International Journal of Environmental Research and Public Health
·
2016
·Vol. 13
·期 6
·602
·
IF 2.035
Penghua Yin,Zhihao Hu,Xin Song,Jianguo Liu,Na Lin
Perfluorooctanoic acid (PFOA) is an emerging contaminant of concern due to its toxicity for human health and ecosystems. However, successful degradation of PFOA in aqueous solutions with a cost-effective method remains a challenge, especially for groundwater. In this study, the degradation of PFOA using activated persulfate under mild conditions was investigated. The impact of different factors on persulfate activity, including pH, temperature (25 °C–50 °C), persulfate dosage and reaction time, was evaluated under different experimental conditions. Contrary to the traditional alkaline-activated persulfate oxidation, it was found that PFOA can be effectively degraded using activated persulfate under acidic conditions, with the degradation kinetics following the pseudo-first-order decay model. Higher temperature, higher persulfate dosage and increased reaction time generally result in higher PFOA degradation efficiency. Experimental results show that a PFOA degradation efficiency of 89.9% can be achieved by activated persulfate at pH of 2.0, with the reaction temperature of 50 °C, molar ratio of PFOA to persulfate as 1:100, and a reaction time of 100 h. The corresponding defluorination ratio under these conditions was 23.9%, indicating that not all PFOA decomposed via fluorine removal. The electron paramagnetic resonance spectrometer analysis results indicate that both SO4−• and •OH contribute to the decomposition of PFOA. It is proposed that PFOA degradation occurs via a decarboxylation reaction triggered by SO4−•, followed by a HF elimination process aided by •OH, which produces one-CF2-unit-shortened perfluoroalkyl carboxylic acids (PFCAs, Cn−1F2n−1COOH). The decarboxylation and HF elimination processes would repeat and eventually lead to the complete mineralization all PFCAs.Keywords:PFOA;activated persulfate;free radicals;defluorination
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Bo Feng,Kaining Sun,Guangbo Che,Tianyi Yang,Yongya Zhang,Qianqian He,Tianrui Chang,Lijing Wang,Renquan Guan
To address the need for efficient catalysts that excel in persulfate (PDS) activation and carrier extraction, a gadolinium oxide (Gd 2 O 3 ) modified strontium titanate (SrTiO 3 ) photocatalyst has been devised for the photo-Fenton reaction, targeting the degradation of tetracycline and ciprofloxacin. This innovative photocatalyst harnesses the formation of a heterojunction between Gd 2 O 3 and SrTiO 3 , which dramatically enhances PDS activation and boosts carrier extraction efficiency by 6.8 times. Notably, it achieves approximately 90% degradation of tetracycline across various pH levels and approximately 80% degradation of ciprofloxacin under acidic and neutral conditions. Importantly, the photocatalytic treatment significantly mitigates the biotoxicity of the degraded antibiotics, emphasizing its environmental safety and efficacy. The underlying mechanisms of PDS activation and carrier transport have been rigorously verified through theoretical calculations, while the potential photocatalytic pathways and mechanisms of antibiotic degradation have been elucidated using Fukui function analysis and liquid chromatography-mass spectrometry (LC-MS). This comprehensive approach underscores the photocatalyst’s potential for advanced environmental remediation applications.
研究领域:
环境科学
·
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
·
2024
·
IF 8.1
Chun-Yang Li,Tong Zhai,Wentao Gu,Huan Lv,Xue-Meng Ji,Man-Man Wang,Jing-Min Liu,Shuo Wang
Advanced glycosylation end products (AGEs) are becoming a prominent issue in the biomedical and food safety industries because of their strong relationship to human health. Here, a MIL@PANI@LDH photocatalyst was prepared by in-situ growth method, realizing thorough elimination of AGEs for the first time. The synthesized photocatalysts used MIL-101 holding remarkably specific surface area as the core and PANI with a large number of amino and imine groups as the linker to ensure excellent adsorption capacity. The lamellar LDH structure grown in the outermost layer, on the other hand, introduces a narrower band gap and stronger light absorption ability, capable of activating sodium persulfate (PS) and generating free radicals with powerfully oxidizing ability. They work in concert to achieve the effective degradation. Through the optimization of the reaction conditions, the best photochemical performance could be achieved with a Zn/Al molar ratio of 3:1, and the degradation rates of AGEs were greater than 99.8 % (within 150 min). Additionally, multiple radical synergistic and non-radical action pathways involved in the system were revealed. The precision-engineered catalysts also exhibited high stability, reusability, and desirable biosafety, offering an effective and sustainable solution to the problem of purifying hazardous substances in real application.
