CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Xiaoyu Yang,Xuanxuan Lei,Shaokun Tang
A simple hydrothermal method is utilized to fabricate hierarchically olive-like γ -Al 2 O 3 using ionic liquid [Bmim]BF 4 as the structure directing agent . The olive-like γ -Al 2 O 3 presents uniform morphology with the average diameter of 500 nm and rich mesopores. As template, ionic liquid [Bmim]BF 4 plays a crucial role in the controllable morphology of the product. [Bmim]BF 4 is absorbed on the AlOOH nanoparticles surface via the H-bond interaction and induces crystalline oriented growth. Then the forming AlOOH nanosheets self-assemble into olive-like hierarchical structure through π–π stack interaction. Given that the structure advantage of the olive-like γ-Al 2 O 3 and the limited study concerning cerium-based catalysts in Fenton-like reaction, nano-CeO 2 / γ -Al 2 O 3 supported catalyst is prepared and used in Fenton-like degradation for the first time. The result suggests that the olive-like γ -Al 2 O 3 support not only reduces the surface energy with more uniform CeO 2 (ca. 4–5 nm) dispersion but also improve the concentration of Ce 3+ active sites. The CeO 2 / γ -Al 2 O 3 catalyst displays superior catalytic activity for the degradation of Orange II (AO7) compared with pure CeO 2 nanoparticles.
研究领域:
材料科学
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环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Fang Zhu,Jianfeng Ma,Qiuyue Ji,Hao Cheng,Sridhar Komarneni
A special catalytic system was obtained by using ZnMn 2 O 4 (ZMO) materials to activate Na 2 S 2 O 8 and catalytically degrade organic dye orange II under visible light irradiation. The ZMO nanoparticles were prepared by a simple one-step method and characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS). In this study, the ZMO/Na 2 S 2 O 8 system was used to degrade orange II, and the degradation rate reached 97.44% in 60 min. ZMO catalysts could be recycled for at least five times, and its degradation rate was only decreased by 1.84%. The free radicals produced during the degradation of orange II were studied by classical quenching experiments, and the different types of free radicals produced in the system were further confirmed by electron paramagnetic resonance (EPR) spectroscopy. The catalytic degradation of orange II in this system was mainly caused by the production of superoxide , sulfate and hydroxyl radicals, which achieved high degradation.
研究领域:
环境科学
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催化化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Qingzhuo Ni,Jianfeng Ma,Changhai Fan,Yong Kong,Mingguo Peng,Sridhar Komarneni
A spinel-type Co-Mn oxide was designed and synthesized through a two-step oxidation-precipitation method at modest temperatures. The Co-Mn oxide was applied as the catalyst in the presence of NaHSO 3 under visible light irradiation in order to establish the superiority of heterogeneous photo-chemical catalysis system. In the above system, the Co-Mn catalyst exhibited much better catalytic capability than that in either single photocatalysis or chemocatalysis system, implying that the Co-Mn catalyst could well combine photocatalysis and chemocatalysis to obtain the highest degradation efficiency of up to 94% within 40 min when using Orange II as the target pollutant. Recycling experiments results showed that the as-obtained catalyst has excellent stability and recyclability. Powder X-ray diffraction (XRD) analysis showed that the as-obtained Co-Mn catalyst had a cubic MnCo 2 O 4.5 spinel structure. Because of relatively low temperature (180 ℃) synthesis, the catalyst was formed with nanoparticles (25–65 nm) and high specific surface area as confirmed by SEM and BET analyses. XPS indicated the presence of both manganese and cobalt species that serve as reactive sites for the catalytic oxidation reactions. Rational degradation mechanisms responsible for superior catalytic activity and durability were proposed based on a series of experimental results. The active species such as Mn(III), holes and sulfate and hydroxyl radicals were proposed to be responsible for the outstanding degradation results.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2015
