ADSORPTION SCIENCE & TECHNOLOGY
·
2020
·
IF 2.425
Qiaoling Xie,Gaojie Liang,Tao Lin,Fuming Chen,Dandan Wang,Bo Yang
A study on selective chelating precipitation of palladium metal from real electroplating wastewater using chitosan and its water-soluble derivative was conducted. The pH parameter, the concentrations of chitosan and its water-soluble derivative and the chelating precipitation time were experimentally investigated, and the optimum conditions were determined. The results revealed that both chitosan and its water-soluble derivative acted as chelating precipitation agents. Rapid chelating precipitation occurred when chitosan was added to real electroplating wastewater containing the chitosan derivative, thereby improving removal efficiency of palladium in different forms up to 95% under the optimum condition of 0.2 g/L chitosan and 0.16 mg/L derivative at pH 2.5. Then, dissolution experiments showed that chelating precipitation products could be dissolved in aqua regia. Additionally, selective chelating precipitation of palladium by chitosan and its derivative was characterized using X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. Thus, it can be concluded that the combined utilization of chitosan and its water-soluble derivative is a promising approach method for the removal of different forms of palladium from real electroplating wastewater.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
RSC Advances
·
2020
·Vol. 11
·期 1
·48-56
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IF 3.119
Yingjie Hu,Yuxin Mei,Baining Lin,Xuhong Du,Fan Xu,Huasheng Xie,Kang Wang,Yonghua Zhou
The one-pot synthesis of methyl isobutyl ketone (MIBK) and methyl isobutyl methanol (MIBC) from acetone and hydrogen is a typical cascade reaction comprised of aldol condensation-dehydration-hydrogenation. Pd loss and aggregation during long term operation are typical problems in industrial application. In this paper, an active and stable catalyst was achieved with defective UiO-66 as a support for Pd, which was synthesized with the ratio 15 : 1 of ZrOCl2·8H2O to ZrCl4 as Zr-precursors. The resultant Pd catalyst remained active for at least 1000 h with a MIBK + MIBC selectivity of 84.87–93.09% and acetone conversion of 45.26–53.22% in a continuous trickle-bed reactor. Besides the increased Brønsted acid amount generated by the defect sites was favorable for the activity, the cavity confinement in the UiO-66 (R = 15 : 1) structure also efficiently prevented Pd loss and aggregation during the long term run. The contrast of the characterization of the fresh and used Pd/UiO-66 (R = 15 : 1) indicated that the deactivation of the catalyst was attributed to carbonaceous accumulation on the catalyst surface, which could be easily regenerated by calcination. This work supplied a new alternative for the design and utilization of industrial catalysts for MIBK and MIBC synthesis.
研究领域:
催化化学
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材料科学
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产品关联
DOI
PubMed
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
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2018
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IF 2.21
Bing Zhang,Likang Fu,Shixing Wang,Libo Zhang
Nanosilica was functionalized with imidazoline groups and used as a new sorbent to recycle Pd(II) from aqueous solution. The sorbent was investigated by thermogravimetric analysis (TGA), transmission electron microscopy (TEM), fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS). The influence of pH, adsorption time and original Pd(II) concentration on recovery was discussed. The optimal pH value for adsorption was 4. The maximum adsorption quantity of Pd(II) was 69.6 mg/g. The coexisting ions exhibit little interference on the Pd(II) separation. The separation process of Pd(II) matches a pseudo-second-order kinetic model. The separation data obeyed best with the Langmuir isotherm model. The adsorbent exhibited good recyclability for Pd(II). Separation of Pd(II) takes place via chelation and ion-exchange. The adsorbent has wide application prospect to selectively capture Pd(II) from aqueous solutions.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2020
·
IF 6.551
Jirui Yang,Xinhua Qi,Feng Shen,Mo Qiu,Richard Lee Smith
