Polymerization state polysilicate ions

Aluminosilicate zeolites are normally synthesized under basic conditions. The introduction of OH- ions to the synthetic system will necessarily lead to the introduction of correlated cations. These positively charged cations play an important role in the polymerization of polysilicates and aluminates by affecting the polymeric state and their distribution, and have an important effect on the colloidal chemistry of aluminosilicate as well. In addition, cations existing in the synthetic system also have important effects on the formation of the framework structure of zeolites. For example, plenty of synthetic data indicated that a tight correlation between the formation of the SBU cages of zeolites and the charge and size of the cations existed, and this was named the templating effect of cations by R.M. Barrer.[191... 

The state and structure of silicate ions in sodium salt solution Sodium silicate solution (e.g., water glass) is one of the most commonly used chemicals in the synthesis of zeolites, which will supply the silicon species as well as Na+ and OH. Therefore, it is important to study the polymerization state and distribution of the polysilicate ions in sodium silicate solution under hydrothermal conditions. 

Their results indicated the presence of some highly polymerized silicate ions as well. According to the pre-described studies, it could be concluded that the state and distribution of polysilicate anions in both Na+ and K+ basic solutions are dependent on both [Si02] concentration and the alkalinity of the solution. Increased pH value and decreased [Si02] concentration result in an increased concentration of silicate monomer. 

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