Materials
·
2023
·Vol. 16
·期 7
·2650
·
IF 3.4
Yaohui Xu,Liangjuan Gao,Jinyuan Yang,Qingxiu Yang,Wanxin Peng,Zhao Ding
A porous CeO2was synthesized following the addition of guanidine carbonate to a Ce3+aqueous solution, the subsequent addition of hydrogen peroxide and a final hydrothermal treatment. The optimal experimental parameters for the synthesis of porous CeO2, including the amounts of guanidine carbonate and hydrogen peroxide and the hydrothermal conditions, were determined by taking the adsorption efficiency of acid orange 7 (AO7) dye as the evaluation. A template−free hydrothermal strategy could avoid the use of soft or hard templates and the subsequent tedious procedures of eliminating templates, which aligned with the goals of energy conservation and emission reduction. Moreover, both the guanidine carbonate and hydrogen peroxide used in this work were accessible and eco−friendly raw materials. The porous CeO2possessed rapid adsorption capacities for AO7 dye. When the initial concentration of AO7 was less than 130 mg/L, removal efficiencies greater than 90.0% were obtained, achieving a maximum value of 97.5% at [AO7] = 100 mg/L and [CeO2] = 2.0 g/L in the first 10 min of contact. Moreover, the adsorption–desorption equilibrium between the porous CeO2adsorbent and the AO7 molecule was basically established within the first 30 min. The saturated adsorption amount of AO7 dye was 90.3 mg/g based on a Langmuir linear fitting of the experimental data. Moreover, the porous CeO2could be recycled using a NaOH aqueous solution, and the adsorption efficiency of AO7 dye still remained above 92.5% after five cycles. This study provided an alternative porous adsorbent for the purification of dye wastewater, and a template−free hydrothermal strategy was developed to enable the design of CeO2−based catalysts or catalyst carriers.Keywords:porous CeO2;template−free;adsorption;adsorption efficiency;acid orange 7
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Separations
·
2024
·Vol. 11
·期 9
·274
·
IF 2.5
Wenjun Xu,Qianyi Wang,Jintao He,Fuzhen Liu,Xiang Yan,Yin Xu
The development of appropriate and effective periodate (PI) activation technology is currently a popular research area. This study presents a novel efficient photocatalytic activation approach of PI for pollutant degradation based on carbon nitride (g-C3N4) and visible light (Vis). The results show that the system can remove 92.3% of acid orange 7 (AO7) within 60 min under the g-C3N4/PI/Vis reaction system. The degradation rate constant (kobs) reached 4.08 × 10−2min−1, which is 4.21,5.16 times, and 51.3 times higher than that of the g-C3N4/Vis system (9.7 × 10−3min−1), PI/Vis system (7.9 × 10−3min−1) and the g-C3N4/PI system (7.96 × 10−4min−1), respectively. Clearly, the addition of PI significantly enhances the degradation efficiency of AO7 in the system. Additionally, under the same reaction conditions, the presence of PI showed excellent oxidation capacity in the photoactivation process compared with other common oxidants, such as peroxymonosulfate, peroxydisulfate, and H2O2. Moreover, the g-C3N4/PI/Vis system showed excellent removal of AO7 across a wide range of pH levels and in the presence of various anions. Electron paramagnetic resonance (EPR) and quenching experiments suggested that the superoxide anions (•O2−) and singlet oxygen (1O2) dominated in the oxidation of pollutants in the g-C3N4/PI/Vis system. In addition, the catalyst showed relative stability during cyclic testing, although a slight reduction in degradation efficiency was observed. In brief, the g-C3N4/PI/Vis system is highly efficient and environmentally friendly, with significant application potential in wastewater treatment.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 121
·99935-99943
·
IF 3.84
Huanxuan Li,Jinquan Wan,Yongwen Ma,Yan Wang,Zeyu Guan
The impacts of common anions and organic matter, initial pH and PS dosage on the oxidation of acid orange 7 (AO7) by persulfate (PS) activated with zero-valent iron (ZVI) were investigated. The present findings revealed that maximum AO7 decolorization occurred at pH 3.0, and increasing the system pH resulted in a greater decrease in AO7 decolorization rates. AO7 decolorization efficiency was 100% at 120 min when the molar ratio of PS : AO7 was 5 : 1. Interestingly, ClO4−, CH3COO− and humic acid (HA) were found to accelerate AO7 decolorization rates while other anions retarded AO7 decolorization in the following sequence: NO2− > H2PO4− > HPO42− > EDTA > SO42− > CO32− > HCO3− > NO3− > Cl−. ClO4−, CH3COO− and