Molecular sieve manufacturer talks about direct synthesis, post-treatment, and modification of molecular sieves

Due to its unique shape selection performance and high internal specific surface area, molecular sieve materials have been widely used in catalysis, adsorption, and ion exchange fields. The crystal structure (such as eight membered rings, ten membered rings, twelve membered rings, and even larger pore structures, as well as one-dimensional, two-dimensional, and three-dimensional channel systems) and skeleton composition (such as silicon aluminum ratio, acidity, and hydrophilicity/hydrophobicity) of these materials are the main determining factors for their widespread application in these fields.
As of July 2009, the Structural Professional Committee of the International Molecular Sieve Association has confirmed 191 types of skeleton structures for molecular sieve materials. Theoretical research shows that this number is only a small part of the possible structure of molecular sieves. Developing new methods for preparing molecular sieves with suitable structures and skeleton compositions has become a major challenge in designing and applying molecular sieves suitable for specific fields. In principle, there are two ways to achieve this goal: direct synthesis method; Post processing method and modification method.
Firstly, a brief discussion is given on the direct synthesis method, which involves reinserting Al atoms from Al (NO3) 3 solution into the molecular sieve framework under acidic conditions, and using acetic acid for hydrothermal dealumination of the molecular sieve to obtain pure silicon molecular sieve. The direct synthesis method is the main approach for the preparation of molecular sieves. During the crystallization process, there are many factors that affect the structure of molecular sieve products, mainly including the composition of the synthesis system, crystallization temperature, crystallization time, and the preparation process of the synthesis system, such as aging and crystallization technology. In addition, according to literature reports, the selection of structural directing agents plays a crucial role in the selective formation of molecular sieve frameworks. In short, direct synthesis methods often fail to obtain molecular sieve materials with suitable properties for specific applications.
In addition to the direct synthesis method, the post-synthesis method provides a more practical and feasible way to obtain molecular sieves that meet the required skeleton composition and other properties. They follow the same principle: they hope that Al or Si atoms enter the lattice position better than other heteroatoms. These two methods involve reinserting Al atoms from AI (N03) 3 solution into the molecular sieve framework under acidic conditions, and using acetic acid to undergo hydrothermal dealumination treatment on the molecular sieve to obtain pure silicon molecular sieve. In the future, this method will be a practical and effective tool for preparing these siliceous aluminate molecular sieves until a more economical new method for directly synthesizing these siliceous aluminate molecular sieves is developed. It provides a new approach for the synthesis of high-quality molecular sieves for structural characterization and determination of molecular sieves. Hunan Providence New Materials Co., Ltd is a professional molecular sieve manufacturer which can provide USY zeolite, NaY zeolite, REY zeolite, ZSM-5 zeolite, welcome to consult.