·Vol. 6
·期 7
·2296-2304
·
IF 5.426
Kaixin Zhu,Junhu Wang,Yanjie Wang,Changzi Jin,Ayyakannu Sundaram Ganeshraja
Refractory and non-biodegradable pollutants produced by industries have inevitably brought great threat to human life. Integrating several kinds of advanced oxidation processes (AOPs) into one system has been proposed to be an efficient strategy to remove such pollutants from the environment at low cost. In this study, magnetic zinc ferrite fine nanoparticles, firstly synthesized by a novel soft chemical solution process, showed super reactivity, good reusability and easy separation ability for visible-light-induced Orange II degradation in an integrated ZnFe2O4/PMS (peroxymonosulfate, 2KHSO5·KHSO4·K2SO4, OXONE) aqueous system. Powder X-ray diffraction, transmission electron microscopy, and 57Fe Mössbauer and X-ray photoelectron spectroscopy were employed to characterize the structure and morphology as well as recognize the physicochemical changes of the fine nanoparticles before and after the reaction. The generated oxidizing intermediates during the degradation process were detected by electron paramagnetic resonance spectroscopy and classic quenching experiments, which confirmed that both sulfate radical (SO4˙−) and hydroxyl radical (˙OH) co-existed in the degradation process. The systematic condition experiments further verified the dual functionality of the ZnFe2O4/PMS system, which actively acted as a photocatalyst and a PMS activator for dye molecule oxidation under visible light irradiation. This study proves that photocatalysis and PMS activation for remediation of organic pollutants in water can be easily integrated into one system by using zinc ferrite nanoparticles as an environmentally friendly catalyst.
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
MATERIALS CHEMISTRY AND PHYSICS
·
2022
·
IF 4.778
Lingli Ji,Qixing Xiao,Lijun Zhu,Sridhar Komarneni,Jianfeng Ma
Carbon dots (CDs)-modified Cr 2 O 3 (CDs@Cr 2 O 3 ) composites were synthesized by solvothermal process followed by calcination to improve their catalytic performance. The physical and chemical properties of the composites were determined by XRD , SEM , TEM, BET and XPS . With the aid of sodium persulfate, the activity of CDs@Cr 2 O 3 to oxidize Orange II by non-radicals was studied under various conditions. The experimental results determined the optimal dosage of PDS to be 0.1 g and the degradation results showed that after 45 min, the degradation rate of Orange II reached to 98.4% with the CDs@Cr 2 O 3 /PDS/Vis system. The adsorption capacity of CDs@Cr 2 O 3 for Orange II was closely related to pH, and this phenomenon is further explained by the isoelectric point. A series of experiments proved that non-free radicals played a crucial role in the oxidation process , in which singlet oxygen ( 1 O 2 ), superoxide radical (O 2 •− ) and photo-generated holes (h + ) were determined as the important reactive oxygen species (ROS). In addition, the present study found that increasing dissolved oxygen could promote the reaction and the catalyst maintained good degradation performance after five cycles suggesting its stability.
研究领域:
环境科学
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2017
·
IF 4.217
Lixuan Duan,Xuejun Zhou,Siting Liu,Penghui Shi,Weifeng Yao
We report a 3D-hierarchically Co 3 O 4 /graphene hydrogel (CGH) composite as a catalyst activator of peroxymonosulfate (PMS) for sulfate radical-based degradation of Orange II in a heterogeneous system. The physicochemical performance of the composite is analyzed by X-ray diffraction spectra, scanning electron microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The results demonstrate that the samples are prepared resoundingly. The CGH hybrid composite completely removes Orange II wastewater within 6 min; furthermore, after five runs, the catalyst activity remains essentially unchanged and the macrostructure is followed consistently. This unusual macrostructure hydrogel of supported cobalt oxide indicates a high feasibility of commercial promotion to remove the azo dye.
