles.
can also be divided into styrene resin and acrylic resin according to the type of its matrix. The type of chemically active groups in the resin determines the main properties and types of the resin. Firstly, it can be divided into two categories: cationic resin and anionic resin, which can perform ion exchange with the cation and anion in the solution.
Cationic resins are divided into strong acid and weak acid, anionic resins are further divided into strong alkaline and weak alkaline (or medium strong acid and medium strong alkaline).
The performance of ion exchange resin is mainly measured in two aspects: physical performance and adsorption performance. The physical properties include shape, particle size, color, density, particle swelling degree, mechanical strength and thermal stability, etc. The adsorption performance includes the total exchange capacity. Capacity under different media and PH value, adsorption equilibrium speed and desorption performance.
The shape of ion exchange resin is mostly spherical, and it is directly formed during polymerization, and the sphericity rate can reach more than 90%. The spherical resin has a good filling state and abrasion resistance is better than other shapes.
particle size is the particle diameter of the resin fully expanded in water. In water treatment, the commonly used resin particles are 0.3~1.2mm. The size and uniformity of resin particles have a greater impact on the ion exchange water treatment process.
resins are transparent and opaque, and have a variety of colors, such as milky white, light yellow, dark yellow and even dark brown. Gel-type resins are mostly transparent or translucent, while macroporous resins are opaque. The color of the resin does not reflect the performance of the resin. Even the resin products of the same model and different batches may have different colors. However, if the resin changes during use, it is often due to contamination of the resin, which should be paid attention to.
Resin density can be divided into dry density and wet density. Since the resins are used in the wet state in water treatment, the wet density is more practical.
The inert skeleton of the resin is usually hydrophobic, while the exchange group in the resin has considerable chemical activity, and the ion exchange resin is hydrophilic.