Pesticide abatement using environmentally friendly nano zero valent particles as photo-Fenton catalyst

Abstract

Nano-zero valent iron particles (NZVI) have been used for the pesticide pirimicarb degradation under simulated solar radiation. These particles have been synthesized by extracts from agro-industrial residues, namely vineyard and blueberry pruning, black tea and algae, so they can be labelled as “green-NZVI”. The physico-chemical properties of these green-NZVI were compared to those of NZVI synthesized with NaBH4. The usage of agro-industrial residues as reducing agent not only provided better performant NZVI but also evade the usage of harmful reagents. Indeed, this process is not only within circular economy, and environmentally friendly, but also defeats the degradation performance of the widely reported photo-Fenton process with Fe2+ catalyst. 96.5 % pirimicarb degradation was achieved under simulated solar radiation within 15 min with 0.08 mM H2O2 and 0.16 mM NZVI synthesized with black tea extract. Further, the developed process was optimized in terms of reagents concentration and natural antioxidant extract used for NZVI synthesis, which demonstrated a strong effect on pirimicarb degradation due to the differences on natural phenolic compounds present on them. The pirimicarb degradation pathway was analysed, confirming the successful pesticide degradation. In terms of H2O2 concentration, it can be reduced by its sequential addition in time. Under optimal conditions, even real effluents can be successfully degraded.