Publications by authors named "Jianshe Liu"

120 Publications

Performance of UV/acetylacetone process for saline dye wastewater treatment: Kinetics and mechanism.

J Hazard Mater 2021 03 5;406:124774. Epub 2020 Dec 5.

Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, Shanghai 200241, China; State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China.

Futility of traditional advanced oxidation processes (AOPs) in saline wastewater treatment has stimulated the quest for novel "halotolerant" chemical oxidation technology. Acetylacetone (AA) has proven to be a potent photo-activator in the degradation of dyes, but the applicability of UV/AA for saline wastewater treatment needs to be verified. In this study, degradation of crystal violet (CV) was investigated in the UV/AA system in the presence of various concentrations of exogenic Cl or Br. The results reveal that degradation, mineralization and even accumulation of adsorbable organic halides (AOX) were not significantly affected by the addition of Cl or Br. Rates of CV degradation were enhanced by elevating either AA dosage or solution acidity. An apparent kinetic rate equation was developed as r = -d[CV]/dt = k[CV][AA] = (7.34 × 10 mM min) × [CV] [AA]. In terms of results of radical quenching experiments, direct electron/energy transfer is considered as the major reaction mechanism, while either singlet oxygen or triplet state ((AA)*) might be involved. Based on identification of degradation byproducts, a possible degradation pathway of CV in the UV/AA system is proposed.
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http://dx.doi.org/10.1016/j.jhazmat.2020.124774DOI Listing
March 2021

BiOBr/Ag/AgBr heterojunctions decorated carbon fiber cloth with broad-spectral photoresponse as filter-membrane-shaped photocatalyst for the efficient purification of flowing wastewater.

J Colloid Interface Sci 2021 Apr 9;587:633-643. Epub 2020 Nov 9.

College of Materials Science and Engineering, Donghua University, Shanghai 201620, China. Electronic address:

The development of recyclable photocatalysts with broad-spectral photoresponse has drawn much attention for the practical application in flowing wastewater treatment. Herein, we have reported the construction of BiOBr/Ag/AgBr junctions on carbon fiber cloth (CFC) as broad-spectral-response filter-membrane-shaped photocatalyst that is efficient and easily recyclable. With CFC as the substrate, BiOBr nanosheets (diameter: 0.5-1 μm) were firstly synthesized by a hydrothermal method, and then Ag/AgBr nanoparticles (size: 100-300 nm) were prepared on the surface of CFC/BiOBr by using a chemical bath deposition route. CFC/BiOBr/Ag/AgBr presents superior flexibility and wide UV-Vis-NIR photoabsorption (from 200 to 1000 nm). Under visible light irradiation, CFC/BiOBr/Ag/AgBr (area: 4 × 4 cm) can remove 99.8% rhodamine B (RhB), 99.0% acid orange 7 (AO7), and 93.0% tetracycline (TC) after 120 min, better than CFC/BiOBr (95.4% RhB, 55.0% AO7 and 91.2% TC). Interestingly, when CFC/BiOBr/Ag/AgBr is served as a filter-membrane in a photoreactor to purify the flowing sewage (RhB, rate: ~1.5 L h), the degradation rate of RhB goes up to 90.0% after ten filtering grades. Therefore, CFC/BiOBr/Ag/AgBr has great potential to purify the flowing wastewater as a novel filter-membrane-shaped photocatalyst.
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http://dx.doi.org/10.1016/j.jcis.2020.11.020DOI Listing
April 2021

Spatial and seasonal variations and risk assessment for heavy metals in surface sediments of the largest river-embedded reservoir in China.

Environ Sci Pollut Res Int 2020 Oct 27;27(28):35556-35566. Epub 2020 Jun 27.

Shanghai National Engineering Research Center of Urban Water Resources Co., Ltd., Shanghai, 200082, China.

The sediment acts as not only sink but also source of heavy metals in aquatic environment, which may cause the endogenous pollution in drinking water reservoirs. In this work, we collected the surface sediments from Qingcaosha Reservoir, the largest river-embedded reservoir in China, and investigated the spatial distribution, risk, and sources of heavy metals in four seasons. Significant spatial and seasonal heterogeneity could be found in the distribution of five heavy metals (Cr, Cu, Mn, Zn, and Ni) in the surface sediments. The highest concentrations of the five metals were detected in the sediments from the reservoir downstream, especially in summer and next spring. The geo-accumulation index (I) and enrichment factor (EF) suggest that the sediment pollution caused by single metal was heavier in summer than in other seasons. Also, the Nemerow pollution index (PI) manifests that the synergetic pollution induced by five metals was most serious in summer, followed by next spring. However, the potential ecological risk index (PERI) indicates that none of these metals caused potential ecological risk in four seasons. Comprehensive analysis demonstrates that the sediment pollution gradually increased from autumn to winter and then to next spring. Principal component analysis shows that the main pollution source of five heavy metals may come from industrial wastewater and domestic sewage, which was almost independent of seasons. This work can provide data support for the subsequent seasonal optimization of drinking water quality and reservoir management.
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http://dx.doi.org/10.1007/s11356-020-09868-wDOI Listing
October 2020

The enhanced degradation and detoxification of chlortetracycline by Chlamydomonas reinhardtii.

Ecotoxicol Environ Saf 2020 Jun 4;196:110552. Epub 2020 Apr 4.

Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China. Electronic address:

Nowadays, numerous studies have focused on the newly developed technologies for the thorough removal of tetracyclines (TCs). However, it is often ignored that the parent TCs have limited stability in aquatic environments. Thus, this study selected green alga Chlamydomonas reinhardtii with high chlorophyll content to rapidly degrade chlortetracycline (CTC) into products with low toxicity. As the results shown, the half-life times of CTC (1 × 10 mol/L) decreased from 10.35 h to 2.55 h by the presence of C. reinhardtii at 24±1 °C with 12/12 h dark/light cycle. The main transformation products were iso-chlortetracycline (ICTC), 4-epi-iso-chlortetracycline (EICTC), and other degradation products with lower molecular weight. The toxicity evaluation shows that the negative effects of CTC on growth rate and soluble protein content of green algae were significantly alleviated after the enhanced degradation treatment, while the generation of reactive oxygen species (ROS) and antioxidant response in algal cells returned to normal levels. The chlorophyll of algae played an important role of photosensitizer, which catalyzed the photo-induced electron/energy transfer of CTC degradation. The ROS generation of algae also was also inseparable from the enhanced degradation of CTC, especially when the chlorophyll was damaged at the high CTC concentration. Based on these results, we can better select suitable algal species to further strengthen the degradation of antibiotics and effectively reduce the environmental risk of CTC in aqueous system.
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http://dx.doi.org/10.1016/j.ecoenv.2020.110552DOI Listing
June 2020

Deciphering the mechanism of carbon sources inhibiting recolorization in the removal of refractory dye: Based on an untargeted LC-MS metabolomics approach.

Bioresour Technol 2020 Jul 24;307:123248. Epub 2020 Mar 24.

Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.

In this study, the biological decolorization of reactive black 5 (RB5) by Klebsiella sp. KL-1 in yeast extract (YE) medium was captured the recolorization after exposure to O, which induced a 15.82% reduction in decolorization efficiency. Similar result was also observed in YE + lactose medium, but not in YE + glucose/xylose media (groups YE + Glu/Xyl). Through biodegradation studies, several degradation intermediates without quinoid structure were produced in groups YE + Glu/Xyl and differential degradation pathways were deduced in diverse groups. Metabolomics analysis revealed significant variations in up-/down-regulated metabolites using RB5 and different carbon sources. Moreover, the underlying mechanism of recolorization inhibition was proposed. Elevated reducing power associated with variable metabolites (2-hydroxyhexadecanoic acid, 9(R)-HODE cholesteryl ester, linoleamide, oleamide) rendered additional reductive cleavage of C-N bond on naphthalene ring. This study provided a new orientation to inhibit recolorization and deepened the understanding of the molecular mechanism of carbon sources inhibiting recolorization in the removal of refractory dyes.
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http://dx.doi.org/10.1016/j.biortech.2020.123248DOI Listing
July 2020

Construction of TiO/AgPO nanojunctions on carbon fiber cloth for photocatalytically removing various organic pollutants in static or flowing wastewater.

J Colloid Interface Sci 2020 Jul 13;571:213-221. Epub 2020 Mar 13.

Department of Interventional and Vascular Surgery, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, China; College of Materials Science and Engineering, Donghua University, Shanghai 201620, China. Electronic address:

Plenty of power-shaped semiconductor nanomaterials have been used to photocatalytically degrade various pollutant wastewater in beakers, but they are difficult to be applied in the practical wastewater that is flowing in river or pipeline. Thus, the key to photocatalytically degrading the flowing wastewater is to develop flexible large-scale filter-membrane with high photocatalytic activity. To address the issue, with carbon fiber cloth (CFC) as the porous substrate and TiO/AgPO as ultraviolet/visible (UV/Vis) responsed components, we reported the in-situ growth of TiO/AgPO nanojunctions on CFC as filter-membrane-shaped photocatalyst. The resulting CFC/TiO/AgPO is composed of CFC whose surface is decorated with TiO nanorods (length: 1 ± 0.5 μm, diameter: 150 ± 50 nm) and AgPO nanoparticles (diameter: 20-100 nm). CFC/TiO/AgPO displays a broad absorption region with two edges (~410 and ~510 nm), owing to the bandgaps of TiO and AgPO. Under Vis or UV-Vis light illumination, CFC/TiO/AgPO (4 × 4 cm) can efficiently degrade more phenol (80.6%/89.4%), tetracycline (TC, 91.7%/94.2%), rhodamine B (RhB, 98.4%/99.5%) and acid orange 7 (AO7, 97.6%/98.3%) in the beaker than CFC/TiO or CFC/AgPO. Especially, CFC/TiO/AgPO (diameter: ~10 cm) as the filter-membrane was used to construct multiple device for degrading the flowing RhB wastewater. The removal efficiency of RhB increases from 19.6% at the 1st pool to 96.8% at the 8th pool. Therefore, this study brings some insights for purifying organic pollutants in static or flowing wastewater by using filter-membrane-shaped photocatalysts.
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http://dx.doi.org/10.1016/j.jcis.2020.03.049DOI Listing
July 2020

The key factors and removal mechanisms of sulfadimethoxazole and oxytetracycline by coagulation.

Environ Sci Pollut Res Int 2020 May 28;27(14):16167-16176. Epub 2020 Feb 28.

Natural and Built Environments Research Centre, School of Natural and Built Environments, University of South Australia, Adelaide, SA, 5095, Australia.

The effects of coagulant dosage, alkalinity, turbidity, ionic strength, and dissolved organic matter (DOM) on the removal of sulfadimethoxazole (SMZ) and oxytetracycline (OTC) by coagulation were studied and the reaction mechanisms of the coagulation process were revealed in this research. From our results, alkalinity, turbidity, ionic strength, and DOM had different effects on the removal of antibiotics. The SMZ and OTC removals were improved with increase in poly-aluminum chloride (PACl) dosage, whereas the turbidity had less influence on the removal of SMZ and OTC because the adsorption of SMZ and OTC to kaolin was low, confirmed by a control when no PACl added. The hydrolysate of PACl played a more important role than turbidity in SMZ and OTC removals. The SMZ and OTC removals were significantly increased with the increase in alkalinity, which provided a suitable condition in situ for coagulant to form more optimal species of hydrolysate. The ionic strength, which was adjusted by NaNO, also had a positive effect on the removal of SMZ but no obvious effect on the OTC removal. Furthermore, DOM had a higher effect on the removal of SMZ than that of OTC. In another word, if a water plant wants to improve the removal of SMZ and OTC by coagulation unit, PACl hydrolysate, alkalinity, and DOM are the three key factors to be considered primarily. Moreover, an experiment for the recovery of antibiotics from the flocs was done and the results showed that OTC and SMZ were removed by different mechanisms. The OTC was removed via complexation formed through the reaction between OTC and coagulant while the SMZ was removed through the pathway of adsorption and inter-particle bridging to the surface of coagulant hydrolysate.
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http://dx.doi.org/10.1007/s11356-019-06884-3DOI Listing
May 2020

Is addition of reductive metals (Mo, W) a panacea for accelerating transition metals-mediated peroxymonosulfate activation?

