JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
·
2017
·
IF 2.625
Qin Chen,Huijie Hou,Danwei Zhang,Shaogang Hu,Tao Min,Bingchuan Liu,Changzhu Yang,Wenhong Pu,Jingping Hu,Jiakuan Yang
The ZnO/g-C 3 N 4 photocatalyst was prepared by ball milling and demonstrated enhanced photocatalytic degradation of RhB under visible light irradiation. The photocatalyst is consisted of ZnO and g-C 3 N 4 heterojunctions formed by the shear stress during the mechanical treatment. The addition of g-C 3 N 4 can improve the photocatalytic performance of ZnO under visible light. The heterojunction formed between ZnO and g-C 3 N 4 decreased the recombination rate of photogenerated carriers and improved the photocatalytic activity of the ZnO/g-C 3 N 4 hybrids. The optimal ZnO/g-C 3 N 4 photocatalyst with 10 wt% g-C 3 N 4 showed a degradation efficiency of 51.3% for RhB under visible light, which is 2.1 times higher than that of pristine ZnO. The electron paramagnetic resonance (EPR) measurement showed that the OH radicals are the dominant active species in photocatalytic process under both full solar spectrum and visible light irradiation. And the OH radical generation is much more efficient under full solar spectrum than that under visible light due to the UV response of ZnO. This work provides a simple method for the design and preparation of novel heterojunction photocatalysts.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Xin Huang,Man Su,Jizhi Zhou,Weikang Shu,Zhifeng Huang,Naiyun Gao,Guangren Qian
Persulfate based advanced oxidation processes have been well investigated, with the generation of radical species via various activation methods. This study reports an activation pathway of peroxydisulfate (S 2 O 8 2− , PDS) without radical production, achieved by the intercalation of PDS into Mg/Al-layered double hydroxide (LDH). Physical characterization indicated that the LDH was intercalated by PDS with the interlayer distance increasing to 0.917 nm. Approximately 93.9% of the phenol was decomposed by a LDH-PDS composite containing 0.4 mmol/g PDS, whilst no removal of phenol was achieved in the control group with PDS. Moreover, sulfate from decay of PDS was likely kept in the layers of LDH for no sulfate leakage in solution was observed. This is in accordance with the occurrence of characteristic peaks assigned for sulfate in FT-IR spectrum of LDH-PDS after reaction. Interestingly, radicals were not recorded by electron spin resonance measurement or radical scavenger tests during the oxidation process. The reactivity of PDS was likely improved by the basic sites on the LDH laminate, which provided OH to activate the O O bond in PDS. Further, the limited space of LDH layers reduce the bond cleavage of intercalated PDS and thus the generation of radicals. Therefore, the results proposed a non-radical reaction between phenol and PDS in the interlayer of LDH and developed a novel activation pathway for PDS in the elimination of organic contaminants.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Xiaoxue Pan,Liqing Yan,Chenguang Li,Ruijuan Qu,Zunyao Wang
The occurrence of benzophenone-3 (BP-3) in aquatic environments constitutes a potential risk to the environment and human health due to its phytotoxicity, carcinogenicity and endocrine disrupting effects. In this work, cobalt ferrite (CoFe 2 O 4 ) prepared by chemical co-precipitation method was used as a catalyst for the degradation of BP-3. The catalyst was characterized by SEM, TEM, XRD, XPS, BET and FT-IR spectroscopy, and its catalytic activity on BP-3 removal by persulfate (PS) was then evaluated at different operating parameters (catalyst loading, reaction temperature, solution pH and PS dose). The removal of BP-3 (1.31 μM) in 6 h reached 91% under the condition of [BP-3] 0 : [PS] 0 = 1: 1000, initial pH = 7.0, T = 25 °C and catalyst load = 500 mg L −1 . In addition to the satisfactory catalytic performance, the CoFe 2 O 4 also showed high stability and excellent recyclability. Electron paramagnetic resonance and radical quenching tests showed that sulfate radicals predominated in the decomposition of BP-3 by PS/CoFe 2 O 4 , while hydroxyl radicals also contributed to the catalytic oxidation process. Fifteen degradation products were identified by liquid chromatography-mass spectrometry (LC-MS), and two reaction pathways involving hydroxylation, demethylation, direct oxidation and benzene ring opening were proposed. This study could provide useful information for the potential application of CoFe 2 O 4 activated PS technology to treat water and wastewaters containing BP-3.