Transfer hydrogenation is highly effective for dechlorinating priority organic pollutants in wastewater. Lindane could be completely dechlorinated at room temperature and atmospheric pressure via transfer hydrogenation, in which Pd (3.1 wt%) supported on chitosan-derived porous carbon (3.1Pd@A600) and formic acid (FA) were used as catalyst and hydrogen source, respectively. Favorable catalytic activity of 3.1Pd@A600 is attributed to pyridinic N of the support that allowed Pd nanoparticles to be well-dispersed in the solid and to pyridinic N-Pd interactions that enhanced FA decomposition over that observed for commercial carbon supported Pd catalyst (5Pd@AC). In the reaction system containing 3.1Pd@A600 and FA, 99.7% lindane conversion and 100% dechlorination efficiency could be achieved at 25 °C and atmospheric pressure within 60 min. Benzene and cyclohexane were identified as end-products of lindane dechlorination . The transfer hydrogenation strategy developed in this study has wide application to chlorinated organic pollutants contained in actual waste streams.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2022
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IF 7.139
Wenxin Liu,Jiabin Zou,Shuni Li,Jinkun Li,Feihu Li,Zili Zhan,Yeguang Zhang
Hydrogen sensors are easily deactivated by hexamethyldisiloxane (HMDSO) poisoning. Moreover, the existing anti-poisoning strategies can also damage the overall sensing performance of these hydrogen sensors. Therefore, a new bilayer design with a Pd/In 2 O 3 sensitive layer and an In 2 O 3 /Al 2 O 3 catalytic filter layer is proposed to avoid the deactivation of hydrogen sensors. The In 2 O 3 /Al 2 O 3 layer helps in hindering HMDSO and its decomposition products from reaching the Pd/In 2 O 3 layer. The H 2 response of the sensors is enhanced due to the small size of In 2 O 3 and the electronic sensitization of Pd. As a result, the bilayer sensors exhibit high response (Ra/Rg = 53) and ultra-fast response time (1 s) towards 3000 ppm H 2 at 365 °C. The resistance and the H 2 response of the bilayer sensors are almost unchanged after 40 min of 10 ppm HDMSO poisoning. In this paper, the mechanism of resistance against silicone poisoning and the H 2 response of the bilayer sensors are discussed from the separation of sensing and catalytic filtration reactions to the behavior of adsorbed oxygen.
研究领域:
材料科学
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传感器技术
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DOI
高影响因子
Catalysts
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2015
·Vol. 5
·期 3
·1388-1398
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IF 2
Long-Long Wang,Xiao-Lu Cao,Ya-Jun Wang,Qiao-Xia Li
The newly proposed mimetic underpotential deposition (MUPD) technique was extended to modify Pd surfaces with Sb through immersing a Pd film electrode or dispersing Pd/C powder in a Sb(III)-containing solution blended with ascorbic acid (AA). The introduction of AA shifts down the open circuit potential of Pd substrate available to achieve suitable Sb modification. The electrocatalytic activity and long-term stability towards HCOOH electrooxidation of the Sb modified Pd surfaces (film electrode or powder catalyst) by MUPD is superior than that of unmodified Pd and Sb modified Pd surfaces by conventional UPD method. The enhancement of electrocatalytic performance is due to the third body effect and electronic effect, as well as bi-functional mechanism induced by Sb modification which result in increased resistance against CO poisoning.Keywords:formic acid oxidation;palladium;Sb modification;mimetic underpotential deposition
研究领域:
电化学
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催化材料
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DOI
高影响因子
Nano Research
·
2017
·Vol. 10
·期 10
·3396-3406
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IF 7.354
Zhu Yuzhen,Gao Chao,Bai Song,Chen Shuangming,Long Ran,Song Li,Li Zhengquan,Xiong Yujie
Photocatalytic reduction of CO 2 into high value-added CH 4 is a promising solution for energy and environmental crises. Integrating semiconductors with cocatalysts can improve the activities for photocatalytic CO 2 reduction; however, most metal cocatalysts mainly produce CO and H 2 . Herein, we report a cocatalyst hydridation approach for significantly enhancing the photocatalytic reduction of CO 2 into CH 4 . Hydriding Pd cocatalysts into PdH 0.43 played a dual role in performance enhancement. As revealed by our isotopic labeling experiments, the PdH 0.43 hydride cocatalysts reduced H 2 evolution, which suppressed the H 2 production and facilitated the conversion of the CO intermediate into the final product: CH 4 . Meanwhile, hydridation promoted the electron trapping on the cocatalysts, improving the charge separation. This approach increased the photocatalytic selectivity in CH 4 production from 3.2% to 63.6% on Pd{100} and from 15.6% to 73.4% on Pd{111}. The results provide insights into photocatalytic mechanism studies and introduce new opportunities for designing materials towards photocatalytic CO 2 conversion.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
