Method for preparing honeycomb molecular sieve adsorbent from red mud

Abstract

The invention discloses a method for preparing a honeycomb molecular sieve adsorbent by using red mud; the honeycomb molecular sieve adsorbent is prepared from the following raw materials: molecular sieve raw powder, water, red mud, an organic auxiliary agent, anti-crack glass fiber and citric acid, and the honeycomb molecular sieve adsorbent is obtained by mixing, pugging, extrusion forming, drying and roasting the raw materials. The red mud solid waste is recycled, meanwhile, the adsorbent has the advantages of being high in strength, large in adsorption capacity and good in regeneration effect, the adsorbent can be used for industrial VOCs adsorption, the production cost is reduced, meanwhile, a large amount of red mud can be fully recycled, no residues exist after roasting, the adsorption performance is not affected, the product quality is improved, the fracture toughness of the honeycomb zeolite adsorbent is improved, and the integrity of the adsorbent is ensured.

Description

technical field [0001] The invention relates to the technical field of molecular sieves, in particular to a method for preparing a honeycomb molecular sieve adsorbent by using red mud. Background technique [0002] Molecular sieve is a kind of aluminosilicate, which is mainly composed of silicon and aluminum connected by oxygen bridges to form a hollow skeleton structure. Metal ions with low and large ionic radius and combined water, because the water molecules are lost continuously after heating, but the crystal skeleton structure remains unchanged, many cavities of the same size are formed, and the cavities have many microscopic particles of the same diameter. The pores are connected, and the material molecules smaller than the diameter of the pores are adsorbed inside the cavity, and the molecules larger than the pores are squeezed out, so that the molecules of different sizes and shapes are separated until the sieving of molecules, so it is called molecular sieve. Red mu...

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Problems solved by technology

[0003] At present, there are generally two methods for the preparation of honeycomb molecular sieve VOCs adsorbents. One is the molding method, that is, the adsorbent is mixed with certain inorganic fillers, extruded and formed into a honeycomb shape, but its mechanical strength is low. The medium is fragile, and the second is the coating method, that is, the molecular sieve is coated on the honeycomb carrier. The obtained adsorbent has the characteristics of high mechanical strength, but the coating is easy to fall off, and the coating effect directly affects its adsorption performance. , to a certain extent, limits the scope of application of molecular sieves. Secondly, the existing integral extruded honeycomb molecular sieves not only have fewer wall thickness holes and many cracks, but also have low strength, large wear (very easy to drop powder), and low utilization rate of molecular sieves. For the zeolite adsorption wheel for VOCs purification, it is usually required that the core adsorption material integral honeycomb molecular sieve has a pore density of ≥300 days and a wall thickness of ≤0.25mm. It is still the product specification of the integral extruded honeycomb molecular sieve, which does not meet the requirements of the integral honeycomb molecular sieve for the zeolite adsorption runner for VOCs purification

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