Ceramic ozone catalytic coupling incineration ash and excess sludge recycling with ceftriaxone sodium wastewater treatment: Performance and mechanism

Abstract

Highly efficient and economic treatment of wastewater sludges and wastewater containing ceftriaxone sodium (CRO) in one way is a challenging issue in the water treatment field. Therefore, a waste-recycling strategy of reasonably manufactured ceramic ozone catalyst (COC) with low cost and high value was proposed, which solved the difficult problems of sludge and incineration ash disposal and CRO removal. In view of the complex reaction among the components, the recovery heat conversion mechanism of inorganic substances forming crystalline ceramic skeleton, heavy metals solidifying stably and forming catalytic sites, and organic substances pore-forming in the whole material composition is expounded. COC has excellent catalytic performance. Under the optimal reaction conditions, the removal rate of CRO is 97.87 %, which accords with the first-order reaction kinetic model. The free radical quenching study and electron spin resonance (ESR) analysis show that the main free radical in the COC/O3 system is •O2–. The degradation intermediates in various time periods were identified by LC-MS analysis, while the degradation and transformation ways of CRO were put forward. The excellent catalytic performance can be attributed to the synergistic effect of electronic mediator CO, CC functional group adsorption and catalytic electron transfer mechanism of MgFe2O4, MnFe2O4, Fe2O3 and TiO2. In addition, COC has excellent repeatability, stability and environmental safety. The benefits of waste recycling are obvious.