J Hazard Mater 2020 03 16;386:121877. Epub 2019 Dec 16.

State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.

The interaction of reductive metal ions and peroxymonosulfate (PMS) is necessary for the generation of sulfate radials (SO), however, this process is greatly restrained by the sluggish reduction of high-valent metal ions. Here we report that commercially available reductive metal (Mo or W) powders are capable of unlocking this kinetic constraint. The reduction of Fe(III) to Fe(II), decomposition of PMS, and degradation/mineralization of 4-chlorophenol (4-CP) are all accelerated in the Mo/Fe/PMS process at a very low Fe/PMS ratio (Fe/PMS = 1/10). In such an accelerated system, common adverse effects of natural water constituents such as chloride and humic acid are largely mitigated. According to the fluorescence measurement and scavenging tests, sulfate and hydroxyl radicals dominate in Mo/Fe/PMS process. The addition of Mo or W is further confirmed to favor Cu/PMS process, but this is not the case for other metal ions (Mn, Ni, Ce and Co). Reductive zero-valence and four-valence active sites (Mo and Mo; W and W) play key roles in overall redox reaction. Overall, our present work provides an alternative route for expediting redox cycling of transition metals in advanced oxidation processes, without useless consumption of PMS and increase of total organic carbon.
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http://dx.doi.org/10.1016/j.jhazmat.2019.121877DOI Listing
March 2020

Co-metabolic degradation of refractory dye: A metagenomic and metaproteomic study.

Environ Pollut 2020 Jan 23;256:113456. Epub 2019 Oct 23.

Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China.

Fructose was utilized as an additional co-substrate to systematically investigate the molecular mechanism of its boosting effect for the degradation of refractory dye reactive black 5 (RB5) by a natural bacterial flora DDMZ1. A decolorizing rate of 98% was measured for sample YE + FRU(200) (with 3 g/L fructose additionally to yeast extract medium, 10% (v/v) inoculation size of flora DDMZ1, 200 mg/L RB5) after 48 h. This result was 21% and 77%, respectively, higher than those of samples with only yeast extract or only fructose. Fructose was found to significantly stimulated both intracellular and extracellular azoreductase secretion causing enhanced activity. Metagenomic sequencing technology was used to analyze the functional potential of genes. A label-free quantitative proteomic approach further confirmed the encoding of functional proteins by the candidate genes. Subsequently, the molecular mechanism of RB5 degradation by candidate genes and functional proteins of the dominant species were proposed. This study provides important perspectives to the molecular mechanism of co-metabolic degradation of refractory pollutants by a natural bacterial flora.
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http://dx.doi.org/10.1016/j.envpol.2019.113456DOI Listing
January 2020

Construction of titanium dioxide/cadmium sulfide heterojunction on carbon fibers as weavable photocatalyst for eliminating various contaminants.

J Colloid Interface Sci 2020 Mar 30;561:307-317. Epub 2019 Oct 30.

State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China. Electronic address:

Semiconductor heterojunction powders have exhibited the enhanced photocatalytic activities, but their practical applications have been limited due to their poor recycling performance from flowing wastewater. To solve these problems, with carbon fibers (CFs) as the fixing substrate, we constructed TiO/CdS heterojunction as a model on CF surface by utilizing a hydrothermal-chemical bath deposition method. CFs/TiO/CdS bundles display a wide photoabsorption with two photoabsorption edges (~410 and 520 nm). Furthermore, CFs/TiO/CdS bundles can be weaved into macroscopical cloth (such as weight: 0.1 g, area: 4 × 4 cm) which have considerable photocurrent density of 5.75 × 10 A/cm. Under visible light irradiation (λ > 400 nm), macroscopic CFs/TiO/CdS cloth can degrade 95.44% methylene blue (MB), 64.95% acid orange 7 (AO7), 91.37% tetracycline hydrochloride (TC) and remove 90.70% hexavalent chromium (Cr(VI)) after 120 min, higher than those by CFs/CdS (43.42% MB, 37.42% AO7, 31.76% TC and 30.45% Cr(VI)) or CFs/TiO (12.84% MB, 10.48% AO7, 11.85% TC and 15.58% Cr(VI)). Thus, CFs/TiO/CdS can act as a weavable and efficient photocatalyst for eliminating various pollutants from wastewater.
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http://dx.doi.org/10.1016/j.jcis.2019.10.105DOI Listing
March 2020

Facile Fabrication of Flower-Like BiOI/BiOCOOH p-n Heterojunctions for Highly Efficient Visible-Light-Driven Photocatalytic Removal of Harmful Antibiotics.

Nanomaterials (Basel) 2019 Nov 6;9(11). Epub 2019 Nov 6.

State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China.