HA with 50 mM, 10 mM and 1.0 mg L−1, respectively were found to be the optimal concentrations for AO7 decolorization. The removal efficiencies of AO7 were decreased by 90.3%, 51.5%, 58.7% and 38.2%, respectively over 120 min in addition of NO2− (50 mM), H2PO4− (50 mM), HPO42− (50 mM) and EDTA (50 mM). The other anions including SO42−, CO32−, HCO3−, NO3− and Cl− led to a decrease change of less than 20%. The mechanisms for the influence were complexation reactions with Fe2+ generated from ZVI, consuming of sulfate radicals (SO4−˙) by scavenging reactions, and oxidation reactions involving inorganic ions. The reason for the acceleration by CH3COO− and HA was probably through acting as an electron ‘shuttle’ and facilitating electron transfer from the ZVI surface to PS and resulted in more Fe2+ and SO4−˙. However, the acceleration caused by ClO4− was presumably ascribed to the oxidizing of ZVI directly by ClO4− to produce more Fe2+.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
·
2024
·
IF 4.1
Yingzi Lin,Mengshi Wang,Junjie Chen,Siwen Li,Yuanyuan Zhang,Liangliang Wei,Ningning Sun,Chengyu Liu,Junjie Zhao
Based on the deficiency of the Fe 2+ catalyzed persulfate (PDS) process, ultraviolet (UV) synergistic Fe 2+ activated PDS system was introduced in this study for the degradation of acid orange 7 (AO7) dye. The effects of different initial pH, PDS dosage, Fe 2+ dosage, and different UV intensities on the degradation rate of AO7 were investigated, and a kinetic model for the apparent reaction rate was determined. The results showed that the UV/Fe 2+ /PDS system was effective in degrading AO7 in a wide pH range. Under optimal conditions, 96 % removal of AO7 was achieved in 10 min. The effects of different inorganic anions on AO7 were discussed; Cl − had little effect on the degradation effect, and SO 4 2− , NO 3 − and HCO 3 − inhibited the degradation of AO7 by the system to varying degrees. The presence of reactive radicals (SO 4 ·− and·OH) in the reaction was determined by quenching experiments and EPR capture and their degradation contribution was further investigated. Nine intermediates of AO7 were detected by LC-MS/MS, and the degradation pathway of AO7 was inferred by combining with UV-Vis spectra. Finally, the ecotoxicity and tritogenic effects of AO7 intermediates were assessed by Toxtree and T.E.S.T toxicity prediction models, which showed that the final degradation product toxicity was non-mutagenic, non-teratogenic, and devoid of hereditary and non-hereditary carcinogenicity.
研究领域:
环境科学
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化学工程
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毒理学
✓ 已验证
产品关联
DOI
高影响因子
Symmetry-Basel
·
2025
·Vol. 17
·期 2
·224
·
IF 2.2
Yaohui Xu,Yong Li,Liangjuan Gao,Zhao Ding
CeO2has a potential application in the purification of organic dye wastewater because of the abundant oxygen vacancy (VO) defects in its crystals. In this study, a cubic CeO2microsphere with layered interleaved symmetrical 3D flower-like morphology was synthesized, and its adsorption capacity for acid orange 7 (AO7) was further enhanced by Y doping. The impact of varying amounts of Y ions on the phase composition, lattice parameters, and morphology of the product was investigated, revealing that 4 mol.% was determined as the doping level limit of Y ions in CeO2crystals. XPS, Raman, and H2−TPR techniques were employed to compare surface species changes before and after 4 mol.% Y doping in the CeO2crystals, including O−Ce(III), O−Ce(IV), O−Y(III), and VOcorrelation, yielding a rough quantitative assessment of these species. The 4 mol.% Y-doped CeO2(2.0 g/L) demonstrated the highest removal rate for 20 mg/L of AO7 dye within just 20 min to reach adsorption–desorption equilibrium, half the time required by undoped CeO2, achieving an impressive adsorption rate of 94.6%, compared to only 69.5% for undoped CeO2at 20 min. The adsorption capacity of undoped CeO2was enhanced by 19.05% through the doping of 4 mol.% Y, achieving a value of 16.56 mg/L. The feasibility of enhancing the adsorption capacity of CeO2by Y doping provides a reference for the application of CeO2and other metal oxides.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2019
·
IF 5.108
Xin Liu,Baoling Yuan,Jing Zou,Lingbin Wu,Lin Dai,Hongfang Ma,Kai Li,Jun Ma
