Molecular sieve is a crystalline silicate or aluminosilicate, which is a pore and cavity system with molecular size (usually 0.3nm to 2.0nm) formed by connecting silicon oxygen tetrahedron or aluminum oxide tetrahedron through oxygen bridge bond, Coconut shell activated carbon Beijing Therefore, it has the characteristics of screening molecules. However, with the deepening of molecular sieve synthesis and application research, researchers have found phosphoaluminate molecular sieves, and the skeleton elements (silicon or aluminum or phosphorus) of molecular sieves can also be replaced by B, Ga, Fe, Cr, Ge, Ti, V, Mn, Co, Zn, Be and Cu, and the size of its pores and cavities can also reach more than 2 nm, Coconut shell activated carbon major Therefore, molecular sieves can be divided into silicon aluminum molecular sieves, phosphorus aluminum molecular sieves and skeleton heteroatom molecular sieves according to the composition of skeleton elements;

Coconut shell activated carbon major The addition of retention aids in the wet end of paper making is an important way to improve filler retention, which has been widely used in industrial production. Some studies reported that clinoptilolite (particle size 0.5-2 μ m) was used as a microparticle retention aid to compare the retention effect with silica and bentonite microparticle retention aid systems. The retention effect of clinoptilolite retention aid is equivalent to that of the silica microparticle retention aid system with the same dosage, which is far better than that of the bentonite microparticle retention aid system. And the use of zeolite as paper filler eliminates the need for additional microparticle retention aids. It is also reported that the retention rate of TiO2 nanoparticles can be significantly improved by using zeolite molecular sieves as retention aids in the preparation of photocatalytic paper. Compared with starch and cationic polymer, zeolite molecular sieve microparticle retention aids have better effects on improving the retention and drainage properties of paper stock and improving the uniformity of paper. Coconut shell activated carbon major The use of zeolite particle retention aids can effectively avoid flocculation between fibers, and help to form fiber particle fiber flocculating particles. In addition, it can also support titanium dioxide nanoparticles.

Zeolite molecular sieves have the following potential applications. Coconut shell activated carbon Direct selling (1) Due to the high whiteness of molecular sieves, the optical properties of paper can be improved. (2) It can improve the loose thickness and printability of the paper. (3) Molecular sieves can be used to prepare special papers such as gas filter paper, rust proof paper and photocatalysis paper due to their open structure. (4) It can be used for low weight newsprint and book paper, and can effectively avoid ink penetration. (5) Its ion exchange performance can avoid resin and filler deposition. Coconut shell activated carbon major (6) It can be used for phenolic paper laminate to improve its corrosion resistance in humid environment. Phenolic paper laminates used as insulators in printed circuit boards and integrated circuits will be affected by electrolytic corrosion when exposed to high humidity. (7) It is mixed with titanium dioxide (TiO2) filler to produce high-quality white paper.

Coconut shell activated carbon major The holes and channels inside the zeolite crystal are uniform and fixed in size, and the diameter of the holes is generally 6~15A. Only molecules with smaller diameter can enter the cavity through the zeolite channel and be adsorbed, while large molecules cannot enter the cavity and be adsorbed. Zeolite is also called molecular sieve because of its selective adsorption performance. Coconut shell activated carbon Beijing However, silica gel, activated carbon and other adsorbents have no selective adsorption and screening performance due to their non uniformly fixed pore sizes and large changes. The main material of honeycomb zeolite adsorbent is natural zeolite. The manufacturer of zeolite is composed of silica Inorganic microporous material composed of al_2o_3 and alkaline metal or alkaline earth metal, with inner pore volume accounting for 40-50% of the total volume and specific surface area of 100-500 m2/g, is characterized by high temperature resistance, non flammability, good thermal stability and hydrothermal stability. It is an efficient molecular sieve carrier with good adsorption performance, no secondary pollution, and can be regenerated at high temperature. Compared with honeycomb activated carbon, its performance is about 25% of its efficiency, However, it is widely used in the fields of adsorption, separation, catalysis and environment due to its high temperature resistance and difficult ignition. It is more suitable for the treatment of organic waste gas with large air volume and low concentration.