研究领域:
环境科学
·
材料科学
·
生物医学
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2021
·
IF 4.837
Xianlin Zeng,Lu Wang,Yongqing Zhang,Shaoqi Zhou,Zebin Yu,Xun Liu,Chuan Chen
This work delivered a simple modification method for promoting persulfate (PS) activation by zero-valent iron (ZVI). The results showed that the ball-milled FeS/Fe 0 had the highest imidacloprid (IMI) removal efficiency among the tested materials (FeS, Fe 0 , mixed FeS/Fe 0 , and ball-milled FeS/Fe 0 ) under the same conditions (activator dosage = 0.1 g/L; PS = 2.5 mM; IMI = 0.15 mM). Ball milling ZVI and FeS together makes the mixture smaller in particle size, higher in crystallinity and produces iron-sulfur compounds that covered the surface. These changes contributed to the rapid corrosion of ZVI and thereby promoted the persulfate activation. Increasing the ball milling rotational speed made these enhancements more obvious. In addition, the Fe 3+ reduction by FeS created an acidic condition and further promoted the Fe 0 release. The optimal parameters for ball milling FeS and Fe 0 were a FeS/Fe 0 (1:1–4:1, w:w) and a 600 rpm of rotational speed for 30 min. The impacts of different ball-milled material dosages, persulfate dosages, anion concentrations and initial pH were investigated. In the optimum ball-milled FeS/Fe 0 /PS system (ball-milled FeS/Fe 0 = 0.1 g/L; PS = 2.5 mM), the pollutant (IMI = 0.15 mM) removal efficiency reached 95% at 10 min. The common dissolved anions (3 mM SO 4 2− /NO 3 − /Cl − ) and alkaline conditions only had a slight inhibitory effect. The IMI removal efficiency still reached 95% at 15 min. These observations suggest that the Fe 0 -based persulfate activation technique was enhanced by ball milling with FeS, making it more feasible for remediation of organic pollutant removal.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Jiaxuan Yang,Wenqian Li,Jialong Chen,Nuo Cheng,Tianyi Wang,Hesong Wang,Daliang Xu,Han Zhang,Jinlong Wang,Langming Bai,Heng Liang
Wastewater increases and water shortage crises have forced the rapid innovation of water reuse technologies. Ceramic membrane process (CM), as one of the key technologies for wastewater reclamation, can effectively light the current difficulties. However, membrane fouling and low retention rate are critical bottles that hinder its further application. Herein, we proposed yolk-shell Co 3 O 4 spheres modified CM (CoHM-CM) activating peroxymonosulfate (PMS) to improve membrane filtration performance. The results showed that the synergistic effect of size exclusion of CM and spatial confinement of CoHM enhanced the collision between organic pollutants and active sites. CoHM-CM/PMS (30 mg CoHM loading combined with 0.5 mM PMS dosage) degraded 100 % of 10 mg/L phenol, bisphenol F and sulfamethoxazole, and 91.29 % of 5 mg/L carbamazepine at an instant of membrane filtration. This process efficiently removed secondary effluent organic matter and reduced membrane fouling resistance by more than 70 % in actual wastewater environments. Besides, the yolk-shell catalytic membrane had strong Co 2+ regeneration capacity and chemical stability. It coupled PMS-generated sulfate radicals and singlet oxygen play a core role in increasing the membrane interface energy barrier and releasing the developing tendency of membrane pore blocking to severe cake layer filtration fouling. The results provided a new opportunity for wastewater remediation based on the yolk-shell modified membrane technology.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Environmental Research and Public Health
·
2022
·Vol. 19
·期 24
·16651
·
IF 4.614
Nan Yang,Zhihan Zhang,Shicheng Zhang,Liting Chen,Jia Zhu,Jingsi Gao
In order to improve the catalytic activity and recycling performance of semiconductor activators, and improve the activation pathway of persulfate, graphitic carbon nitride (g-C3N4) was prepared by calcining melamine, and a composite activator Ag2O/g-C3N4based on g-C3N4supported metal oxide was prepared using a precipitation method. The morphology, structure, and basic properties of the composites were characterized using SEM, XRD, FT-IR and XPS. The activation efficiency of the Ag2O/g-C3N4composite activator on peroxodisulfate (PDS) was explored. The results showed that Ag2O in the composite activator was highly dispersed on the surface of g-C3N4and did not change the molecular structure of g-C3N4significantly. Under different activation systems, the degradation process of MO was best fitted under the pseudo-second-order reaction kinetic model, compared to the separate g-C3N4or Ag2O activated PDS systems; the activation of the PDS system with Ag2O/g-C3N4had the best effect on MO degradation; and the composite activator Ag2O/g-C3N4showed better activation performance. Under the conditions that the mass combined ratio of Ag2O in the activator was 12%, the initial concentration of PDS was 4 mmol/L, the initial concentration of the activator was 1.25 g/L, and the initial pH was 3, the degradation degree of MO reached 99.4% after 40 min reaction. The free radical quenching experiment proved that the active substances that could degrade MO in the system were SO4−· and ·OH, and the effect of SO4−· was greater than that of ·OH. The degradation degree of MO in the reaction system remained above 80% after four cycles of use, and the crystal structure of Ag2O/g-C3N4did not change significantly before and after the reaction. The above results show that Ag2O/g-C3N4is an efficient and stable composite activator with good application potential in the treatment of dye wastewater by activating PDS.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Yangbo Huang,Yun Yang,Zeyu Guan,Qiang Li,Dongsheng Xia