Novel heterojunction photocatalysts with remarkable photocatalytic capabilities and durability for degrading recalcitrant contaminants are extremely desired; however, their development still remains quite challenging. In this study, a series of flower-like BiOI/BiOCOOH p-n heterojunctions were fabricated via a controlled in situ anion-exchange process. During the process, BiOI formation and even deposition on BiOCOOH microspheres with tight interfacial contact were realized. As expected, BiOI/BiOCOOH heterojunctions revealed remarkable enhancements in photocatalytic antibiotic degradation capacities under visible light irradiation compared with pristine BiOI and BiOCOOH. The best-performing BiOI/BiOCOOH heterojunction (i.e., IBOCH-2) showed much improved photocatalytic CIP degradation efficiency of approximately 81- and 3.9-fold greater than those of bare BiOI and BiOCOOH, respectively. The eminent photocatalytic performances were due not only to the enhanced capability in harvesting photon energies in visible light regions, but also the accelerated separation of electrons and holes boosted by the p-n heterojunction. Active species trapping tests demonstrated that superoxide free radicals (•O) and photo-generated holes (h) were major active species for CIP degradation. Recycling experiments verified the good durability of BIBO-2 over four runs. The facile in situ synthesis route and excellent performance endow flower-like BiOI/BiOCOOH heterojunctions with a promising potential for actual environmental remediation.
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http://dx.doi.org/10.3390/nano9111571DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6915482PMC
November 2019

Sugar sources as Co-substrates promoting the degradation of refractory dye: A comparative study.

Ecotoxicol Environ Saf 2019 Nov 3;184:109613. Epub 2019 Sep 3.

Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, PR China; Institute of Biosciences, Freiberg University of Mining and Technology, Freiberg, 09599, Germany.

Four sugar sources were used as co-substrates to promote the degradation of a selected refractory dye reactive black 5 (RB5) by the natural bacterial flora DDMZ1. The boosting performance of the four sugar sources on RB5 decolorization ranked as: fructose > sucrose > glucose > glucose + fructose. Kinetic results of these four co-metabolism systems agreed well with a first-order kinetic model. Four sugar sources stimulated the extracellular azoreductase secretion causing enhanced enzyme activity. An increased formation of low molecular weight intermediates was caused by the addition of sugar sources. The toxicity of RB5 degradation products was significantly reduced in the presence of sugar sources. The bacterial community structure differed remarkably as a result of sugar sources addition. For a fructose addition, a considerably enriched population of the functional species Burkholderia-Paraburkholderia and Klebsiella was noted. The results enlarge our knowledge of the microkinetic and microbiological mechanisms of co-metabolic degradation of refractory pollutants.
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http://dx.doi.org/10.1016/j.ecoenv.2019.109613DOI Listing
November 2019

An often-overestimated adverse effect of halides in heat/persulfate-based degradation of wastewater contaminants.

Environ Int 2019 09 21;130:104918. Epub 2019 Jun 21.

State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.

Halides (X) in the industrial wastewater are usually thought to adversely affect the degradation kinetics and mineralization rates in several SO-based advanced oxidation processes. However, their unfavorable effects might be overestimated, particularly the heat/persulfate (PS) system as tested in the present study. Here the degradation of phenol, benzoic acid, coumarin and acid orange 7 (AO7) was examined with the presence of chloride or bromide in a heat/PS process. Cl was found to have a dual effect (inhibition followed by enhancement) on the decomposition rates of organic pollutants, whereas the effects of Br are insignificant within the tested concentration (0-0.2 mM). However, some chlorinated or brominated compounds were still identified in this heat/PS system. Unexpectedly, the mineralization rates of AO7, phenol, benzoic acid and coumarin were not apparently inhibited. In addition, the formation of adsorbable organic halogen (AOX) in the heat/PS system was much less than those in the peroxymonosulfate (PMS)/Cl or PMS/Br systems. According to the results of kinetic modeling, SO was the dominating radical for AO7 degradation without Cl or Br, but Cl was the main oxidant in the presence of Cl, SO, Br and Br- were responsible for the oxidation of AO7 in the presence of Br. The present study assumes that X/HOX, rather than halogen radicals, is responsible for the enhanced formation of organohalogens. These findings are meaningful to evaluate the PS-based technologies for the high-salinity wastewater and to develop useful strategies for mitigating the negative effects of halides in advanced oxidation processes (AOPs).
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http://dx.doi.org/10.1016/j.envint.2019.104918DOI Listing
September 2019

Unveiling the activating mechanism of tea residue for boosting the biological decolorization performance of refractory dye.

Chemosphere 2019 Oct 28;233:110-119. Epub 2019 May 28.

Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China. Electronic address:

Conventional microbial treatments are challenged by new synthetic refractory dyes. In this work, tea residue was found serving as an effective activator to boost the decolorization performance of anthraquinone dye (reactive blue 19, RB19) by a new bacterial flora DDMY2. The unfermented West Lake Longjing tea residue showed the best enhancement performance. Seventeen main kinds of components in tea residue had been selected to take separate and orthogonal experiments on decolorization of RB19 by DDMY2. Results suggested epigallocatechin gallate (EGCG) in tea residue played important roles in boosting the treatment performance. Illumina MiSeq sequencing results confirmed that EGCG and tea residue pose similar impact on the change of DDMY2 community structure. Some functional bacterial genera unclassified_o_Pseudomonadales, Stenotrophomonas and Bordetella were enriched during the treatment of RB19 by EGCG and tea residue. These evidences suggested EGCG might be the key active component in tea residue that responsible for the enhancement effect on decolorization performance. These results revealed the activating mechanism of tea residue from the perspective of composition.
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http://dx.doi.org/10.1016/j.chemosphere.2019.05.205DOI Listing
October 2019

Chlorine incorporation into dye degradation by-product (coumarin) in UV/peroxymonosulfate process: A negative case of end-of-pipe treatment.

Chemosphere 2019 Aug 4;229:374-382. Epub 2019 May 4.

State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.

