Novel cryptomelane nanosheets for the superior catalytic combustion of oxygenated volatile organic compounds

Minh Tuan Nguyen Dinh; Chinh Chien Nguyen; Manh Duy Phan; Minh Khoa Duong; Phuc Hoang Duy Nguyen; Christine Lancelot; Dinh Lam Nguyen

doi:10.1016/j.jhazmat.2021.126111

Novel cryptomelane nanosheets for the superior catalytic combustion of oxygenated volatile organic compounds

J Hazard Mater. 2021 Sep 5:417:126111. doi: 10.1016/j.jhazmat.2021.126111. Epub 2021 May 14.

Authors

Minh Tuan Nguyen Dinh¹, Chinh Chien Nguyen², Manh Duy Phan³, Minh Khoa Duong³, Phuc Hoang Duy Nguyen⁴, Christine Lancelot⁵, Dinh Lam Nguyen³

Affiliations

¹ The University of Da-Nang, University of Science and Technology, 54, Nguyen Luong Bang, Da Nang, Viet Nam. Electronic address: ndmtuan@dut.udn.vn.
² Institute of Research and Development, Duy Tan University, Da Nang 50000, Viet Nam; Faculty of Environmental and Chemical Engineering, Duy Tan University, Da Nang 50000, Viet Nam.
³ The University of Da-Nang, University of Science and Technology, 54, Nguyen Luong Bang, Da Nang, Viet Nam.
⁴ Institute of Chemical Technology-Vietnam Academy of Science and Technology, Ho Chi Minh City, Viet Nam.
⁵ Univ. Lille, CNRS, Centrale Lille, ENSCL, Univ. Artois, UMR 8181 - UCCS - Unité de Catalyse et Chimie du Solide, F-59000 Lille, France.

PMID: 34020350
DOI: 10.1016/j.jhazmat.2021.126111

Abstract

This work offers a novel pathway to prepare cryptomelane manganese oxides nanosheets as an superior catalyst for the catalytic combustion of oxygenated volatile organic compounds. The tunnel cryptomelane manganese oxides nanosheets were prepared from layered birnessite via simultaneously tuning pH and molar ratio (R_OK) of the redox-precipitation between oxalic acid and KMnO₄. Thus, few-layered cryptomelane nanosheets possessing the most predominantly exposed (211) facet are generated at low pH (5.2-5.6), which intensifies the surface area of thin crystal cryptomelane nanosheets up to 177 m²g^-1 and weakens Mn-O bonds. Moreover, high R_OK results in low manganese average oxidation state (AOS), greater oxygen vacancies and better low-temperature reduction and oxygen mobility. Such features significantly maneuver the catalytic activity of the cryptomelane nanosheets catalysts for the complete oxidation of oxygenated volatile organic compound (e.g., 2-propanol, acetone) at low temperature (170-230 °C). Moreover, the catalysts show high stability for 48 h. The presented catalyst discloses an avenue to address current obstacles in the catalytic oxidation of volatile organic compounds.

Keywords: 2-propanol; Acetone; Catalytic combustion; Cryptomelane; Nanosheets; Oxygen vacancies.