The effect and function of template agent on the synthesis of ZSM molecular sieve

In the process of molecular sieve synthesis, template agent plays a crucial role. The template agent is an organic molecule that can guide the crystal growth of the molecular sieve through the intermolecular interaction and determine its final crystal structure.
First, the template agent can affect the synthesis process of molecular sieve. In the synthesis process of molecular sieve, template agent can be used as a “guide” to help synthesize molecular sieve with specific pore size and shape. This is because the template agent is able to recognize and coordinate to specific inorganic silicate species, thereby controlling their growth direction and rate. Secondly, the template agent can also affect the pore size and shape of the molecular sieve.
Molecular sieves with different pore sizes and shapes can be synthesized with different template agents, because the molecular size and shape of the template agent determine the pore size and shape of the final molecular sieve.
For example, a decyl template can be used to synthesize ZSM-5 molecular sieve with a ten-membered cyclopore structure, while a dodecyl template can be used to synthesize ZSM-12 molecular sieve with a twelve-membered cyclopore structure.
In addition, template agent can also affect the acidity and stability of molecular sieve. Different types of template agents can impart different acidity to molecular sieve, because the template agent can interact with the acidic center of the molecular sieve through its functional groups.
At the same time, different template agents can also affect the thermal stability and hydrothermal stability of molecular sieve. For example, the use of an amide template can significantly improve the thermal stability of ZSM-5 molecular sieves.
In conclusion, the template agent plays an important role in the synthesis of ZSM molecular sieve.
By selecting suitable template agent, molecular sieves with specific pore size and shape, good acidity and stability can be synthesized, so as to better meet the needs of various catalytic reactions.