D001 macroporous strong acid cation exchange resin is often divided into two types: gel type and macroporous type.
The polymer skeleton of the gel-type resin has no capillary pores inside when it is dried. It swells when absorbing water, forming very fine pores between macromolecular chain links, usually called micro-pores. The average pore diameter of the wet resin is 2 to 4 nm (2×10-6 to 4×10-6 mm).
This type of resin is more suitable for adsorption of inorganic ions, their diameter is relatively small, generally 0.3 ~ 0.6nm. This type of resin cannot absorb macromolecular organic substances, because the latter has a large size, such as a protein molecule diameter of 5-20 nm, and cannot enter the microscopic pores of this type of resin.
The macroporous resin is formed by adding a porogen during polymerization to form a skeleton of a porous sponge-like structure, with a large number of micropores inside, and then introducing exchange groups. It coexists with micropores and macro-pores. The pore size of the wetting resin is 100-500nm, and its size and quantity can be controlled at the time of manufacture. The surface area of the channels can be increased to more than 1000m2/g. This not only provides good contact conditions for ion exchange, shortens the distance of ion diffusion, but also increases the activity of many chain links. The van de waal's force between molecules produces molecular adsorption, which can adsorb all kinds of particles like activated carbon. This kind of non-ionic substance expands its function. Some macroporous resins without exchange functional groups can also adsorb and separate a variety of substances, such as phenols in chemical plant wastewater.
The pores inside the macroporous resin are many and large, the surface area is large, the activity is large, the ion diffusion speed is fast, and the ion exchange speed is also much faster, which is about ten times faster than the gel type resin. It has fast action and high efficiency when used, and the processing time required is shortened. Macroporous resin also has many advantages: resistance to swelling, not easy to crack, oxidation resistance, heat resistance and temperature change, and easy adsorption and exchange of organic macromolecular substances, so it has strong anti-pollution ability