Migration behavior of heavy metals in coal fly ash-derived Cu-SSZ-13 during synthesis and NH3-SCR application. (15th June 2022)

• Record Type: Journal Article
• Authors: Shi, Pengcheng; Wang, Bing; Yin, Ruiqi; Ren, Weiguo; Wang, Jiancheng; Chang, Liping; Huang, Zhanggen; Bao, Weiren; Han, Lina
• Is Part Of: Fuel. Volume 318(2022)
• Publication Date: 2022-06-15
• Subjects: Harmlessness -- Hydrothermal synthesis -- High-valued utilization -- Solid waste -- Environmental catalysis; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2022.123633
• Languages: English
• ISSNs: 0016-2361

Abstract

Graphical abstract: Highlights: SSZ-13 zeolite were synthesized using CFA via a two-step hydrothermal method. A modified BCR sequential extraction procedure was used to extract the heavy metals. Pb, Cr, and Cd remained in SSZ-13 and Hg, As, and Se migrated into the leachate. The NH3 -SCR performance of SSZ-13 is comparable to its commercial counterpart. Residual Pb, Cr, and Cd in SSZ-13 hardly release to the environment during NH3 -SCR. Abstract: The hazardous heavy metals in coal fly ash (CFA) restrict the recycling, utilization, and application of CFA and its derived products, especially for the CFA-fabricated zeolite that is applied to environmental catalysis. To clarify the migration behavior of the heavy metals during the synthesis process of target zeolite and its application, we prepared zeolite SSZ-13 using a two-step hydrothermal strategy and evaluated the migration and residual rates of the heavy metals including Hg, As, Se, Pb, Cr, and Cd in these processes. The NH3 -SCR of NO performance and its effects on the existence of heavy metals were also examined. A modified Community Bureau of Reference (BCR) sequential extraction procedure was used to extract the heavy metals. Pb, Cr, and Cd remain in the SSZ-13, while Hg, As, and Se reside in the leachate during the hydrothermal reaction. The former three elements existed mainly as residuals in zeolite SSZ-13. The latter moved to the leachates. The SSZ-13 after ion-exchanged with Cu 2+ shows high NH3 -SCR performance, and the residual minim heavy metals rarely moved into the environment, indicating a harmless utilization process. This work contributed to the harmlessness and recycling of CFA and the development of high-value CFA-derived zeolite catalysts applied to environmental catalysis.