CELLULOSE
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2017
·Vol. 24
·期 6
·2403-2413
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IF 3.417
Xu Siquan,Yan Xiaopei,Bu Quan,Xia Haian
A series of carbon nanotube (CNT)-supported monometallic Pd and bimetallic Pd–Fe catalysts were synthesized and employed for catalytic hydrogenolysis of cellulose into polyols, including hexitol, ethylene glycol (EG), 1,2-propanediol (1,2-PG), and glycerol (Gly). The physicochemical properties of the catalysts were characterized by nitrogen physical adsorption measurements, X-ray diffraction analysis, transmission electron microscopy, and X-ray photoelectron spectroscopy. The total yield of hexitol, EG, 1,2-PG, and Gly in hydrolytic hydrogenation of cellulose was 37, 55, and 53% for Pd/CNTs, Pd–Fe/CNTs (Pd:Fe = 1:1), and Pd–Fe/CNTs (Pd:Fe = 1:2), respectively. Addition of Fe to Pd significantly modified the physicochemical properties of the nanoparticles and their catalytic performance, especially regarding hexitol selectivity. The promoting effect of Fe, especially for hexitol selectivity, compared with the monometallic catalyst is due to the fact that incorporation of Fe may stabilize Pd 0 nanoparticles and lead to downshift of the d -band center of Pd metal nanoparticles by charge transfer from Fe to Pd. Recycling experimental results showed that leaching of Fe resulted in a significant decrease in the hexitol yield obtained using the Pd–Fe/CNTs after the first recycle, further demonstrating that Fe element plays a promoting role for hexitol formation.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
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2021
·Vol. 28
·期 47
·67098-67107
·
IF 4.223
Long Yingtao,Liang Jianjun,Xue Yinghao
A novel composite (nZVI/Pd-AC) was prepared by loading nanoscale zero-valent iron (nZVI) and Pd on activated carbon (AC) electrode under electrodeposition with ultrasound, which was used to reductive degradation of methylene blue (MB). The loading contents of Fe and Pd in composite materials were 15.84% and 2.06%, respectively. XPS results further confirmed that the as-prepared material contained Fe 0 and Pd 0 . Without external conditions, MB could be degraded in the presence of nZVI/Pd-AC and reached equilibrium within 180 min. To investigate the reusability, the re-electrodeposition strategy was effective to refresh the active sites of nZVI/Pd-AC, and the removal efficiency only reduced by 4.51% in five circles indicating the good reusability of nZVI/Pd-AC composites. GC–MS was used to identify possible degradation pathways of MB; the results showed that the degradation products were mainly N, N-dimethylaniline and 2-amino-5-dimethylamino-benzenesulfonic acid. And the S–C, C–N bonds are the sites easier to be attacked. Graphical abstract
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
CHEMOSPHERE
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2021
·
IF 7.086
Yuan Chen,Yuancai Chen,Jianbo Jia,Bing Yan
The present study focuses on the successful preparation of microbial palladium nanoparticles (Pd-NPs). The even distribution of Pd in the periplasmic space of B. megaterium Y-4 cells is characterized using a transmission electronic microscopy (TEM) and scanning electron microscope (SEM). X-Ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) revealed the domination of Pd (0) in Pd-NPs. The microbial Pd-NPs were selected to detoxify triclosan (TCS). Liquid chromatography-mass spectrometry (LC-MS) was used to analyze the intermediate products of dechlorination and oxidization. Free radicals quenching and 5,5-dimethyl-1-pyrroline N-oxide (DMPO) capturing experiments confirmed the crucial contribution of atomic H• and O 2 ·– to TCS degradation. Besides, TCS degradation by microbial Pd-NPs could alleviate the cytotoxicity of TCS polluted water. Meanwhile, great circulating utilization of microbial Pd-NPs was obtained in degrading TCS. Corresponding findings in the present study could provide new insight into the role of microbial Pd-NPs in detoxifying pollutants.
