硅铝酸钠溶液中^27Al和^29Si的核磁共振研究

Studies on ^(27)Al and ^(29)Si NMR Spectroscopies of Sodium Aluminosilicate Solutions

Aluminosilicate zeolites as one of the most important catalytic materials are widely applied in industrial reactions,and understanding of their synthetic mechanism is one of key factors in this field.27Al and 29Si NMR techniques are one of powerful tools for characterization of zeolite synthesis,but unfortunately the study on 27Al NMR spectra of aluminosilicate solutions is still argumentative,and the assignment of aluminosi-licate species in the solutions are challengeable.In this work,we have carefully compared 27Al NMR spectra of various aluminosilicate solutions,harmonizing the assignments reported previously.Furthermore,we assigned 29Si NMR spectra related to Al species.The peaks at δ:-75.1 and-82.5 in 29Si NMR spectrum are related to Q2 Al species,the peaks at δ:-84.5 and-90.8 are related to Q3 and Q4 Al species in aluminosilicate solutions,respectively.

Aluminosilicate zeolites as one of the most important catalytic materials are widely applied in industrial reactions, and understanding of their synthetic mechanism is one of key factors in this field. ^27Al and ^29Si NMR techniques are one of powerful tools for characterization of zeolite synthesis, but unfortunately the study on ^27 Al NMR spectra of aluminosilicate solutions is still argumentative, and the assignment of aluminosilicate species in the solutions are challengeable. In this work, we have carefully compared ^27Al NMR spectra of various aluminosilicate solutions, harmonizing the assignments reported previously. Furthermore, we assigned ^29Si NMR spectra related to Al species. The peaks at 8： -75.1 and -82. 5 in ^29Si NMR spectrum are related to Q^2 Al species, the peaks at δ： - 84.5 and - 90. 8 are related to Q^3 and Q^4 Al species in aluminosilicate solutions, respectively.