Recently, UV/peroxymonosulfate (PMS) seems as a panacea for the treatment of recalcitrant organic pollutants; however, the presence of high concentration of chloride in saline wastewater indeed complicates this end-of-pipe technology. Here a negative case of UV/PMS for the treatment of one of secondary degradation byproducts of dyes (coumarin, COU) is demonstrated. The removal rate of COU is reduced by addition of Cl (0-10 mM). Further increase in Cl content favors a rapid COU degradation, whereas Cl involvement seems to open a "Pandora's box": 1) a variety of chlorinated organic intermediates such as 4-chloroisocoumarin and 5-chloro-2-hydroxy-benzaldehyde are identified; 2) Accumulation and relative increase of absorbable organic halogen (AOX) with reaction time in the presence of high levels of chloride are observed; 3) the acute toxicity of the treated COU solution increases; 4) mineralization rate of COU decreases with the increasing [Cl]. The fluorescence intensity in the UV/PMS/COU system declines with the addition of Cl, implying the scavenging effects of chloride on hydroxyl radicals. The possible reaction pathways of COU are discussed. These findings highlight the imperativeness of minimizing auxiliary salt dosages in dyeing processes (i.e., source reduction) and developing new end-of-pipe technologies that can work in a saline environment.
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http://dx.doi.org/10.1016/j.chemosphere.2019.05.024DOI Listing
August 2019

Facile construction of flower-like bismuth oxybromide/bismuth oxide formate p-n heterojunctions with significantly enhanced photocatalytic performance under visible light.

J Colloid Interface Sci 2019 Jul 8;548:12-19. Epub 2019 Apr 8.

State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China.

Visible-light harvesting ability and charge separation efficiency are two pivotal factors for the design and construction of photocatalysts with an efficient ability for degrading toxic pollutants. Herein, visible-light-driven (VLD) BiOBr/BiOCOOH p-n heterojunction photocatalysts were prepared via an in-situ anion-exchange route. Through controlling the addition of KBr, we synthesized a series of BiOBr/BiOCOOH p-n heterojunctions with a different BiOBr loading. During the process, BiOBr production and homogeneous deposition on BiOCOOH with close interfacial interactions were realized by employing BiOCOOH microspheres as the self-sacrificing template. Compared to bare BiOBr and BiOCOOH, such p-n heterojunctions displayed dramatically strengthened performance in decomposing the industrial dye (rhodamine B, RhB) and antibiotic (tetracycline chloride, TC) under the irradiation of visible light. Among them, BiOBr/BiOCOOH p-n heterojunction with a BiOBr/BiOCOOH theoretical molar ratio of 0.6/0.4 (0.6Br-Bi) achieved the highest performance. Moreover, 0.6Br-Bi showed a good durability, indicating BiOBr/BiOCOOH p-n heterojunction possessed an excellently stable photocatalytic activity. Such an efficient and stable photocatalytic performance was mainly due to the formation of p-n heterojunctions which can profoundly improve the visible-light absorption and significantly depress the recombination of charge carriers. Trapping experiments and ESR tests verified that superoxide free radicals (O) and photogenerated hole (h) played a significant role in RhB degradation. This research affords a promising p-n heterojunction catalyst for wastewater treatment.
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http://dx.doi.org/10.1016/j.jcis.2019.04.024DOI Listing
July 2019

Fructose as an additional co-metabolite promotes refractory dye degradation: Performance and mechanism.

Bioresour Technol 2019 May 10;280:430-440. Epub 2019 Feb 10.

Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China; Institute of Biosciences, Freiberg University of Mining and Technology, Freiberg 09599, Germany; Biofilm Centre, University Duisburg-Essen, Essen, Germany.

In this work, the performance and mechanism for the boosting effects of fructose as an additional co-metabolite towards the biological treatment of reactive black 5 were systematically investigated. A decolorization efficiency of 98% was obtained in sample FRU200 (with 3 g/L fructose added based on 3 g/L yeast extract), which was 21% higher than that without fructose. Several intermediates with low molecular weight generated in sample FRU200 and different metabolic pathways were deduced. The bacterial community structure significantly changed due to fructose addition. Label-free quantitative proteomic approach suggested that several up-regulated proteins in sample FRU200 might play essential roles during the degradation. Furthermore, the mechanisms of RB5 degradation by proteins/enzymes of the dominant species in flora DDMZ1 were proposed. This work deepens our understanding of the molecular and ecological mechanism of fructose as co-metabolite enhancing the biodegradation of refractory organic pollutants by a natural bacterial flora.
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http://dx.doi.org/10.1016/j.biortech.2019.02.046DOI Listing
May 2019

Removal of active dyes by ultrafiltration membrane pre-deposited with a PSFM coagulant: Performance and mechanism.

Chemosphere 2019 May 11;223:204-210. Epub 2019 Feb 11.

School of Environmental Science and Engineering, University of South Australia, 2280, Australia.

A new, environmental friendly, polysilicate ferric manganese (PSFM) coagulant, composed of Fe, Mn and Si, was designed and developed. As part of the process, the PSFM flocs were then deposited onto an ultrafiltration (UF) membrane to increase the removal of active dyes and its antifouling properties in the presence of the active dye was tested. Influencing factors, such as dosage of coagulant and solution pH, were systematically investigated and included as the process optimization. The results show that PSFM flocs were well distributed on the membrane surface and a dense and homogeneous deposition layer was formed under optimal conditions. According to the characterization of PSFM floc by Fourier infrared (FTIR) and X-ray photoelectron spectroscopy (XPS), the major phase of PSFM floc is determined to be MnFeSiO(OH) and the functional groups of this component contribute positively to the coagulation performance. The removal rate of the active yellow dye reached 86% at pH 5.0 with small and regular floc formed in the dense deposition layers. At pH 11.0 loose deposition layers were formed by large flocs and the removal of the active yellow dye reduce to 11%. Therefore, PSFM has a commendable potential to be used for producing a kind of deposited UF membrane with an excellent performance by controlling the forms of flocs and the deposition layers, which is the key mechanism to achieve a high efficiency for removal of active yellow dye.
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http://dx.doi.org/10.1016/j.chemosphere.2019.02.034DOI Listing
May 2019

Effective Adsorption of Diesel Oil by Crab-Shell-Derived Biochar Nanomaterials.

Materials (Basel) 2019 Jan 11;12(2). Epub 2019 Jan 11.

College of Environmental and Science Technology, Donghua University, Shanghai 201620, China.

