Synthesis of NaHS zeolite using microwave assisted alkali activation of coal fly ash: preparation, mechanism, application

ABSTRACT

High value-added NaHS zeolite was prepared using the microwave-assisted alkali fusion hydrothermal method from industrial solid waste coal fly ash as raw material without adding silicon and aluminum sources. The effect of mass ratio of alkali to coal fly ash, crystallization temperature, and crystallization time on the preparation of NaHS zeolite was investigated. The NaHS zeolite was characterized using XRD, SEM, BET, and FT-IR. The experimental results showed that the NaHS zeolite with complete crystal structure could be synthesized at m(sodium hydroxide):m(coal fly ash) = 2:1, crystallization temperature of 140°C, and crystallization time of 48 h. The prepared HS zeolite had high purity, complete crystal structure, and uniform grain size (2 μm). The NaHS zeolite was beneficial for CO₂ adsorption properties with 110.9 cm³/g at 25°C.

KEYWORDS:

• Alkali fusion hydrothermal modification
• coal fly ash
• crystallization time
• crystallization temperature
• NaHS zeolite

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/15567036.2022.2154413

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the funding from Natural Science Foundation of Liaoning Province (2022-MS-354), Science and Technology Plan Project of Liaoning Province (2022JH1/10800065), the Education Department Excellent Talents Training Program of Liaoning Province (2020LNQN21), the Excellent Talents Training Program of University of Science and Technology Liaoning (2019RC12), and International Collaborative Centre for Carbon Futures is also acknowledged