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2017
·
IF 9.446
Jianhua Yang,Zhengkui Li,Hongjie Zhu
A novel hydrogel catalyst (p(HEA/NMMA)-CuS) with the function of adsorption and degradation of organic pollutants in water was successfully synthesized using irradiation polymerization and in situ precipitation methods The composite hydrogel catalyst was characterized by SEM-EDS, TEM, swelling kinetics, zeta potential, TGA, XPS, FTIR and XRD. Besides, the effects and mechanisms of adsorption and degradation of sulfamethoxazole(SMX) as the representative pollutant by p(HEA/NMMA)-CuS hydrogel were observed. The results presented that adsorption process of SMX on complex hydrogel fit well to Langmuir monolayer adsorption, and followed a pseudo-second-order rate equation. The decomposition of SMX by p(HEA/NMMA)-CuS hydrogel in aqueous solution under 500 w visible light achieved balance in 24 h, the removal ratio reached 95.91%, and the SMX was mineralized with 43.56%. Hydroxyl radicals was detected as the reactive species using EPR in the system, degradation intermediates of SMX were further analyzed by LC-TOF-MSMS, a possible pathway for SMX degradation was presented. The degradation mechanism of SMX was also illustrated by theoretical calculations of frontier electron densities. Furthermore, mineralization, stability and regeneration results indicated that the developed hydrogel catalyst, p(HEA/NMMA)-CuS hydrogel, was promising in practical application.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Shanshan Liu,Xu Zhao,Huabin Zeng,Yanbin Wang,Meng Qiao,Wei Guan
In this work, persulfate (S 2 O 8 2− , PS) was introduced to the photoelectrocatalytic (PEC) system, which consisted of a γ-Bi 2 MoO 6 photoanode and a copper foil cathode (Bi 2 MoO 6 /Cu/PEC/PS system). Significant enhancement of diclofenac sodium (DCF) degradation efficiency was observed in this system under visible light irradiation. At an applied bias of 1.5 V and initial solution pH of 5.62, the removal efficiency of DCF with an initial concentration of 10 mg/L was increased from 19.4% in the PEC process to 86.3% in the PEC process with 10 mM PS addition. The pseudo-first-order kinetic rate constant of DCF degradation was increased from 0.1112 h −1 to 1.0498 h −1 . Active free radicals involving SO 4 − and HO were produced in this process, which were confirmed by electron spin resonance analysis. Furthermore, the surface variation of copper foil cathode was characterized by FE-SEM, GI-XRD, XPS and in situ Raman spectroscopy. It was demonstrated that Cu 2 O formed on the surface in the reaction process with the S 2 O 8 2− addition, which was further confirmed by the photoelectrochemical analysis of the cathode. The surface Cu(0)–Cu(I)–Cu(II)–Cu(0) redox cycle of cathode was proposed, which was responsible for the persulfate activation, leading to the generation of free radicals. This work may provide a new perspective on the combined utilization of different technologies for catalytic contaminant removal.
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2017
·
IF 4.208
Xiaohua Ren,Huanhuan Guo,Jinkui Feng,Pengchao Si,Lin Zhang,Lijie Ci
3D porous N-doped reduced graphene oxide (N-rGO) aerogels were synthesized by a hydrothermal reduction of graphene oxide (GO) with urea and following freeze-drying process. N-rGO aerogels have a high BET surface of 499.70 m 2 /g and a high N doping content (5.93–7.46 at%) including three kinds of N (graphitic, pyridinic and pyrrolic). Their high catalytic performance for phenol oxidation in aqueous solution was investigated by catalytic activation of persulfate (PS). We have demonstrated that N-rGO aerogels are promising metal-free catalysts for phenol removal. Kinetics studies indicate that phenol degradation follows first-order reaction kinetics with the reaction rate constant of 0.16799 min −1 for N-rGO-A(1:30). Interestingly, the comparison of direct catalytic oxidation with adsorption-catalytic oxidation experiments indicates that adsorption plays an important role in the catalytic oxidation of phenol by decreasing the phenol degradation time. Spin density and adsorption modeling demonstrates that graphitic N in N-rGO plays the most important role for the catalytic performance by inducing high positive charge densities to adjacent carbon atoms and facilitating phenol adsorption on these carbon sites. Furthermore, the activation mechanism of persulfate (PS) on N-rGO was first investigated by DFT method and PS can be activated to generate strongly oxidative radical (SO 4 · - ) by transferring electrons to N-rGO.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2017