This study, for the first time, rendered crab shell activated biochar modified by potassium hydroxide (KOH) impregnation (CSAB), revealing a new potential application in the removal of diesel oil from oily wastewater. The structural characteristics of crab shell biochar (CSB) and CSAB were investigated by SEM, and the crystal structure and optical properties of as-prepared samples were analyzed using XRD and FTIR. Results showed that CSAB had stratified surface structure morphology, abundant functional groups, and that its high specific surface area could reach up to 2441 m²/g, which was about eight times larger than that of untreated CSB (307 m²/g). An adsorption isotherm study indicated that the actual adsorption process both of CSAB and CSB were found to fit better with the Freundlich equation. Moreover, chemical interaction controlled the adsorption kinetics efficiency while the adsorption equilibrium capacity was 93.9 mg/g. Due to its highly developed pore structure, unique surface characteristics, and effective adsorption performance, this low-cost activated carbon had the potential to serve as an efficient adsorbent for water pollution purification.
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http://dx.doi.org/10.3390/ma12020236DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6356441PMC
January 2019

Electroactive Modified Carbon Nanotube Filter for Simultaneous Detoxification and Sequestration of Sb(III).

Environ Sci Technol 2019 02 17;53(3):1527-1535. Epub 2019 Jan 17.

Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, College of Environmental Science and Engineering, Donghua University , 2999 North Renmin Road , Shanghai 201620 , P. R. China.

Herein, we rationally designed a dual-functional electroactive filter system for simultaneous detoxification and sequestration of Sb(III). Binder-free and nanoscale TiO-modified carbon nanotube (CNT) filters were fabricated. Upon application of an external electrical field, in situ transformation of Sb(III) to less toxic Sb(V) can be achieved, which is further sequestered by TiO. Sb(III) removal kinetics and capacity increase with applied voltage and flow rate. This can be explained by the synergistic effects of the filter's flow-through design, electrochemical reactivity, small pore size, and increased number of exposed sorption sites. STEM characterization confirms that Sb were mainly sequestered by TiO. XPS, AFS, and XAFS results verify that the Sb(III) conversion process was accelerated by the electrical field. The proposed electroactive filter technology works effectively across a wide pH range. The presence of sulfate, chloride, and carbonate ions negligibly inhibited Sb(III) removal. Exhausted TiO-CNT filters can be effectively regenerated using NaOH solution. At 2 V, 100 μg/L Sb(III)-spiked tap water generated ∼1600 bed volumes of effluent with >90% efficiency. Density functional theory calculations suggest that the adsorption energy of Sb(III) onto TiO increases (from -3.81 eV to -4.18 eV) and Sb(III) becomes more positively charged upon application of an electrical field.
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http://dx.doi.org/10.1021/acs.est.8b05936DOI Listing
February 2019

Synthesis of Flower-Like AgI/BiOCOOH p-n Heterojunctions With Enhanced Visible-Light Photocatalytic Performance for the Removal of Toxic Pollutants.

Front Chem 2018 26;6:518. Epub 2018 Oct 26.

State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai, China.

In this study, flower-like AgI/BiOCOOH heterojunctions were constructed through a two-step procedure involving the solvothermal synthesis of BiOCOOH microflowers followed by AgI modification using a precipitation method. These novel photocatalysts were systematically examined by XRD, UV-vis DRS, SEM, TEM, EDS, and PL spectroscopy techniques. The AgI/BiOCOOH heterojunction were studied as a decent photocatalyst for the removal of the industrial dye (rhodamine B, and methyl blue) and antibiotic (tetracycline) under visible light. The AgI/BiOCOOH heterojunctions are much more active than bare BiOCOOH, and AgI, which could be ascribed to the improved separation of charge carriers, resulting from the formation of p-n heterojunction between two constituents. The holes (h) and superoxide radical (•O ) were detected as the main active species responsible for the pollutant degradation. The results showed that a highly efficient visible-light-driven photocatalytic system was developed for the decomposition of toxic pollutants.
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http://dx.doi.org/10.3389/fchem.2018.00518DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6213583PMC
October 2018

Performance and microbial protein expression during anaerobic treatment of alkali-decrement wastewater using a strengthened circulation anaerobic reactor.

Bioresour Technol 2019 Feb 29;273:40-48. Epub 2018 Oct 29.

Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China; Institute of Biosciences, Freiberg University of Mining and Technology, Freiberg 09599, Germany.

Herein, a strengthened circulation anaerobic (SCA) reactor was employed for the treatment of actual alkali-decrement wastewater. The degradation mechanism of polyester oligomers and the relationship between the treatment performance and microbial community structure were systematically investigated using various advanced techniques. Results suggest that the accumulation of volatile fatty acids has an inhibitory effect on methanogenic activity. Molecular weight distributions suggest that only incomplete degradation of oligomers was achieved, due to acetogenic inhibition in the lower part of the SCA reactor. Meta-proteomic approach analysis revealed that the methanogens containing heterodisulfide reductase were the primary species involved in methane metabolism. Based on these findings, a possible degradation mechanism for alkali-decrement wastewater in the SCA reactor is proposed. This high-performance anaerobic reactor could be further scaled-up and optimized to serve as a promising and effective unit for the treatment of other refractory industrial wastewaters.
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http://dx.doi.org/10.1016/j.biortech.2018.10.055DOI Listing
February 2019

Iron Plaque: A Barrier Layer to the Uptake and Translocation of Copper Oxide Nanoparticles by Rice Plants.

Environ Sci Technol 2018 11 24;52(21):12244-12254. Epub 2018 Oct 24.

Key Laboratory of Water Pollution Control and Environmental Safety of Zhejiang Province , Zhejiang University , Hangzhou 310058 , China.