研究领域:
环境科学
·
微生物学
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DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2022
·
IF 24.319
You Xu,Kaili Ren,Tianlun Ren,Mingzhen Wang,Ziqiang Wang,Xiaonian Li,Liang Wang,Hongjing Wang
Electrochemical reduction of nitrate (NO 3 - ) to ammonia (NH 3 ) offers a sustainable avenue to close the NO 3 - cycle for NH 3 synthesis. Critical to the feasibility of electrochemical NO 3 - -to-NH 3 technology is the development of cost-effective, scalable and selective catalysts that can produce NH 3 with high yield. To this end, we design and constructure ultralow-content Pd (2.93 at%) in-situ incorporated Cu 2 O corner-etched octahedra (Pd-Cu 2 O CEO) with cavity and oxygen vacancy defects for selectively electrochemical NO 3 - -to-NH 3 transformation. The unique conner-etched cavity structure, rich surface oxygen vacancies, and Pd-Cu 2 O dual active sites, synergistically promote nitrate electroreduction undergo ammonia formation reaction pathway. Impressively, the as-made Pd-Cu 2 O CEO exhibited outstanding activity for electrocatalytic NO 3 - -to-NH 3 , with high ammonia selectivity (95.31%) and Faradaic efficiency (96.56%). The developed hierarchical-defect strategy may open a new avenue for reasonable design of defect electrocatalysts to contribute desirable properties and functionalities in specific applications.
研究领域:
电化学催化
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材料科学
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产品关联
DOI
高影响因子
MOLECULES
·
2023
·Vol. 28
·期 5
·2335
·
IF 4.6
Hongquan Kang,Jianzhou Wu,Baohui Lou,Yue Wang,Yilin Zhao,Juanjuan Liu,Shihui Zou,Jie Fan
The rational regulation of catalyst active sites at atomic scale is a key approach to unveil the relationship between structure and catalytic performance. Herein, we reported a strategy for the controllable deposition of Bi on Pd nanocubes (Pd NCs) in the priority order from corners to edges and then to facets (Pd NCs@Bi). The spherical aberration-corrected scanning transmission electron microscopy (ac-STEM) results indicated that Bi2O3with an amorphous structure covers the specific sites of Pd NCs. When only the corners and edges of the Pd NCs were covered, the supported Pd NCs@Bi catalyst exhibited an optimal trade-off between high conversion and selectivity in the hydrogenation of acetylene to ethylene under ethylene-rich conditions (99.7% C2H2conversion and 94.3% C2H4selectivity at 170 °C) with remarkable long-term stability. According to the H2-TPR and C2H4-TPD measurements, the moderate hydrogen dissociation and the weak ethylene adsorption are responsible for this excellent catalytic performance. Following these results, the selectively Bi-deposited Pd nanoparticle catalysts showed incredible acetylene hydrogenation performance, which provides a feasible perspective to design and develop highly selective hydrogenation catalysts for industrial applications.Keywords:acetylene hydrogenation;active sites;selective deposition;palladium;bismuth
研究领域:
催化化学
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材料科学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）