Zeolite-templated carbons as effective sorbents to remove methylsiloxanes and derivatives: A computational screening

Shiru Lin, Universidad de Puerto Rico
Kaitlyn A. Jacoby, Elizabethtown College
Jinxing Gu, Universidad de Puerto Rico
Dariana R. Vega-Santander, Recinto Universitario de Mayagüez
Arturo J. Hernández-Maldonado, Recinto Universitario de Mayagüez
Zhongfang Chen, Universidad de Puerto Rico

Abstract

Though widely used in our daily lives, volatile methylsiloxanes and derivatives are emerging contaminants and becoming a high-priority environment and public health concern. Developing effective sorbent materials can remove siloxanes in a cost-effective manner. Herein, by means of Grand Canonical Monte Carlo (GCMC) simulations, we evaluated the potentials of the recently proposed 68 stable zeolite-templated carbons (ZTCs) (PNAS 2018, 115, E8116-E8124) for the removal of four linear methylsiloxanes and derivatives as well as two cyclic methylsiloxanes by the calculated average loading and average adsorption energy values. Four ZTCs, namely ISV, FAU1, FAU3, and H8326836, were identified with the top 50% adsorption performance toward all the six targeted contaminants, which outperform activated carbons. Further first principles computations revealed that steric hindrance, electrostatic interactions (further enhanced by charge transfer), and CH-π interactions account for the outstanding adsorption performance of these ZTCs. This work provides a quick procedure to computationally screen promising ZTCs for siloxane removal, and help guide future experimental and theoretical investigations.