The waterlogging environment generally results in the deposition of iron plaque on plant roots, which may impact the fate of metal-based nanoparticles. Here, we investigated the influence of iron plaque on the uptake, translocation, and transformation of copper oxide nanoparticles (CuO NPs) in rice plants. The results show that the presence of iron plaque dramatically reduced the Cu contents in roots and shoots by 89% and 78% of those without iron plaque under 100 mg/L CuO NP treatment. Meanwhile, the Cu accumulation in plants was negatively related to the amount of iron plaque. X-ray absorption near edge structure (XANES) analysis demonstrated lower percentage of CuO but higher proportion of Cu(I) in shoots exposed to CuO NPs with the formation of iron plaque. Furthermore, micro X-ray fluorescence (μ-XRF) combined with μ-XANES revealed that the iron plaque in the root epidermis and exodermis consisted of goethite and ferrihydrite, which hindered the uptake of CuO NPs by roots. However, a few CuO NPs were still absorbed by roots via root hairs or lateral roots, and further translocated to shoots. But eventually, more than 90% of total Cu(II) was reduced to Cu(I)-cysteine and CuO in leaf veins of rice plants with iron plaque.
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http://dx.doi.org/10.1021/acs.est.8b02687DOI Listing
November 2018

Hierarchical heterostructures of BiMoO microflowers decorated with AgCO nanoparticles for efficient visible-light-driven photocatalytic removal of toxic pollutants.

Beilstein J Nanotechnol 2018 27;9:2297-2305. Epub 2018 Aug 27.

State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China.

Developing highly active and durable visible-light-driven photocatalysts for the degradation of toxic pollutants is of vital significance. Herein, AgCO nanoparticles were in situ formed on BiMoO microflowers to produce AgCO/BiMoO heterostructures via a facile procedure. The morphologies, phases, chemical compositions, and optical properties of AgCO/BiMoO were examined by multiple characterization techniques. The AgCO/BiMoO heterostructures exhibited substantially improved performance in the removal of industrial dyes (rhodamine B (RhB), methyl orange (MO), and methyl blue (MB)), and the antibiotic tetracycline hydrochloride (TC), compared with bare BiMoO and AgCO under visible-light irradiation. The enhancement of activity was attributed to the high charge-separation capacity, which results from the matched band alignment of the two components. The cycling experiments showed a good durability of AgCO/BiMoO. Holes were found to be the dominant active species accounting for the pollutant degradation. This compound is a promising candidate for wastewater treatment.
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http://dx.doi.org/10.3762/bjnano.9.214DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6122119PMC
August 2018

Deciphering the degradation/chlorination mechanisms of maleic acid in the Fe(II)/peroxymonosulfate process: An often overlooked effect of chloride.

Water Res 2018 11 28;145:453-463. Epub 2018 Aug 28.

State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.

In recent years, a significant effort has been devoted into investigating the effects of chloride on the degradation kinetics of aromatic pollutants. The impact of chloride on the decomposition of short-chain carboxylic acid intermediates from aromatics degradation has often been overlooked. In this study the roles of chloride in the oxidation of maleic acid (MA) in the Fe(II)/peroxymonosulfate (PMS) process was investigated. Degradation efficiency, reaction intermediates, adsorbable organic halogen (AOX) accumulation and mineralization were examined. The chloride ion (Cl) was found to have an overall negative impact on MA degradation and mineralization in the Fe(II)/PMS system. The presence of Cl led to the formation of chlorinated by-products and a high production of AOX. The mineralization of MA was decreased with increasing Cl concentrations. Kinetic modeling demonstrated the impact of various radicals largely depended on the concentration of Cl. The significance of Cl or Cl for MA destruction was enhanced with increasing Cl content, and overwhelmed that of SO when the Cl concentration was over 5 mM. In the absence of Cl, SO was the primary radical responsible for MA oxidation. A possible degradation pathway is proposed (cis-trans isomerization, decarboxylation and halogenations processes). These results may help to understand the full oxidation pathways of refractory aromatic compounds and the mechanism of chlorinated by-products formation in industrial saline wastewater treatment.
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http://dx.doi.org/10.1016/j.watres.2018.08.055DOI Listing
November 2018

Preparation of TiO/CN heterojunctions on carbon-fiber cloth as efficient filter-membrane-shaped photocatalyst for removing various pollutants from the flowing wastewater.

J Colloid Interface Sci 2018 Dec 10;532:798-807. Epub 2018 Aug 10.

State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China. Electronic address:

CN-decorated carbon-fiber (CF) cloth has been demonstrated as flexible filter-membrane-shaped photocatalyst for degrading the flowing wastewater, but its photocatalytic activity should be further improved. To enhance the separation efficiency of photogenerated carrier, herein we inserted TiO between CN and CF. With CF cloth as the substrate, the in-situ growth of TiO nanoparticles (diameter: 100-200 nm) was realized by a dip-coating/hydrothermal method; and CN nanosheets (thickness: 30-50 nm) were prepared on their surface by thermal polymerization. CF/TiO/CN cloth shows excellent visible photoabsorption (edge: ∼450 nm). Under visible light irradiation, CF/TiO/CN cloth exhibits improved photocurrent and photocatalytic activity for degrading various organic pollutants (methylene blue, acid orange 7, 4-chloprophenol, tetracycline hydrochloride (TC)) and reducing heavy-metal ions (Cr(VI)), compared with CF/CN and CF/TiO cloth. Especially, when CF/TiO/CN cloth is used as filter-membrane to photo-degrade the flowing wastewater (rate: 1.5 L h), the removal efficiency of TC and Cr(VI) reaches 87% and 88% after 7 grade, higher than that by CF/CN cloth (60% TC, 28% Cr(VI)) and CF/TiO cloth (8% TC, 7% Cr(VI)). Therefore, CF/TiO/CN cloth can be used as efficient filter-membrane-shaped photocatalyst for removing various organic pollutants and heavy metal in the flowing wastewater.
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http://dx.doi.org/10.1016/j.jcis.2018.08.028DOI Listing
December 2018

Comparative study of antiestrogenic activity of two dyes after Fenton oxidation and biological degradation.

Ecotoxicol Environ Saf 2018 Nov 22;164:416-424. Epub 2018 Aug 22.

