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Xianliang Qiao

Bio: Xianliang Qiao is an academic researcher from Dalian University of Technology. The author has contributed to research in topics: Photodegradation & Quantitative structure–activity relationship. The author has an hindex of 27, co-authored 81 publications receiving 2824 citations.


Papers
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Journal ArticleDOI
TL;DR: Nano-Co 3 O 4 /PMS was used to activate peroxymonosulfate (PMS) and degrade a model compound Acid Orange 7 (AO7).
Abstract: Nano-Co 3 O 4 was prepared by precipitation method and was successfully applied as heterogeneous catalyst to activate peroxymonosulfate (PMS) and degrade a model compound Acid Orange 7 (AO7). The catalyst exhibits spherical morphologies with minor particle agglomeration, small particle average size (20 nm) and high specific surface area (18 m 2 /g). The degradation kinetics of AO7 induced by nano-Co 3 O 4 /PMS system was investigated at both acidic and neutral pH conditions. The heterogeneous character of PMS activation with nano-Co 3 O 4 is more pronounced at neutral pH as indicated by fast degradation rate of AO7 and low dissolved Co ion. The catalyst presented a long-term stability through using the catalyst for multiple runs in the degradation of AO7. The main degradation intermediates of AO7 identified by GC/MS and LC/MS were 4-hydroxybenzenesulfonic acid, 1,2-naphthalenedione, coumarin, phthalic anhydride, phthalimide and 2-formyl-benzoic acid. Proposed degradation pathways were elucidated in light of the analyzed degradation products and frontier electron density theory.

382 citations

Journal ArticleDOI
TL;DR: The photodegradation product identification and ROS scavenging experiments indicated that the FQs underwent both direct photolysis and self-sensitized photo-oxidation via *OH and (1)O(2).
Abstract: The ubiquity of fluoroquinolone antibiotics (FQs) in surface waters urges insights into their fate in the aqueous euphotic zone. In this study, eight FQs (ciprofloxacin, danofloxacin, levofloxacin, sarafloxacin, difloxacin, enrofloxacin, gatifloxacin, and balofloxacin) were exposed to simulated sunlight, and their photodegradation was observed to follow apparent first-order kinetics. Based on the determined photolytic quantum yields, solar photodegradation half-lives for the FQs in pure water and at 45 degrees N latitude were calculated to range from 1.25 min for enrofloxacin to 58.0 min for balofloxacin, suggesting that FQs would intrinsically photodegrade fast in sunlit surface waters. However, we found freshwater and seawater constituents inhibited their photodegradation. The inhibition was further explored by a central composite design using sarafloxacin and gatifloxacin as representatives. Humic acids (HA), Fe(III), NO(3)(-), and HA-Cl(-) interaction inhibited the photodegradation, as they mainly acted as radiation filters and/or scavengers for reactive oxygen species. The photodegradation product identification and ROS scavenging experiments indicated that the FQs underwent both direct photolysis and self-sensitized photo-oxidation via *OH and (1)O(2). Piperazinyl N(4)-dealkylation was primary for N(4)-alkylated FQs, whereas decarboxylation and defluorination were comparatively important for the other FQs. These results are of importance toward the goal of assessing the persistence of FQs in surface waters.

256 citations

Journal ArticleDOI
TL;DR: The results suggest that FA with nonnegative constraints is a promising tool for source apportionment of PAHs in soils and shows reasonable explanations for PAH contributions in soils from different sites.

198 citations

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TL;DR: Toxicity analysis indicated that metal coordination did modify the toxicity of the antibiotics and that antibiotic, metal, and their complex acted primarily as concentration addition, and environmental scenario analysis demonstrated that ignoring complexation would improperly classify environmental risks of the antibiotic.

161 citations

Journal ArticleDOI
Linke Ge1, Jingwen Chen1, Xianliang Qiao1, Jing Lin1, Xiyun Cai1 
TL;DR: UV-vis photodegradation intermediates were identified by HPLC-MS/MS, and degradation pathways were proposed, which involve photoinduced hydrolysis, dechlorination, self-sensitized photo-oxidation processvia (1)O2, and chlorination, of importance toward the goal of assessing the persistence of phenicols in wastewater treatment and the environment.
Abstract: Thiamphenicol and florfenicol are two phenicol antibiotics commonly used in aquaculture. Photodegradation experiments on these phenicols were performed in aqueous solutions under irradiation of different light sources. We found under UV−vis irradiation (λ > 200 nm) they photodegraded the fastest in seawater, followed by pure water and freshwater, whereas under solar or simulated sunlight (λ > 290 nm), they photodegraded in freshwater only. The effects of Cl− (the dominant seawater constituent), humic acids (HA, main constituents in freshwater) and other water constituents on the photodegradation of the antibiotics as a function of different light sources were studied so as to interpret the light-source-dependent effects of different waters. Under UV−vis irradiation, Cl− was found to promote singlet oxygen (1O2) formation and accelerated the photodegradation of phenicols, whereas the phenicols did not photolyze under simulated solar irradiation, irrespective of Cl−. In contrast, the presence of HA inhibite...

