One-step synthesis of Fe-Mg oxides/hydrochar composites enhanced peroxymonosulfate activation to accelerate organics degradation in aquatic and soil systems.

Abstract

Heterogeneous catalysts for peroxymonosulfate (PMS)-based organic pollutant degradation offer economic benefits; however, efficient catalysts suitable for both aquatic and soil environments remain scarce. Here, a one-step hydrothermal method was developed to synthesize hydrochar (HC)-encapsulated iron-magnesium bimetal oxides (FeMgO/HC) for enhanced PMS activation. The FeMgO/HC+PMS system achieved 95.4 % tetracycline degradation in aqueous systems, with a rate constant over five times higher than HC/PMS system, and effectively degraded bisphenols (>80 %), which HC/PMS could not achieve. Mechanistic investigations revealed that the degradation process in the aqueous FeMgO/HC+PMS system involved both radical (•OH, SO4•-, O2•-) and non-radical (1O2) pathways, facilitated by enhanced electron transfer via the Fe(III)/Fe(II) redox cycle. In soil environment, FeMgO/HC+PMS system degraded over 90 % of bisphenol B under optimized conditions, accompanied by increases in soil organic matter content and microbial diversity. These findings confirm the environmental compatibility and practical applicability of the FeMgO/HC+PMS system.

Abstract as supplied by the indexing source. © the authors / publisher.