The activation of persulfate by Fe(II) coupled with hydroxylamine (the HA/Fe(II)/PS system) was highly effective for the degradation of refractory organic contaminants under acidic pH conditions. However, owing to the precipitation of ferric hydroxide and/or the slow reduction from Fe(III) to Fe(II), the HA/Fe(II)/PS system was invalid under neutral and alkaline pH conditions. In this study, it was observed that the degradation of acid orange 7 (AO7) was strongly enhanced over the wide pH range of 2–9 when trace Cu(II) (0.5–5 μM) was spiked into the HA/Fe(II)/PS system. It was evident that Cu(I) was generated via the reduction of Cu(II) by HA in the bimetallic system at both pH 3 and pH 8, and the steady concentration of Fe(II) in the bimetallic system was much higher than that in the HA/Fe(II)/PS system due to the rapid reaction between Fe(III) and Cu(I). Quenching experiments using tert-butyl alcohol, methanol and sodium bromide as the scavengers and electron spin resonance experiments confirmed that the primary reactive species responsible for AO7 degradation were sulfate radical at both pH 3 and pH 8, rather than hydroxyl radical and Cu(III). Nevertheless, sulfate radical was mainly produced by Fe(II)-activated PS at pH 3, while both Cu(I) and Fe(II) made important contributions to the generation of sulfate radical at pH 8. The bimetallic system was also highly effective in degrading other organic contaminants, such as phenol, diclofenac, reactive red 2 and orange G. This study might provide a promising idea based on Fe(II)-activated PS for degrading organic contaminants over a wide pH range.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2013
·
IF 3.473
Huanxuan Li,Jinquan Wan,Yongwen Ma,Yan Wang,Mingzhi Huang
The environmental impact caused by azo dyes such as acid orange 7 (AO7) is currently a major concern, mainly due to their toxicity, potential carcinogenic nature and difficult degradation. This research described the heterogeneous reactions of persulfate with milli-ZVI (1 mm), micro-ZVI (150 μm) and nano-ZVI (50 nm) under various experimental conditions. The results demonstrated that the combination of persulfate with ZVI was efficient in promoting the degradation of AO7 with the pseudo first-order and second-order kinetics reaction, and different ZVI types exhibited respective level of ability to activate persulfate to degrade acid orange 7, which was ranged as nano-ZVI > micro-ZVI > milli-ZVI. However, the presence of dissolved SiO 2 decreased the AO7 degradation ratio and prolonged the persulfate half-life. The iron corrosion products coating on the ZVI after reaction was comprised of α-Fe 2 O 3 , Fe 3 O 4 and α-FeOOH with some Fe 8 O 8 (OH) 6 SO 4 , which was identified by Raman spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared (FTIR). With the presence of SiO 2 , surface complexes of ≡FeH 3 SiO 4 or ≡ Fe H 2 SiO 4 - for binding of silicates were formed. These observations indicated that the dissolved SiO 2 in the ZVI activated persulfate system affected the corrosion of iron, altered the surface area with the adsorption of SiO 2 , and appeared to influence the decomposition of persulfate and AO7.
研究领域:
环境科学
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化学工程
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2022
·Vol. 29
·期 31
·47549-47560
·
IF 5.19
You Wenqiao,Li Youlin,He Dandan,Zeng Youmei,Zhu Jiangwei,You Xiaofeng,Wang Kang,Zhou Guangming,Peng Guilong
In the present study, pyrophosphate (PP) was used to activate peroxymonosulfate (PMS) for acid orange 7 (AO7) removal under neutral pH conditions. The removal rate of AO7 (20 mg/L) was 84% within the reaction time with a rate constant value of 0.0165 min −1 under optimum conditions. Additionally, the effects of the concentrations of PMS and PP in solutions with various pH values and the coexisting inorganic anions on AO7 removal were measured. In addition, the performance of phosphate (P(V)) on PMS activation was compared with that of phosphite (P(III)) species. In contrast to P(III), the concentration of P(V) showed a positive correlation with the efficiency of AO7 decolorization. PMS activation in different types of buffer solutions was also examined, and the results indicated that the decolorization efficiency of AO7 induced by PP addition, and the buffer solution also contributed to PMS self-decomposition. Singlet oxygen ( 1 O 2 ) might be the primary reactive oxygen species (ROS) in the PP/PMS system in which AO7 is decolorized at an initial pH of 7.06, as indicated by quenching experiments and electron spin resonance (ESR) tests. Therefore, PP/PMS systems may be promising technologies for removing organic contaminants, particularly for PP-rich electroplating wastewater.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF PHOTOENERGY