In this study, a new functionalized flat-sheet ceramic membrane (CuCo 2 O 4 -CM) was prepared by an impregnation-calcination strategy and used in the removal of Bisphenol A (BPA). Various characterization results indicated that a CuCo 2 O 4 layer was uniformly anchored on the membrane surface and the internal porous channels. The CuCo 2 O 4 -CM possessed a smaller mean pore size (80 nm) and better hydrophilicity than the pristine α-Al 2 O 3 substrate after modification. The catalytic degradation in CuCo 2 O 4 -CM /PMS system revealed that 92.1% of BPA and 70.0% of TOC could be removed under optimal conditions (pH = 7.0, C BPA = 30 mg/L and C PMS = 2 mM). Meanwhile, the membrane showed good reusability and improved antifouling properties. During the reaction, four reactive oxygen species (·OH, SO 4 ·- , O 2 ·- and 1 O 2 ) were generated and they all responded for the degradation of BPA. In addition, the mechanism of PMS activation and BPA degradation were proposed. This study presented an efficient oxidation process for BPA degradation and outlines the synergistic effect of separation and catalytic oxidation.
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
Environmental Science-Nano
·
2020
·Vol. 7
·期 7
·1899-1911
·
IF 7.683
Chunyang Nie,Zhenhua Dai,Wenjie Liu,Xiaoguang Duan,Chengyin Wang,Bo Lai,Zhimin Ao,Shaobin Wang,Taicheng An
Carbon-catalyzed persulfate activation is a metal-free advanced oxidation process for abating aqueous organic micropollutants. Recently, the electron-transfer mechanism in the activation of peroxydisulfate (PDS) has attracted tremendous interest due to its unknown nonradical reaction pathways. The conventionally used atomic-scale descriptors of adsorption energy (Eads), O–O bond length (lO–O) and S–O bond length (lS–O) cannot accurately reflect the ability of the functionalities of PDS in its activation. In this work, a new descriptor, local electrophilicity index (ω), which represents the oxidative capacity of adsorbed S2O82−, was included to identify the intrinsic active sites in carbocatalysts via density functional theory calculations. To verify the reliability of the proposed criteria, the catalytic performances of a series of highly boronated and nitrogenated carbon nanotube/nanosheet composites (BCN-NT/NS) with tailored physicochemical properties were comparatively studied for activating PDS to degrade phenol. By integrating the computational and experimental results, the catalytic activity of BCN-NT/NS was determined to not only be related to the contents of heteroatom dopants (B and N), but also the positions of B and N in the co-doping configurations. This study offers reliable criteria for determining the intrinsic catalytic sites in carbocatalysts for the activation of PDS based on an electron-transfer mechanism, which assists the rational design of nanocarbons as advanced catalysts for metal-free oxidation and water remediation.
研究领域:
环境化学
·
催化
·
材料科学
·
水处理
✓ 已验证
产品关联
DOI
高影响因子
ENERGY
·
2024
·
IF 9
Chunquan Li,Xinlin Wang,Kefu Ma,Jiayu Liu,Fang Yuan,Qizhou Wang,Zhiming Sun
Coal slime-based peroxymonosulfate (PMS) catalytic materials were synthesized utilizing coal slime (CS) as raw material under the N 2 atmosphere in this study. Raw and calcined coal slime were systematically characterized concerning morphologies, pore structures , chemical bonds, phase constituents, and defect density . Results show that after being calcinated with FeCl 2 ∙4H 2 O at 750 °C, the specific surface area increased by nearly 21.0 times higher than that of CS. The addition of FeCl 2 ∙4H 2 O has certain effect on the chemical bonds of calcined coal slime, i.e. the Fe elements can be fixed by the silicon aluminum skeleton with sekaninaite (Fe 2 Al 4 Si 5 O 18 ) and aluminum iron silicon (Al 0.5 Fe 3 Si 0.5 , above 650 °C) generation, and the I D /I G values increase to 2.96 for CS-FeCl 2 -750. In addition, the degradation percentage of phenol by using CS-FeCl 2 can achieve 100% in 25 min under optimized conditions. Furthermore, 1 O 2 plays a major role in phenol degradation, followed by • OH and SO 4 •− in the CS-FeCl 2 /PMS system from the quenching experiments and electron paramagnetic resonance results. Overall, the novel CS-FeCl 2 material displays good application prospects in the field of effluent treatment , with efficient utilization of carbonaceous and silicon aluminum skeleton in coal slime.