·
IF 6.065
Suding Yan,Jinyao Geng,Rui Guo,Yue Du,Hui Zhang
Electro-assisted Fenton-like (EAFL) system based on sulfate radicals (SO 4 − ) has been extensively explored for the degradation of recalcitrant organic contaminant. Nevertheless, external power supply should be provided uninterruptedly in the EAFL process and thus the high energy consumption is ineluctable. Recently, microbial fuel cell (MFC), a bio-electrochemical system where exoelectricigens are used to catalyze fuels into electricity energy has gained popularity mainly due to its renewability. Herein, a novel heterogeneous EAFL system, hydronium jarosite (HJ) activation of peroxymonosulfate (PMS) in an electrochemical reactor driven by an uncoated single-chamber MFC (MFC/HJ/PMS), was employed to decolorize acid orange 7 (AO7). The results suggest that the MFC/HJ/PMS system can remove AO7 efficiently in a wide pH range (3–9). The concentration of total iron leached could meet European Union discharge standards and hydronium jarosite could be used at least three circles. The results of electron paramagnetic resonance analysis and radical scavenging experiments indicate SO 4 − is the major active species responsible for the AO7 elimination. The work provides an efficient, energy-saving and cost-effective approach to treat organic wastewater and develops the conceivable utilization of hydronium jarosite, precipitates produced in hydrometallurgical process.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Muhammad Danish,Xiaogang Gu,Shuguang Lu,Ayyaz Ahmad,Muhammad Naqvi,Usman Farooq,Xiang Zhang,Xiaori Fu,Zhouwei Miao,Yunfei Xue
Zeolite supported nano zero valent iron copper bimetallic composite (Z-nZVFe-Cu) was synthesized using an ion exchange method. The morphology and physico-chemical properties of the Z-nZVFe-Cu composite were determined using transmission electron microscopy (TEM), scanning electron microscopy (SEM), Brunauer Emmett Teller (BET), energy dispersive X-ray spectra (EDS), Fourier transform infrared spectroscopy (FTIR) and X-ray diffractometer (XRD). The results showed that iron and copper nano particles were well dispersed on the zeolite sheet. The degradation efficiency of trichloroethylene (TCE) achieved was more than 95% using Z-nZVFe-Cu as a heterogeneous Fenton like catalyst. An efficient removal of total organic carbon (TOC) was promoted as compared to zeolite supported iron nano composite (Z-nZVFe) and unsupported nano iron (nZVFe). Electron spin resonance (ESR) detection confirmed the intensity of hydroxyl radicals (OH ) in the system. While benzoic acid (BA), a probe indicator for the quantification of OH , demonstrated the higher intensity of hydroxyl radicals in Z-nZVFe-Cu as compared to Z-nZVFe and nZVFe. The less iron and copper leaching of from Z-nZVFe-Cu presented its higher stability and better catalytic activity, displaying its potential long term applications for TCE degradation in groundwater.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Dahu Ding,Chao Liu,Yuefei Ji,Qian Yang,Lulu Chen,Canlan Jiang,Tianming Cai
Uniform magnetite nanoparticles (MNP) were prepared through a facile hydrothermal routine and subjected to the heterogeneous activation of persulfate (PS) to degrade norfloxacin (NOR). The degradation efficiency reached 90% within 60 min (the concentration of NOR and PS was 15 μM and 1 mM, respectively; dose of MNP: 0.3 g L −1 ; pH: 4.0). However, it was greatly inhibited with the increase of pH, especially at basic condition (pH 0 = 9.0). This was probably due to the precipitation of the ferrous ions leached from the surface of MNP. In addition, hydroxyl radical was found to dominate the degradation process at acidic condition while both sulfate and hydroxyl radicals contributed to the degradation at neutral condition. Except the leached form, the structural ferrous ion on the surface of MNP also participated in the activation process through the redox reactions, as illustrated by the X-ray photoelectron spectroscopy (XPS) analysis. Finally, four degradation pathways were tentatively proposed based on the identified intermediates and the transformation of piperazinyl ring seemed to be the primary one.