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
WATER AIR AND SOIL POLLUTION
·
2023
·Vol. 234
·期 11
·1-12
·
IF 2.9
Wang Xilin,Sun Xiaojing,Dai Ping,Xu Dongyan
This study focuses on preparation of a novel Fe 3 O 4 @C/RM composite by carbothermal reduction of red mud (RM) with scrap tire-derived carbon black and its application for the degradation of orange II in water by activating PMS. X-ray diffraction (XRD) measurements revealed that hematite (Fe 2 O 3 ) was reduced to Fe 3 O 4 in the pyrolysis process above 600 o C. The reduction pathway of Fe 2 O 3 was inferred by detecting the gas emissions during carbothermal reduction. Morphology analysis indicates that Fe 3 O 4 nanoparticles were encapsulated in a carbon matrix, forming a composite with the residual components of RM. The as-prepared Fe 3 O 4 @C/RM composite exhibited high performance toward orange II degradation with 95.9% removal of orange II within 90 min. Electron paramagnetic resonance (EPR) and quenching tests were applied to illustrate the activation processes of peroxymonosulfate. Both radical and non-radical oxygen species are responsible for the efficient degradation of orange II in the Fe 3 O 4 @C/RM/PMS system.
研究领域:
环境科学
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材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2020
·
IF 5.774
Shuo Feng,Bing Xiao,Meng Wu,Yun Wang,Rufen Chen,Hui Liu
In this study, copper phosphide (Cu 3 P) was used as a heterogeneous catalyst for peroxydisulfate (PDS) activation and Orange II degradation. This catalyst functions over a broad pH range, from 3.0 to 9.0 and the degradation rate of Orange II is 95.2% at 15 min under optimal conditions. The rapid degradation kinetics can be described by the Behnajady-Modirshahla-Ghanbery (BMG) equation. Sulfate radical, the main reactive oxidizing species, along with OH and O 2 − , were responsible for pollutant degradation. The Cu 3 P catalyst exhibited good stability and excellent anti-interference performance toward Cl − , NO 3 − , and HCO 3 − anions. The removal efficiency of Orange II remained close to 100%, even after five rounds of recycling reactions. The rapid catalytic mechanism of Cu 3 P is attributed to the dual-catalysis center in Cu 3 P (Cu and P) and simultaneous existence of three cycles ( Cu II → Cu III → Cu II , Cu I → Cu II → Cu I , and Cu δ+ → Cu 1+δ+ → Cu δ+ ) on the surface and interior of Cu 3 P. This study sheds new light on the fabrication of high-performance heterogeneous catalysts to solve the environmental problems.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2021
·
IF 4.539
Yu Lei,Yixing Hao,Hao Cheng,Jianfeng Ma,Yong Qin,Yong Kong,Sridhar Komarneni
Fe 2 O 3 @CeO 2 nanocomposites were synthesized by water bath heating method to activate NaHSO 3 for Orange II dye (50 mg L −1 ) degradation, which reached up to 98.2% within 120 min. The Fe 2 O 3 @CeO 2 and NaHSO 3 dosages and the molar ratios of Ce and Fe in Fe 2 O 3 @CeO 2 were investigated to obtain the optimum conditions as follows: 0.02 g Fe 2 O@CeO 2 , 0.1 g NaHSO 3 and the molar ratio of Ce and Fe was 5:2 (designated as Ce-Fe-1, or simply Fe 2 O 3 @CeO 2 ). In addition, Fe 2 O 3 @CeO 2 catalyst displayed superior catalytic performance to those materials that were previously reported, as verified by the good stability (reached 90.9% after three cycles) and high degradation rate of Orange II (98.2%) of the currently developed material. Existence of · SO 4 – and · OH radicals were verified by Electron Spin Resonance Spectroscopy during degradation, and these radicals are proposed to have high degradation efficiency of Orange II. On the basis of the detected radicals, a possible degradation mechanism was proposed to provide more choices for the application of sulfite in advanced oxidation processes (AOPs).