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
CHEMOSPHERE
·
2019
·
IF 5.108
Liying Wu,Qian Zhang,Junming Hong,Zhengyu Dong,Ji Wang
This research describes the function of oxygen vacancy on CoFe 2 O 4-x for persulfate (PS) activation. Novel CoFe 2 O 4-x with different vacancy degrees that were successfully developed via hydrogen calcination were characterized using X-ray diffraction analyzer (XRD), Fourier transform infrared (FTIR) spectra, Raman spectroscopy , scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), H 2 temperature-programmed reduction (H 2 -TPR), cyclic voltammetry (CV), electrochemical impedance spectra (EIS), nitrogen adsorption-desorption isotherms and dynamic light scattering. The activation of catalysts was analyzed using Bisphenol A (BPA) as pollutant, and the main active species generated during the reaction were identified by using N 2 bubbling and scavenger experiments. Possible oxidation degradation pathways of BPA were speculated using gas chromatography–mass spectrophotometry (GC-MS) and total organic carbon (TOC) analysis. Findings indicated that the oxygen vacancies promoted electronic transfer and participated in the redox cycle from Co 3+ /Fe 3+ to Co 2+ /Fe 2+ to generate 1 O 2 and O 2 - . O 2 - , OH and SO 4 - generated from oxygen vacancy; moreover, PS activation could further degrade BPA to small molecules, such as benzenes and quinones . Finally, the toxicity of the reaction mixtures was evaluated and found that the acute toxicity to Daphnia magna decreased after 120 min treatment.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Lu-Lu Zhou,Peng-Xi Liu,Ying Ding,Jia-Rui Xi,Li-Juan Liu,Wei-Kang Wang,Juan Xu
Heterogeneous catalysts with hierarchically porous structure are highly efficient to catalyze chemical reactions. In this work, two-dimensional (2D) nano-flakes assembled flower-like NiO is fabricated and utilized for activating peroxydisulfate (PDS) to degrade organic pollutants bisphenol A (BPA). The results demonstrate that the prepared catalyst exhibits well organized flower structure composed of uniform 2D nano-flakes. PDS combines with the catalyst to form surface-activated NiO-PDS complex, subsequently depriving electrons from BPA. For the optimized NiO-12 catalyst, large specific surface area and hierarchically porous structure benefit to exposes abundant active sites while low resistance promotes electrons transfer, bringing the high BPA degradation rate constant of 0.28 min −1 under the condition of 20 mg/L initial concentration. NiO-12 exerts a capability of catalyzing PDS to mineralize 34% of practical packaging wastewater. This study provides a new strategy to fabricate hierarchical 2D porous catalysts for persulfate activation, with application potential in practical wastewater treatment.
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
CELLULOSE
·
2020
·Vol. 27
·期 6
·3287-3300
·
IF 4.21
Zhang Su-Feng,Li Hao,Hou Chen,Liu Li-Na,Wang Yang,Zhao Meng-Ke,Liang Chen
Abstract The treatment of dyes in wastewater is important to solve environmental problems. Advanced oxidation processes has been proved to be an effective treatment. In this work, a novel nanocomposite catalyst of ZIF-9@Fe 3 O 4 (cobalt-containing zeolitic imidazolate framework-9 coated Fe 3 O 4 nanocomposite) modified reduced graphite oxide (RGO) was prepared for the first time and coded as ZIF-9@CA-Fe 3 O 4 /RGO. Then, ZIF-9@CA-Fe 3 O 4 /RGO was immobilized on a cellulose membrane to obtain a composite membrane, which was used as a composite catalyst for activating peroxymonosulfate to degrade methylene blue (MB). The results demonstrated that the composite membrane could efficiently degrade approximately 96% of MB in 9 min without adjusting the initial pH and maintain good catalytic activity even after seven cycles. Furthermore, the composite membrane can be easily separated from the solution at the end of the reaction. This work indicates that the composite membrane has a broad application prospect in industrial applications. Graphic abstract
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
危险品化学品经营许可证（带存储）