(269f) Synthesis and SCR Testing of SSZ-39

Ross Ransom¹, Jonathan Coote¹, Roger Moulton², Feng Gao², and Daniel F. Shantz¹*

¹Tulane University, New Orleans, Louisiana 70118 (USA)

²SACHEM, Inc., Austin, Texas 78704 (USA)

SSZ-39, the aluminosilicate anologue of the AEI (AlPO₄-18) topology, can be prepared in a straightforward manner using faujasite as an aluminum source¹. This material shows great promise as a catalyst for deNOx catalysis,^2,3 and thus a practical, simple, and scalable synthesis is something that would be highly desirable. A variety of organic SDAs have been shown to afford SSZ-39 at various levels of efficacy, including N,N-dimethyl-3,5-dimethylpiperidinium, the organic SDA employed here. Prior work has shown that not only does this SDA lead to SSZ-39 formation, but has suggested that the isomer identity has a significant effect on growth kinetics. ⁴

This talk will describe how the synthesis conditions used impact the growth kinetics and composition of the final material obtained from synthesis. There are four main findings from our synthesis study.⁵ The first is that using a faujasite with a Si/Al = 2.7 it is possible to form phase pure SSZ-39 across a wide gel Si/Al ratio (15-90), something not previously reported. Second, the yield from these syntheses changes consistently and clearly shows that the aluminum is the limiting reagent, and in all syntheses the yield based on aluminum is over 90%. Third, the trans isomer effect reported previously in the literature is confirmed and quantified across a wide range of cis/trans ratios in this work. Fourth, at an Si/Al = 45 one observes a clear increase in the Si/Al of the material obtained (from 8.6 – 10.5) as one increases the trans isomer content of SDA.

The talk will then describe our initial results in evaluating this material for SCR, showing how the SSZ-39 properties such as Si/Al, which can be controlled based on our synthesis studies, impact the catalytic properties of the SSZ-39 samples. These results will be put into the context of the voluminous literature around SSZ-13.

References

1. Maruo, T., Yamanaka, N., Tsunoki, N., Sadakane, M., Sano, T. . ChemLett 2014, 43, 302.
2. Albarracin-Caballero, J. D., Khurana, I., Di Iorio, J. R., Shih, A. J., Schmidt, J. E., Dusselier, M., Davis, M. E., Yezerets, A., Miller, J. T., Ribeiro, F. H., Gounder, R. Reaction Chemistry and Engineering 2017, 2, 168.
3. Moliner, M., Franch, C., Palomares, E., Grill, M., Corma, A. ChemComm 2012, 8264.
4. Dusselier, M., Schmidt, J.E., Moulton, R., Haymore, B., Hellums, M., Davis, M.E. Chem. of Materials 27, 7 (2015).
5. Ransom, R., Coote, J., Moulton, R., Gao, F., Shantz, D. F. Ind. Eng. Chem. Res. ASAP Article.