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2021
·Vol. 11
·期 11
·3715-3723
·
IF 6.119
Daoqing Liu,Qianwei Li,Jinbao Hou,Huazhang Zhao
The coexistence of aliovalent cations may facilitate the formation of electronic and ionic defects, altering the catalytic properties of manganese oxide. In this paper, a series of mixed-valent manganese oxides (MnOx) were prepared by a hydrothermal route and tested for heterogeneous activation of peroxydisulfate for Orange II degradation in aqueous solution. The morphology, crystal structure and surface chemistry of the MnOx were adjusted by the addition of ethanol in the hydrothermal process. The physicochemical properties were characterized and evidence from X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) indicated that MnOx exhibited a mixed crystal phase structure of Mn2O3, Mn3O4 and MnO2. The catalytic properties of the three samples prepared with 5%, 10%, and 20% volume fractions of ethanol (denoted as MnOx-5, MnOx-10, and MnOx-20) were found to be related to the valent states of Mn, and MnOx-10 exhibited a better performance with a mole ratio of Mn4+/ Mn2+ close to 1.0. The electrochemical characterization demonstrated that MnOx-10 performed a more effective redox process which may determine the catalytic activity of MnOx. Moreover, quenching tests, electron paramagnetic resonance (EPR) and gas chromatography-mass spectrometry (GC-MS) were used to evaluate the possible activation processes of peroxydisulfate (PDS) and the intermediates of Orange II degradation. This catalyst preparation strategy provides a new idea for the preparation of high-efficiency environmental catalysts.
研究领域:
环境科学
·
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2021
·
IF 4.094
Xiaorui Zhang,Yu Mei,Hao Cheng,Jianfeng Ma,Fang Zhu,Sridhar Komarneni
NiO and CeO 2 composite metal oxides (NiO–CeO 2 ) were synthesized by sol-gel method to investigate a degradation system by persulfate (PS) activation with the assistance of visible light (Vis). The phase composition of NiO–CeO 2 was detected by X-ray diffraction (XRD), the morphology of NiO–CeO 2 was characterized by scanning electron microscope (SEM), and the result of X-ray photoelectron spectroscopy (XPS) proved the element composition and valence state of the NiO–CeO 2 . In the Vis/PS/NiO–CeO 2 system, the degradation rate of Orange II using a concentration of 50 mg/L was as high as 90% in 15 min but it increased to as high as 99% in 60 min. Mechanism studies have shown that the combination of NiO and CeO 2 generated more oxygen vacancies , and activated persulfate to generate active oxygen species. Moreover, the effects of visible light , persulfate concentration and pH were evaluated, and the results showed that the participation of visible light and persulfate could significantly increase the degradation efficiency of Orange II, but pH had little effect on the degradation. Quenching experiments and detection by ESR showed that O 2 ‾, •SO 4 ‾, •OH, and 1 O 2 all contribute to the removal of Orange II. In addition, the recovery and reuse properties of NiO–CeO 2 may lead to sustainable treatment of wastewater.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2017
·
IF 4.217
Chaoqun Tan,Yujie Dong,Lei Shi,Qin Chen,Shengwei Yang,Xiaoyu Liu,Jinfeng Ling,Xuefeng He,Dafang Fu
The degradation of Orange II (Org II) by ferrous activated peroxymonosulfate (PMS) was inspected. The maximum degradation efficiency of 62.3% in 90 min occurred at 0.286 mM [PMS] 0 , corresponding to 1:1 molar ratio of Fe 2+ : PMS. Results show that poor recovery of Fe 2+ accounts for poor degradation in the slow stage. The species of reactive radicals were determined through indirect way by quenching agents, as well as directly by in situ EPR spin trapping tests. Results indicated that hydroxyl radicals instead of sulfate radicals were responsible for Org II degradation. The removal of Org II degradation would increase to 93.3% in 90 min as reaction temperature increased to 60 °C. The activation energy for PMS and Fe 2+ /PMS alone was calculated to be 77.2 kJ/mol and 34.7 kJ/mol, respectively. The removal efficiency of total organic carbon (TOC) was 11.0% and 43.8% when [Fe 2+ ] 0 :[PMS] 0 :[Org II] 0 was 5:5:1 and 34:34:1, respectively. The main degradation products of Org II in system were supposed to be heterocyclic compounds containing a five-atom ring. Results demonstrated that Fe 2+ /PMS technology is promising technology for water pollution.
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
危险品化学品经营许可证（带存储）