College of Environmental Science and Engineering, Donghua University, Shanghai 201620, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China; State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Donghua University, Shanghai 201620, PR China. Electronic address:

In present study, two methods (Fenton oxidation and biological degradation) were used to degrade azo dye (Reactive Black 5, RB5) and anthraquinone dye (Remazol Brilliant Blue R, RBBR). The changes of antiestrogenic activities of these two dyes through two degradation methods were detected using the yeast two-hybrid assay method. Fluorescence spectroscopy together with gas chromatography-mass spectrometry (GC-MS) method was performed to analyze the metabolites of RB5 and RBBR after Fenton oxidation and biological degradation. Results indicated that by Fenton oxidation, the decolorization of RB5 and RBBR were 99.31% and 96.62%, respectively, which were much higher than that by biological degradation. Dissolved organic carbon (DOC) reduction rates of RB5 and RBBR after Fenton oxidation were also much higher than that after biological degradation. By Fenton oxidation, the antiestrogenic activities of RB5 and RBBR all decreased below detection limit after degradation, while by biological degradation all of them increased significantly after degradation. Fluorescence spectroscopy analysis and GC-MS analysis confirmed the degradation effects of RB5 and RBBR by these two degradation methods. In addition, fluorescence spectroscopy analysis revealed that the metabolites humic acid-like substances might contribute to the increasing of antiestrogenic activity of RB5 and RBBR after biological degradation.
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http://dx.doi.org/10.1016/j.ecoenv.2018.08.012DOI Listing
November 2018

AgVO Nanoparticles Decorated BiOCO Micro-Flowers: An Efficient Visible-Light-Driven Photocatalyst for the Removal of Toxic Contaminants.

Front Chem 2018 27;6:255. Epub 2018 Jun 27.

State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai, China.

Semiconductor-based photocatalysis is of great potential for tackling the environmental pollution. Herein, a novel hierarchical heterostructure of BiOCO micro-flowers decorated with AgVO nanoparticles was developed by a facile method. Various characterization techniques have been employed to study the physical and chemical property of the novel catalyst. The novel catalyst was utilized for the photocatalytic removal of industrial dyes (rhodamine B, methyl orange) and tetracycline antibiotic under visible-light irradiation. The results indicated that AgVO/BiOCO heterojunctions showed a remarkably enhanced activity, significantly higher than those of bare AgVO, BiOCO, and the physical mixture of AgVO and BiOCO samples. This could be ascribed to an enhanced visible-light harvesting capacity and effective separation of charge carriers by virtue of the construction of hierarchical AgVO/BiOCO heterojunction. Moreover, AgVO/BiOCO also possesses an excellent cycling stability. The outstanding performance of AgVO/BiOCO in removal of toxic pollutants indicates the potential of AgVO/BiOCO in real environmental remediation. Novel architectures of AgVO nanoparticles modified BiOCO micro-flowers were constructed.Novel AgVO/BiOCO exhibited excellent photocatalytic activity and stability.AgVO/BiOCO heterojunctions significantly promote the charge separation.
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http://dx.doi.org/10.3389/fchem.2018.00255DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6036280PMC
June 2018

Facile synthesis of cerium oxide nanoparticles decorated flower-like bismuth molybdate for enhanced photocatalytic activity toward organic pollutant degradation.

J Colloid Interface Sci 2018 Nov 28;530:171-178. Epub 2018 Jun 28.

State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China; International Center for Balanced Land Use (ICBLU), The University of Newcastle, Callaghan, NSW 2308, Australia. Electronic address:

One of the great challenges in the field of photocatalysis is to develop novel photocatalysts with excellent solar-light-harvesting capacity and separation efficiency of photo-induced charge. Herein, novel CeO/BiMoO heterojunctions were fabricated through in-situ precipitation of CeO nanoparticles (size: ∼26 nm) on the surface of flower-like BiMoO superstructures (diameter: 2.1-3.5 μm) by a simple method. The as-prepared photocatalysts were systematically characterized by a range of techniques. The photocatalytic degradation of rhodamine B (RhB) dye, methyl orange (MO) dye and tetracycline (TC) antibiotic by this novel photocatalyst was investigated under visible-light irradiation. The CeO/BiMoO heterojunction with a CeO/BiMoO weight ratio of 0.05 (0.05Ce-Bi) exhibited the highest photocatalytic activity with the RhB degradation efficiency of 100% in 75 min, which was considerably higher than those of pristine CeO (26.8%) and BiMoO (80.3%) as well as their physical mixtures (74.8%). The more efficient separation of electron-hole pairs was identified as the primary reason of the enhanced photocatalytic activity. Moreover, the synthesized material maintained satisfactory activity even after 6 recycling runs, indicating its high photocatalytic stability. Therefore, our finding offers a new avenue for development of stable and efficient heterojunction photocatalysts for environmental purification.
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http://dx.doi.org/10.1016/j.jcis.2018.06.084DOI Listing
November 2018

Treatment of industrial dyeing wastewater with a pilot-scale strengthened circulation anaerobic reactor.

Bioresour Technol 2018 Sep 18;264:154-162. Epub 2018 May 18.

Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China. Electronic address:

We developed a pilot-scale strengthened circulation anaerobic (SCA) reactor (with an effective volume of 27 m) and applied to the treatment of industrial textile wastewater. The treatment performance and the working mechanism were studied systematically and the key operational parameters were identified. The results demonstrated that a stable and excellent chemical oxygen demand removal efficiency of 62.7% and a maximum chromaticity removal efficiency of 73.5% were obtained at an optimal reflux ratio of 4. Interestingly, the bio-degradability was evidently improved after the SCA reactor treatment. The high throughput sequencing analysis indicated that the diversity of the bacteria or archaebacteria before the treatment was slightly higher than that after the treatment, which may be attributed to the production of certain toxic intermediates and/or characteristic pollutants during the treatment. Enzyme activity test and COD removal show that numerous microorganisms still maintained active in the anaerobic granular sludge even in a severe environment.
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http://dx.doi.org/10.1016/j.biortech.2018.05.063DOI Listing
September 2018