✓ 已验证
产品关联
DOI
高影响因子
WATER AIR AND SOIL POLLUTION
·
2016
·Vol. 227
·期 10
·1-8
·
IF 1.551
Li Ying,Yang Lijiao,Chen Cheng,Lan Yeqing
In this paper, Zn(0)-catalyzed ozonation degradation of acid orange 7 (AO7) and its impact factors including solution pH, Zn loading, and AO7 initial concentration were investigated through a series of bath experiments. The results demonstrated that Zn could markedly accelerate the degradation of AO7 by ozone (O 3 ) and the degradation efficiency of AO7 increased by 77 and 71 % within 30 min as compared with those in the systems of O 3 alone and Zn/air, respectively. The reuse of Zn resulted in a slight decline in AO7 degradation, suggesting that a coating of ZnO on the surface of Zn particles weakened Zn catalytic activity. The optimal removal of AO7 was achieved in a wide pH range of 4 to 10, and a lower or higher pH was not conducive to the degradation of AO7. In addition, the degradation efficiency of AO7 increased with Zn loading but decreased with AO7 initial concentration. The introduction of free radical scavengers into the system of AO7/Zn/O 3 confirmed that O 2
•− , rather than •OH, was the main free radicals responsible for the rapid removal of AO7. The degradation of AO7 by O 3 assisted with Zn could be well expressed with pseudo-first-order kinetic model.
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2016
·
IF 8.328
Yaowen Gao,Simiao Li,Yixi Li,Linyu Yao,Hui Zhang
Photocatalysis based on metal-organic frameworks (MOFs) is being actively investigated as a potential technology in visible light harvesting and utilizing processes. Herein we report that MIL-53(Fe), an earth-abundant Fe-containing MOF material, shows photocatalytic activity for the degradation of Acid Orange 7 (AO7) from aqueous solution under visible LED light irradiation, yet the photocatalytic performance of bare MIL-53(Fe) was not satisfactory due to the fast recombination of photoinduced electron-hole pairs. This can be effectively overcome by adding the external electron acceptor (e.g., persulfate, PS) to the catalytic process. The accelerated photocatalytic degradation of AO7 is demonstrated by the result that the degradation efficiency of AO7 in the MIL-53(Fe)/PS/Vis process reached almost 100% within 90 min as compared to only 24% under the identical experimental conditions for the MIL-53(Fe)/Vis process. To investigate the mechanism of the MIL-53(Fe)/PS/Vis process, photoluminescence (PL) spectra, electrochemical measurements and electron paramagnetic resonance (EPR) analysis were performed. It was concluded that the efficient separation of photogenerated electrons and holes by the introduced PS and the subsequent formation of reactive radicals resulting from the activation of PS by photogenerated electrons accounted for the accelerated photocatalytic degradation of AO7 in the MIL-53(Fe)/PS/Vis process. Furthermore, the applicability of MIL-53(Fe) used in the persulfate-mediated photocatalytic process was systematically investigated in terms of the identification of reactive radicals, the reusability and stability of the photocatalyst, as well as the effect of operating parameters. The findings of this work highlighted the great potential of MOFs as photocatalysts and elucidated a new opportunity for persulfate remediation of contaminated water.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Xiaoling Zhang,Mingbao Feng,Liansheng Wang,Ruijuan Qu,Zunyao Wang
Recently, the toxicity of sunscreen has received extensive attention due to their potential endocrine disrupting effect. In the present study, nitrogen and sulfur co-doped multi-walled carbon nanotubes loaded CuFe 2 O 4 (NS-CNTs/CuFe 2 O 4 ) catalyst was rationally designed and synthesized by co-precipitation method for the degradation of 2-phenylbenzimidazole-5-sulfonic acid (PBSA, a typical sunscreen addition). The catalyst was fully characterized by scanning electron microscope, transmission electron microscope, X-ray diffraction, Fourier transform infrared spectroscopy, nitrogen gas uptake, and X-ray photoelectron spectroscopy. Then the kinetics, pathways and mechanisms of catalytic degradation of PBSA were studied in NS-CNTs/CuFe 2 O 4 activated peroxymonosulfate (PMS) solution. The catalyst showed high catalytic activity, stability and reusability in PBSA removal. The results of electron paramagnetic resonance (EPR) and quenching experiments suggested that sulfate radicals (SO 4 − ) predominated in the activation of PMS by NS-CNTs/CuFe 2 O 4 . The synergistic effect between CuFe 2 O 4 and NS-CNTs was proposed in PMS activation. In addition, eight degradation intermediates of PBSA were identified by liquid chromatography mass spectrometry (LC–MS), and degradation pathways were further proposed. Overall, this study provides insights of PBSA removal by NS-CNTs/CuFe 2 O 4 activated PMS at ambient temperature.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）