·
2022
·
IF 2.535
Yaohui Xu,Chi Deng,Changxue Dong,Qin Wang,Nunan Gao
Acid Orange 7 (AO7) is one of the most common azo dyes; however, its strong azo bond makes them difficult to biologically degrade. We sought to degrade AO7 dye using CeO2 as a promising alternative photocatalyst. CeO2 powders were synthesized with alternative monoethanolamine (MEA), diethanolamine (DEA), and triethanolamine (TEA) as a precipitant by solvothermal process combined calcination in air. Compared to the oxygen storage capability of Blank-CeO2 (0.186 mmol O2/g), that of MEA-CeO2 synthesized in the presence of MEA as a precipitant increased by 21.0%, while that of DEA-CeO2 and TEA-CeO2 synthesized in the presence of DEA and TEA as precipitants were decreased. Importantly, such MEA-CeO2 exhibited the highest photocatalytic activity than Blank-, DEA-, and TEA-CeO2 in degradation of AO7 under simulated sunlight illumination, and the removal rate of AO7 by MEA-CeO2 could reach 98.3% within 100 min.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
WATER AIR AND SOIL POLLUTION
·
2024
·Vol. 235
·期 8
·1-12
·
IF 3.8
Li Qi,Zhu Yanping,Liu Yanbiao,Chen Xiaoguang,Jiang Nan,Yan Mengying,Li Xuhua,Xing Haoyu,Bao Yinzhou,Huang Manhong
Antimonate (Sb(V)), sulfate and acid orange 7 (AO7) are common pollutants in printing and dyeing wastewater. Currently, there have been no reports about the effects of sulfate and AO7 on Sb(V) removal by anaerobic granular sludge (AnGS). In this study, the Sb(V) removal and Sb(Ш) accumulation was revealed in presence of sulfate and AO7, and the role of adding granular activated carbon (GAC) was investigated. Results showed that sulfate inhibited Sb(V) removal by AnGS (S + Sb, k = 0.101). GAC alleviated the inhibition of sulfate on Sb(V) removal and Sb(V) removal rate increased by 1.9 times (GAC + S + Sb, k = 0.187). Meanwhile, GAC promoted sulfate reduction by AnGS. AO7 inhibited sulfate reduction, thereby alleviating the inhibition of sulfate on Sb(V) removal, and Sb(V) removal rate increased by 1.5 times (S + Sb + dye, k = 0.147). When Sb(V), sulfate and AO7 coexisted, adding GAC actually inhibited Sb(V) removal (GAC + S + Sb + dye, k = 0.067), which may be due to GAC promoted the reduction of sulfate and AO7 by AnGS. The microbial community analysis revealed that Acinetobacter genus was related to Sb(V) reduction, with higher relative abundance in GAC + S + Sb (49.4%) and S + Sb + dye groups (28.9%). These results provided guidance for anaerobic treatment of printing and dyeing wastewater. Graphical Abstract
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 74
·70271-70276
·
IF 3.289
Ying Huang,Zhaohui Wang,Changling Fang,Wenqian Liu,Xiaoyi Lou,Jianshe Liu
Addition order of reagents in the Acid Orange 7 (AO7) degradation process was investigated by varying the concentration of Fe(II), the Fe(II)/peroxymonosulfate (PMS) molar ratio and stepwise addition of Fe(II) and PMS. The importance of addition order of reagents was confirmed and an order of Fe(II)–PMS to improve the oxidation efficiency was recommended.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 102
·84303-84310
·
IF 3.84
Lian Duan,Yanling Chen,Kaixuan Zhang,Huoyan Luo,Jianxin Huang,Aihua Xu
The cobalt-based heterogeneous catalysts CoxOy-N/GAC were prepared by pyrolysis of a cobalt–phenanthroline complex on granular active carbon (GAC) in a nitrogen atmosphere, and tested for the degradation of Acid Orange 7 using hydrogen peroxide as a benign oxidant in a bicarbonate aqueous solution. Characterization by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and electron spin resonance spectroscopy revealed the formation of a cobalt oxide nanoparticle shell with a metallic Co core on the surface of GAC; and the nitrogen substituted the selected carbon atoms during the pyrolysis process and bonded to cobalt. The catalysts were active for dye decolorization in an aqueous solution containing 10 mM H2O2 and 5 mM NaHCO3 at room temperature. They also presented good stability with nearly no loss of cobalt ions after the reaction, in comparison with the high leaching of Co (0.25 mg L−1) from the CoxOy/GAC catalyst without nitrogen. The production of intermediates, the formation of reactive radicals and the effect of HCO3− were also investigated to further explore the efficiency of the catalyst. This study can provide a promising way for the activation of the green oxidant H2O2 in a bicarbonate aqueous solution by heterogeneous cobalt catalysts for environmental remediation.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）