Abstract

δ-MnO 2 coatings on clay substrates tend to be poorer in crystallinity as compared with their discrete counterparts, which may be of environmental significance for adsorption and oxidation of contaminants. Discrete δ-MnO 2 particles and three δ-MnO 2-coated montmorillonite complexes with varying MnO 2 loadings (4.8–34.9%) were synthesized, and oxidative decolorization of methylene blue (MB) by the synthetic materials was investigated in batch systems. Results showed that oxidative decolorization of MB increased with increasing loading of Mn-oxide coatings, whereas oxidation capacity of the coatings, on the basis of unit mass of MnO 2, tended to decrease. Initial reaction rate of MB oxidation by both δ-MnO 2 coatings and their discrete counterpart increased linearly with increasing Mn-oxide loadings, but the rate of the former was higher than that of the latter. An increase in humic acid concentration displayed a progressively enhanced promotive effect on MB decolorization, whereas the promotive effect was greatly suppressed at lower pH.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.