JOURNAL OF HAZARDOUS MATERIALS
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2018
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IF 6.434
Zimo Lou,Yizhou Li,Jiasheng Zhou,Kunlun Yang,Yuanli Liu,Shams Ali Baig,Xinhua Xu
Titanium carbide (TiC) with excellent electrical conductivity, chemical and thermal stabilities has been recognized as one of the most promising electrocatalysts. A novel cathode, titanium carbide doped palladium/nickel foam (TiC-Pd/Ni foam), was synthesized via electroless deposition to improve the performance of Pd/Ni foam in electrocatlytic hydrodechlorination (ECH). TiC can be co-precipitated onto the surface of cathode during galvanic replacement reaction between Pd(II) solution and Ni foam. Both constant potential and constant current tests proved that TiC-Pd/Ni foam cathode performed remarkably higher activity for 2,4-dichlorobenzoic acid (2,4-DCBA) than Pd/Ni foam cathode, owing to the excellent conductivity of TiC and enhanced water dissociation over TiC-Pd/Ni foam cathode. Under the optimized reaction conditions of –0.85 V ( vs Ag/AgCl), electrolyte of 10 mM and initial pH of 4, 99.8% of aqueous 2,4-DCBA (0.2 mM) was removed within 90 min. The removal process of the aqueous 2,4-DCBA obeyed first-order decay kinetic model. Over 86.3% of 2,4-DCBA can still be removed by TiC-Pd/Ni foam cathode in the fifth consecutive run within 120 min, which was much higher than that of Pd/Ni foam cathode (37.5%). Consequently, TiC-Pd/Ni foam cathode was a promising design for enhanced ECH activity and reduced operation cost.
研究领域:
环境科学
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材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2022
·
IF 10.753
Xiao-Qiu Lin,Jia-Mei You,Ling-Yu Meng,Naoko Yoshida,Jing-Long Han,Cong-Ju Li,Ai-Jie Wang,Zhi-Ling Li
Tetrabromobisphenol A (TBBPA), a hazardous and persistent flame retardant , has been widely detected in the natural aquatic system. The acceleration of reductive debromination (rate-limiting process) is vital during the decomposition and detoxification of TBBPA. This study achieved superior TBBPA electrochemical reductive debromination performance by nano Pd doped Ni foam electrode (4.8 times higher than Ni foam electrode). The optimal TBBPA reductive debromination performance was obtained under −1.2 V of cathode potential, 1.2 wt% of Pd loading, 10 mg L −1 of TBBPA and 100 mM of Na 2 SO 4 as the electrolyte solution. UPLC-QTOF-MS verified that Br atoms in TBBPA were removed sequentially to form bisphenol A as the major product. Most TBBPA was reductively debrominated by atomic H* through indirect hydrodebromination, evidenced by the atomic H* quenching test. The higher solution conductivity and appropriate TBBPA concentration would contribute to the debromination efficiency. Excessive H 2 generation whether by over negative potential or H atom richness electrolyte largely disturbed the reaction process and restricted the debromination. The improved generation of reductant (H*) ads Pd was the most significant, while excessive Pd loading would make aggregation and limit the debromination efficiency. The study confirmed the optimization strategies of conditions for Pd/Ni foam electrode and revealed the related function mechanism for stimulating TBBPA electrochemical reduction, giving suggestions for the efficient removal of TBBPA in the aquatic environment.
研究领域:
环境科学
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电化学
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污染控制
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2015
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IF 4.321
Chen Sun,Zimo Lou,Yu Liu,Ruiqi Fu,Xiaoxin Zhou,Zhen Zhang,Shams Ali Baig,Xinhua Xu
In this study, nanosized titanium nitride (nTiN) doped palladium/nickel (Pd/Ni) foam electrodes were prepared via electroless deposition method for the dechlorination of 2,4-dichlorophenoxyacetic acid (2,4-D). Characterization analyses including field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX) and transmission electron microscopy (TEM) revealed that nTiN was successfully doped onto the electrode surface. 2,4-D was first dechlorinated to intermediate products p -chlorophenoxyacetic acid ( p -CPA) or o -chlorophenoxyacetic acid ( o -CPA) and then to the final product, phenoxyacetic acid (PA). The effects of environmental factors including initial 2,4-D concentration, current density, reaction temperature and dissolved anions were also studied. High initial 2,4-D concentration increased the efficient utilization of active hydrogen atom [H] by nTiN doped Pd/Ni foam electrodes. Increases in current density promoted better dechlorination efficiency while the hydrogen evolution side reaction was undesirably increased, leading to a lower average current efficiency. Higher reaction temperature was proved to be favorable for the enhancement of dechlorination efficiency. NO 3 − and reduced sulfur compounds including S 2− and SO 3 2− showed negative impacts on Pd catalytic capability, whereas CO 3 2− and Cl − exhibited less adverse effects on dechlorination efficiency. The activation energy ( E a) value of 2,4-D dechlorination by nTiN doped Pd/Ni foam electrode was calculated to be 32.06 kJ mol −1 . Two typical stages namely electrode activation and efficient dechlorination procedures occurred in 2,4-D dechlorination by nTiN doped Pd/Ni foam electrodes. The reaction paths of [H] on the electrode were also summarized. The removal efficiency of 2,4-D dechlorination on nTiN doped Pd/Ni foam electrodes was observed to slightly decrease from 100% to 89.95% after 5 consecutive experiments.
