Using chicken manure as raw material to prepare activated carbon as a dispersant, a novel biochar-loaded nano-zerovalent iron composite (nZVI@CMBC) was developed and applied to remove hexavalent chromium, i.e., Cr(VI), in wastewater. The dispersion of nano-zerovalent iron (nZVI) particles on the surface of chicken manure–derived biochar (CMBC) successfully inhibited the aggregation of magnetic iron particles and effectively reduced the size of nZVI particles. The results demonstrated that under acidic conditions, the removal efficiency of Cr(VI) by the nZVI@CMBC composite could reach 124.12 mg g−1. The pseudosecond-order kinetic model had a good agreement with the adsorption kinetics of the nZVI@CMBC composite, implying that the adsorption of Cr(VI) is based on the multi-layer chemical adsorption. Therefore, this study provides a new clue and strategy for removing Cr(VI) in wastewater.

Sulfate-radical-based wastewater treatment has received great interest due to its high-level efficiency. However, the preparation of stable and recyclable nanocatalysts remains a challenge. Herein, a highly efficient catalyst (FeCo/SC) for persulfate activation is successfully synthesized via dispersing S and Fe into carbon skeletons derived from ZIF-67. After the introduction of S, FeCo/SC exhibited excellent catalytic performance. With the action of SO 4 −• , Fe(VI), and 1 O 2 , the degradation efficiency of carbamazepine (CBZ) (10 mg L −1 ) could be up to 97.9 ± 2% within 10 min. The results showed that the larger surface area after S doping decreases the electron transfer resistance. The S 0 /S 2− is beneficial for promoting the Fe(III)-to-Fe(II) and Co(III)-to-Co(II) conversion cycle. Moreover, the liquid chromatograph-mass spectrometer (LC-MS), density functional theory (DFT), and ecological structure−activity relationships (ECOSAR) revealed the possible degradation pathway of CBZ, which was a toxicity attenuation process. In consequence, this work offers an innovative scheme for researching the effect of trace S-doped bimetallic oxide nanoparticles on PDS heterogeneous catalytic systems.