150 citations


Cited by
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TL;DR: In this paper, the authors provide a state-of-the-art review on the development in heterogeneous catalysts including single metal, mixed metal, and nonmetal carbon catalysts for organic contaminants removal, with particular focus on peroxymonosulfate (PMS) activation.
Abstract: Sulfate radical-based advanced oxidation processes (SR-AOPs) employing heterogeneous catalysts to generate sulfate radical (SO4 −) from peroxymonosulfate (PMS) and persulfate (PS) have been extensively employed for organic contaminant removal in water. This article aims to provide a state–of–the–art review on the recent development in heterogeneous catalysts including single metal, mixed metal, and nonmetal carbon catalysts for organic contaminants removal, with particular focus on PMS activation. The hybrid heterogeneous catalyst/PMS systems integrated with other advanced oxidation technologies is also discussed. Several strategies for the identification of principal reactive radicals in SO4 −–oxidation systems are evaluated, namely (i) use of chemical probe or spin trapping agent coupled with analytical tools, and (ii) competitive kinetic approach using selective radical scavengers. The main challenges and mitigation strategies pertinent to the SR-AOPs are identified, which include (i) possible formation of oxyanions and disinfection byproducts, and (ii) dealing with sulfate produced and residual PMS. Potential future applications and research direction of SR-AOPs are proposed. These include (i) novel reactor design for heterogeneous catalytic system based on batch or continuous flow (e.g. completely mixed or plug flow) reactor configuration with catalyst recovery, and (ii) catalytic ceramic membrane incorporating SR-AOPs.

1,802 citations

Journal ArticleDOI
TL;DR: A literature review on environmental application of peroxymonosulfate (PMS) in degradation of contaminants to clarify the performance of PMS is carried out in this paper, which describes the PMS usage in remediation of environmental pollutants with focus on the different methods of activation and the effect of main operational parameters on PMS-based processes.

1,650 citations

Journal ArticleDOI
TL;DR: In this paper, the state-of-the-art progress on various heterogeneous cobalt-based catalysts for sulfate radical-based advanced oxidation processes (SR-AOPs) is reviewed.
Abstract: Recently sulfate radical-based advanced oxidation processes (SR-AOPs) attract increasing attention due to their capability and adaptability in decontamination. The couple of cobalt and peroxymonosulfate (PMS) is an efficient way to produce reactive sulfate radicals. This article reviews the state-of-the-art progress on various heterogeneous cobalt-based catalysts for PMS activation, including cobalt oxides, cobalt-ferrite and supported cobalt by diverse substrates. We summarize the intrinsic properties of these catalysts and their fundamental behaviors in PMS activation, as well as synthetic approaches. In addition, influencing factors and synergistic techniques of Co/PMS systems in organic degradation and possible environmental applications are also discussed. Finally, we propose perspectives on challenges related to cobalt-based catalysts, heterogeneous Co/PMS systems and their potential applications in practical environmental cleanup.

1,553 citations

Journal ArticleDOI
TL;DR: This Critical Review comparatively examines the activation mechanisms of peroxymonosulfate and peroxydisulfates and the formation pathways of oxidizing species and the impacts of water parameters and constituents such as pH, background organic matter, halide, phosphate, and carbonate on persulfate-driven chemistry.
Abstract: Reports that promote persulfate-based advanced oxidation process (AOP) as a viable alternative to hydrogen peroxide-based processes have been rapidly accumulating in recent water treatment literature. Various strategies to activate peroxide bonds in persulfate precursors have been proposed and the capacity to degrade a wide range of organic pollutants has been demonstrated. Compared to traditional AOPs in which hydroxyl radical serves as the main oxidant, persulfate-based AOPs have been claimed to involve different in situ generated oxidants such as sulfate radical and singlet oxygen as well as nonradical oxidation pathways. However, there exist controversial observations and interpretations around some of these claims, challenging robust scientific progress of this technology toward practical use. This Critical Review comparatively examines the activation mechanisms of peroxymonosulfate and peroxydisulfate and the formation pathways of oxidizing species. Properties of the main oxidizing species are scrutinized and the role of singlet oxygen is debated. In addition, the impacts of water parameters and constituents such as pH, background organic matter, halide, phosphate, and carbonate on persulfate-driven chemistry are discussed. The opportunity for niche applications is also presented, emphasizing the need for parallel efforts to remove currently prevalent knowledge roadblocks.

1,412 citations

Journal ArticleDOI
TL;DR: Polycyclic aromatic hydrocarbon diagnostic ratios have recently come into common use as a tool for identifying and assessing pollution emission sources and are reviewed to specify their limitations.

1,331 citations