Showing papers by "Deli Wu published in 2018"
TL;DR: In this paper, the surface Fe(II) species activated persulfate (PS) to produce OHads and SO4 −ads, controlled by surface reaction and diffusion, whereas OHfree and SO 4 −free diffusing from the FeS surface were mainly responsible for PS degradation.
209 citations
TL;DR: Fe-g-C3N4-PMS had a wide effective pH range, and its reactivity was nearly independent of natural illumination, and quenching experiments revealed that nonradical oxidation contributed to the observed degradation.
132 citations
TL;DR: In this paper, a sulfide-modified nano-scale zero-valent iron (S-nZVI) was synthesized and employed for the removal of aqueous As(III).
Abstract: Sulfide-modified nano-scale zero-valent iron (S-nZVI) was synthesized and employed for the removal of aqueous As(III). The structure and removal performance of S-nZVI was investigated and compared with that of pristine nZVI. S-nZVI has an optimal As removal capacity of 240 mg/g, which is much higher than that of nZVI. The sulfidation of nZVI also enhanced the As(III) removal rate, and the enhancement largely depended on the S/Fe molar ratio. The optimum pH for As(III) removal with S-nZVI was in a broad range from 3 to 8. Transmission electron microscopy (TEM) with energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM) with EDS, and X-ray photoelectron spectroscopy (XPS) were employed to characterize the S-nZVI before and after reacting with As(III). The results demonstrated that S-nZVI had a unique core–shell structure. Sulfur was incorporated into the shell of S-nZVI, and the thickness of the surface layer increased from 5 nm to approximately 30 nm, which suggested that more As(II...
75 citations
TL;DR: In this article, a combination of pyrite, an abundant mineral used as a slow-release source of iron, and peroxymonosulfate (PMS) was used to degrade extremely recalcitrant 1,4-dioxane.
65 citations
TL;DR: In this paper, siderite was used to activate peroxydisulfate (PDS) and peroxymonosulfate(PMS) with phenol as a model contaminant.
Abstract: Ferrous ions (Fe2+) rapidly activate persulfates to produce sulfate radicals. However, the high reactivity of Fe2+ toward sulfate radicals means that they are easily scavenged, which reduces the stoichiometric efficiency of persulfates. To improve the stoichiometric efficiency, siderite was used to activate peroxydisulfate (PDS) and peroxymonosulfate (PMS), with phenol as a model contaminant. Near-100% degradation of phenol was achieved by siderite-activated PDS or PMS. In contrast, only 34% and 25% of the phenol was degraded by Fe2+- and nanoscale-magnetite-activated persulfates, respectively. The stoichiometric efficiencies of PMS and PDS activated by siderite were more than 4.4 and 3.6 times higher, respectively, than those activated by Fe2+. Electron paramagnetic resonance recorded both sulfate radicals and hydroxyl radicals. The effects of pH, iron dissolution, and scavenging were characterized, and the results indicated that siderite mainly activated persulfates by acting as a source of Fe2+ and tha...
63 citations
TL;DR: The quenching experiment and electron spin resonance (ESR) spectroscopy demonstrated that the dominant radical species in H2O2/PDS-based AOPs via pyrite at a pH of 4 were OH and OH/SO4-, respectively, thus causing different degradation pathways of ACT.
36 citations
TL;DR: In this article, three GR/Cu(II) composites were synthesized and used to activate dioxygen under weakly acidic conditions, and the change in the mechanism caused by three interlayer anions, CO32−, SO42−, and Cl−, was discussed for the first time.
13 citations
TL;DR: Results suggest that the activation of PMS by all the supported Pd NPs proceeded via a radical mechanism, critical to the development of efficient composite catalysts and the scientific understanding of observing different active species produced by Pd-catalyzed PMS.
6 citations
TL;DR: This novel catalytic ozonation can maintain high mineralization efficiency in a wide range of pH (3-10), which was ascribed to the synergistic catalytic performance of various oxides.
1 citations
Patent•
11 Oct 2018
TL;DR: In this article, a method for synchronously removing a complex heavy metal and an organic substance from waste water with a magnetic iron-based material comprises four steps including an anaerobic reaction, an incubation reaction, a aerobic reaction, and a magnetic separation reaction.
Abstract: A method for synchronously removing a complex heavy metal and an organic substance from waste water with a magnetic iron-based material comprises four steps including an anaerobic reaction, an incubation reaction, an aerobic reaction, and a magnetic separation reaction. Reductive decomplexation of a complex heavy metal is achieved by utilizing the reducibility of an iron-based material under anaerobic conditions, and a catalyst having a function of activating molecular oxygen is formed in-situ simultaneously. Molecular oxygen is catalyzed by an iron-based catalyst under aerobic conditions to form a species with strong oxidizability, and an organic contaminant is oxidized and degraded. The removal of contaminants is enhanced through magnetic separation. The idea of treating waste with waste achieves eco-friendly oxidation, shortens treatment processes, improves treatment efficiency, reduces economic costs, and promotes the application of technology in industry.