RSC Advances
·
2018
·Vol. 8
·期 49
·27796-27804
·
IF 2.936
Xiangdan Zhang,Zongchao Liu,Qingqing Kong,Guoguang Liu,Wenying Lv,Fuhua Li,Xiaoxuan Lin
Clofibric acid is one of the most frequently detected pharmaceuticals in various aquatic environments. Photodegradation of clofibric acid in water under simulated sunlight was investigated. The effects of different initial concentrations, pH conditions and dissolved oxygen were examined. Photodegradation of clofibric acid followed a pseudo-first-order kinetics model, and the rate decreased gradually with the increasing initial concentration of clofibric acid. Dissolved oxygen inhibited the photodegradation of clofibric acid. As a result of varying reaction species of clofibric acid, the initial pH conditions greatly influenced its photodegradation. Quenching experiments showed that the self-sensitization process via ·OH and 1O2 occured during photodegradation of clofibric acid, and the bimolecular reaction rate constants of clofibric acid with ·OH and 1O2 were determined via the competition kinetics method to be 3.93(±0.20) × 108 and 2.38(±0.12) × 106 L mol−1 s−1, respectively. In addition, the transformation products of clofibric acid were identified by the UPLC-Q-TOF-MS microsystem, and eight products were detected. It is proposed that the photodegradation of clofibric acid occurred mainly via decarboxylation, dechlorination, ·OH addition and 1O2 attack reaction.
研究领域:
环境科学
·
药学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Kangmeng Zhu,Xisong Wang,Mengzi Geng,Dong Chen,Heng Lin,Hui Zhang
Wood-based biochars were fabricated at different pyrolysis temperatures of 400–700 °C and used to activate peroxydisulfate (PDS) for the degradation of clofibric acid (CA). Biochar pyrolyzed at 700 °C (BC700) showed more excellent catalytic performance toward CA removal (97.8% in a 60 min reaction) than other BCs. The BC700/PDS process performed efficiently at initial pH range of 4.0–9.0. The effects of PDS concentration and BC700 dosage on CA removal were also examined. Radical quenching experiments and electron paramagnetic resonance (EPR) spectra were applied to identify the reactive radicals generated in the BC700/PDS system. The role of persistent free radicals (PFRs), oxygen functional groups and π-π * transitions in aromatic rings of BC700 for the PDS activation was explored. The reaction intermediates of CA were identified by liquid chromatography–mass spectrometry (LC–MS) and the corresponding degradation pathway was proposed. This study contributes to the development of green materials for sustainable remediation of organic contaminants in water and provides support for further studies.
研究领域:
环境科学
·
水处理技术
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Chen Chen,Shaoyuan Bai,Pengyu Liu,Dandan Xu,Xiaojie Sun,Mei Wang,Yawen Yuan
The application of electrocatalytic degradation technology in the treatment of pharmaceuticals and personal care products (PPCPs) has attracted widespread attention currently. Through structure and properties characterization of catalysts we found that more uniformly distributed metal particles and excellent thermal stability were obtained by modification with poly(1-vinyl-3-butylimidazole hexafluorophosphate) ([(PV)BIM]PF 6 ) on graphene to anchor the metal CoNi nanoparticles (CoNi/PILs-rGO). For assessing its application potential, the CoNi/PILs-rGO cathode in combination with Ti/RuO 2 /IrO 2 anode to set up an experimental reaction system for the electrocatalytic degradation of clofibric acid (CA) simulated wastewater. Reactor settings for experimentation are optimized, and intermediates, alterations in toxicity during degradation, and active species are detected. The results of the single-factor experiment showed that the average removal rate of CA by the cathodic compartment was 97.18 % when the conditions were optimal. Two possible pathways of degradation are deduced from the CA intermediates, one is the C-Cl bond breaking in electrochemical reduction, and the other is that the C-O bond is directly broken by anodic reactive oxygen. Toxicity tests have shown that the anode produces some by-products that are more hazardous than the original chemical, while the cathode produces a dechlorination process that is ultimately more detoxifying.
研究领域:
环境科学
·
材料科学
·
药学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2022
·
IF 4.598
Shuang Wu,Zheni Wang,Lei Wan,Chenghui Luo,Shams Ali Baig,Xinhua Xu
In the present study, Pd/Ni foam electrode was prepared by improved impregnation method for electrocatalytic hydrodechlorination (ECH) of clofibric acid (CA). The effects of complexing agent addition into the impregnation solution for the formation of Ni(OH) 2 and the ECH activity of Pd/Ni foam electrode were investigated. Results revealed that the introduction of sodium acetate (the complexing agent) greatly enhanced the ECH activity as compared to common impregnation liquid. Characterizations analyses demonstrated that the addition of sodium acetate did not change the phase of the electrode’s surface, but effectively reduced the deposition of Ni(OH) 2 . The surface morphology of the electrode was changed simultaneously by the addition of sodium acetate and the interlacing structure of Ni(OH) 2 and Pd catalyst was formed. NaAc before -Pd/Ni and NaAc after -Pd/Ni foam electrodes were used to perform ECH experiments on CA, and the combined Pd/Ni foam 15 min electrode was compared with the Pd/Ni foam 6 h electrode. After 2 h of electrolysis, the NaAc after -Pd/Ni foam electrode was found to remove the CA (∼100%) in the solution, which was 1.3 times the removal rate of the Pd/Ni foam 6 h electrode to CA and exceeded the Pd/Ni foam 15 min electrode. Findings from the present study demonstrated that adding the complexing agent into the impregnation solution can improve the ECH activity of Pd/Ni foam electrode and achieve a faster and more efficient dechlorination effect of CA.
研究领域:
环境化学
·
电化学
·
催化
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Lu Zhang,Meng Zhang,Xiaozhe Song,Hui Wang,Zhaoyong Bian
Here, we report enhancement of the photoelectrochemical (PEC) performance of MnO x /graphite-like carbon nitride (g-C 3 N 4 ) nanocomposites synthesized by one-step thermal decomposition for degradation of clofibric acid (CA). MnO x showed enhanced broadband ultraviolet–visible light regions, efficient charge generation–separation, and enhanced PEC performance when combined with g-C 3 N 4 . Photogenerated holes can be efficiently captured by introducing Mn 2+ /Mn 3+ /Mn 4+ valence band transitions. In addition to a good visible-light response, the MnO x /g-C 3 N 4 -10 (g-C 3 N 4 with 10% Mn(NO 3 ) 2 ·6H 2 O) photoanode showed enhanced photocurrent density of 0.03 × 10 −3 A cm −2 at 0.63 V vs. Ag/AgCl, which was approximately 100 times that of pristine g-C 3 N 4 . The superoxide radical and positive holes played dominant roles in PEC degradation of CA. The MnO x /g-C 3 N 4 -10 photoanode showed the highest photoelectrocatalytic performance under acidic conditions because of electrostatic attraction between the electrode and CA. The CA degradation ratio using the MnO x /g-C 3 N 4 -10 photoanode was 100% under visible light in 6 h at pH = 3. This work provides a simple and sustainable strategy to modify g-C 3 N 4 for captured holes to improve PEC degradation of CA, and it is promising for application to different materials in a variety of fields.
研究领域:
材料科学
·
环境科学
·
光化学
✓ 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）