Effective green treatment of sewage sludge from Fenton reactions: Utilizing MoS ₂ for sustainable resource recovery

Abstract

Effectively managing sewage sludge from Fenton reactions in an eco-friendly way is vital for Fenton technology's viability in pollution treatment. This study focuses on sewage sludge across various treatment stages, including generation, concentration, dehydration, and landfill, and employs chemical composite MoS₂ to facilitate green resource utilization of all types of sludge. MoS₂, with exposed Mo⁴⁺ and low-coordination sulfur, enhances iron cycling and creates an acidic microenvironment on the sludge surface. The MoS₂-modified iron sludge exhibits outstanding (>95%) phenol and pollutant degradation in hydrogen peroxide and peroxymonosulfate-based Fenton systems, unlike unmodified sludge. This modified sludge maintains excellent Fenton activity in various water conditions and with multiple anions, allowing extended phenol degradation for over 14 d. Notably, the generated chemical oxygen demand (COD) in sludge modification process can be efficiently eliminated through the Fenton reaction, ensuring effluent COD compliance and enabling eco-friendly sewage sludge resource utilization.