研究领域:
环境科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2019
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IF 8.355
Kejian Li,Yang Yang,Aziz-Ur-Rahim Bacha,Yiqing Feng,Saira Ajmal,Iqra Nabi,Liwu Zhang
Halogenated organic compounds (HOCs) like chlorophenols (CPs) are one of persistent organic pollutants in environment, and it is an urgent issue to remove HOCs efficiently because they are detrimental to aquatic organisms and human beings. Electrocatalytic hydrodechlorination (ECH) technique has been widely studied to deal with chlorophenols. However, litter attention has been paid to the further treatment of the dechlorination product phenol. Meanwhile, photoelectrocatalysis is regarded as a promising method for contaminants elimination and water splitting using inexhaustible solar energy. Therefore, this study proposed a photoelectrochemical reductive hydrodechlorination and sequential oxidation method for thorough degradation of 2,4-dichlorophenol (2,4-DCP) using WO 3 /Mo-doped BiVO 4 as photoanode and Pd/Ni foam as cathode. Several factors such as Pd-loading amount, initial pH, overpotential, and Cl − that would influence the efficiency of 2,4-DCP hydrodechlorination and phenol oxidation have been investigated in detail. The 2,4-DCP could be completely hydrodechlorinated to phenol, and removal efficiency of the obtained phenol reached ~45% for 4 h reaction under optimized conditions. Additionally, there was no secondary chlorinated pollutant generated during the oxidation process even though the existence of Cl − . Lastly, the possible mechanism and degradation pathway were also explored based on LC-MS. This study proposed an efficient and environmental-friendly technique for complete degradation of chlorophenols, which might be also suitable for other HOCs and would be industrialized with the help of further studies.
研究领域:
环境科学
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电化学工程
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2014
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IF 6.007
Chen Sun,Shams Ali Baig,Zimo Lou,Jin Zhu,Zhuoxing Wang,Xia Li,Jiahan Wu,Yifu Zhang,Xinhua Xu
Nanosized titanium nitride (nTiN) doped palladium/nickel (Pd/Ni) foam electrodes were successfully prepared via electroless deposition method. The electrodes were evaluated by different techniques including field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and linear sweep voltammetry (LSV). FE-SEM images demonstrated that two different morphologies existed in the Pd layer after nTiN doping. The nTiN doped Pd/Ni foam electrodes were found to be highly effective for electrochemical reductive dechlorination of 2,4-dichlorophenoxyacetic acid (2,4-D) with excellent activity and stability, as revealed by batch experiments. Under the conditions of nTiN doping content of 2 mg, Pd loading of 0.44 mg cm −2 , the energetic electrode achieved nearly 100% removal of 2,4-D (0.226 mmol L −1 ) within 2 h at a current density of 1.667 mA cm −2 . However, the removal efficiency reached only 57.13% when a normal Pd/Ni foam electrode with identical Pd loading and current density was utilized. A successive 2,4-D reductive dechlorination process was observed. o -Chlorophenoxyacetic acid ( o -CPA), p -chlorophenoxyacetic acid ( p -CPA) and phenoxyacetic acid (PA) were detected and identified as transformation products. Regression analysis proved that the pseudo-first order kinetic model was not suitable to describe the dechlorination process on nTiN doped Pd/Ni foam electrodes due to the appearance of a plateau in the beginning of the curve. Moreover, an adsorption theory for Pd chemisorption of active hydrogen atom was proposed to better explain the phenomenon. An adsorption equilibrium of hydrogen existed in the Pd lattice between hydrogen in Pd solid solution and hydrogen in metal hydride, which would influence the effective utilization of active hydrogen atom [H] for dechlorination treatment. An indirect reduction mechanism of the 2,4-D dechlorination on the as-prepared electrodes was also elucidated.
研究领域:
环境科学
·
电化学
·
污染控制
✓ 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）