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[Display omitted] • Exceptional CIP degradation efficiency (>95 %) and minimal Co2+ leaching (<0.32 mg/L) were achieved. • The unique heterogeneous interior structure enhanced charge transfer and metal cycling. • SO 4 •− and 1O 2 were the primary reactive species responsible for CIP degradation. • Two degradation paths and the overall decrease of ecotoxicity after degradation were deduced. A dual-metal organic framework (MOF) heterostructure, ZIF-67@MIL-100(Fe), was successfully constructed and employed in a photo-assisted peroxymonosulfate (PMS) activation system for ciprofloxacin (CIP) degradation. The outer wrapping structure of MIL-100(Fe) effectively stabilizes ZIF-67, resulting in minimal Co2+ leaching (<0.32 mg/L). For CIP degradation (10 mg/L), the ZIF-67@MIL-100(Fe) exhibited superior catalytic performance (>95 %) with a rate constant of 0.0438 min−1, attributed to the synergistic interaction between the MIL-100(Fe) shell and ZIF-67 core. It was characterized to be more favorable for light absorption, charge separation, and migration than individual components, fostering redox cycles of Co(III)/Co(II) and Fe(III)/Fe(II). This photo-assisted PMS activation process involved both free radical and non-free radical pathways, with SO 4 •− and 1O 2 playing dominant roles in CIP degradation. Based on seven measured intermediates, two degradation pathways were derived: oxidation of the piperazine ring and hydroxylation. Toxicity Evaluation Software Tool (T.E.S.T.) analysis indicated an overall decrease in ecological toxicity following CIP degradation. Furthermore, the composite exhibited robust stability in five cyclic experiments and real aquatic environments, underscoring the photo-assisted ZIF-67@MIL-100(Fe) activated PMS process as a promising and environmentally friendly approach for eliminating antibiotics from contaminated water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Magnetic activated carbon ballasted coagulation (MAC-BC) process was proposed. • Superior coagulation performance and enhanced antibiotic removal were achieved. • Response of floc properties to MAC ballasting was characterized in real-time. • MAC played a dominant role in antibiotic removal rather than the coagulant. • The mechanism of MAC ballasting to enhance antibiotic removal was deciphered. Removal of antibiotics from wastewater is extremely important for the reduction of antibiotic resistance-related risk and safe water reuse. Coagulation is a promising approach for this purpose, but its practical implementation requires further upgrades in coagulation performances and antibiotics targeting. Here, the magnetic activated carbon ballasted coagulation (MAC-BC) process was proposed to enhance the coagulation process and antibiotic sulfamethoxazole (SMX) removal. Response surface curves indicated that MAC played a dominant role in SMX removal rather than coagulant. The MAC ballasting promoted the removal of DOC and SMX in the coagulation process by 1.4 and 1.6 times, which was attributed to hydrogen bonding interaction, π-π electro-donor-accepter interaction, and surface complexation introduced by COOH/C–O, C C, and Fe–O/Al–O in the MAC flocs, respectively. MAC could serve as nuclei and readily bound to the hydrolyzed Al species, resulting in the formation of larger Al-species-induced primary clusters. The ratio of OH/Al on the surface of MAC-BC flocs was higher than that of the flocs generated in the single coagulation process. The higher binding ability with MAC addition facilitated the aggregation of primary clusters and increased the floc size by 1.3 times, which further accelerated floc settling and separation. The multiple functions of MAC ballasting enhanced the coagulation process and promoted SMX removal. This study opens a new avenue to upgrade traditional coagulation and adsorption processes. [ABSTRACT FROM AUTHOR]

[Display omitted] • A pumice-based solid visible light responsive photocatalyst PS@rGO@MnO 2 was successfully synthesized. • PS@rGO@MnO 2 has an effective removal effect on ciprofloxacin in natural surface water under sunlight. • The degradation mechanism and transformation pathway of ciprofloxacin, as well as the ecotoxicity of intermediate products were proposed. • PS@rGO@MnO 2 material has good stability and convenient recycling. The agglomeration and recycling of nano-photocatalytic materials are still a big problem restricting the practical application of photocatalytic technology. Natural porous pumice with adsorption capacity provides an innovative approach to this challenge. Herein, the pumice supported reduced graphene oxide and MnO 2 (PS@rGO@MnO 2) was designed as a visible-light-driven solid photocatalyst. The PS@rGO@MnO 2 possessed good photocatalytic performance, and the removal rate of ciprofloxacin (CFX) reached 80.00% with simulated solar irradiation for 6 h, and the degradation rate constant was 4.2 times that of blank pumice. The degradation rates of CFX in secondary effluent, lake water, and river water can reach 62.15%, 68.33%, and 67.63%, respectively. Hole (h+) and superoxide radical (O 2 −) are the main reactive oxygen species. The material test results revealed that the enhanced photocatalytic performance of PS@rGO@MnO 2 was due to the improvement of light utilization rate, the reduction of electron-hole pair recombination rate, and the improvement of charge separation efficiency and transfer efficiency. ECOSAR model predictions indicate that CFX can effectively reduce toxicity in photocatalytic reactions. The removal performance of actual natural water verified that the material was of great practical application potential. [ABSTRACT FROM AUTHOR]