Abstract：Graphene (GE) and N-doped graphene (N-GE) were used as the supports, the supported catalysts prepared by the impregnation (denoted as im-) and deposition-precipitation (denoted as dp-) methods were referred as im-Pd/GE, dp-Pd/GE, im-Pd/N-GE and dp-Pd/N-GE. The catalysts were characterized by elemental analyser, transmission electron microscope and X-ray photoelectron spectrometer. The liquid phase catalytic hydrodechlorination of 2,4-dichlorophenol (2,4-DCP) were carried out over these catalysts. The nitrogen content was 11.3% in the N-doping catalyst. Compared with Pd/GE, the N-doping catalysts displayed higher cationic Pd (Pdn+) and smaller Pd particles and exhibited higher catalytic activities. Moreover, the catalytic activities could be further improved by preparing using the deposition-precipitation method. In addition, the dechlorination of 2,4-DCP were proceeded via both the stepwise and concerted pathways.
U. S. EPA, Appendix A to 40CFR, Part 423-126Priority Pollutants, 2012.
[3]
Moritz M, Geszke-Moritz M. Application of nanoporous silicas as adsorbents for chlorinated aromatic compounds:a comparative study[J]. Materials Science & Engineering C, 2014,41:42-51.
[4]
Felis V, Fouilloux P, Bellefon C, et al. Three step catalytic detoxification process of wastewater containing chlorinated aromatic compounds:experimental results and modeling issues[J]. Industrial & Engineering Chemistry Research, 1999,38:4213-4219.
[5]
Suryaman D, Hasegawa K. Biological and photocatalytic treatment integrated with separation and reuse of titanium dioxide on the removal of chlorophenols in tap water[J]. Journal of Hazardous Materials, 2010,183:490-496.
[6]
Hozalski R, Zhang Li, Arnold W. Reduction of haloacetic acids by Fe0:implications for treatment and fate[J]. Environmental Science & Technology, 2001,35:2258-2263.
[7]
Li T Y, Chen Y M, Wan P Y, et al. Chemical degradation of drinking water disinfection byproducts by millimeter-sized particles of iron-silicon and magnesium-aluminum alloys[J]. Journal of the American Chemical Society, 2010,132:2500-2501.
[8]
Bahri A, Calvo L, Polo A, et al. Identification of by-products and toxicity assessment in aqueous-phase hydrodechlorination of diuron with palladium on activated carbon catalysts[J]. Chemosphere, 2013,91:1317-1323.
[9]
Chen H, Xu Z Y, Wan H Q, et al. Aqueous bromate reduction by catalytic hydrogenation over Pd/Al2O3 catalysts[J]. Applied Catalysis B:Environmental, 2010,96:307-313.
Gomez-Sainero L, Seoane X, Fierro J, et al. Liquid-phase hydrodechlorination of CCl4 to CHCl3 on Pd/carbon catalysts:nature and role of Pd active species[J]. Journal of Catalysis, 2002,209:279-288.
[13]
Babu S, Pasha N, Kumar V, et al. Influence of particle size and nature of Pd species on the hydrodechlorination of chloroaromatics:studies on Pd/TiO2 catalysts in chlorobenzene conversion[J]. Catalysis Today, 2009,141:120-124.
[14]
Zhou J, Wu K, Wang W J, et al. Pd supported on boron-doped mesoporous carbon as highly activecatalyst for liquid phase catalytichydrodechlorination of 2,4-dichlorophenol[J]. Applied catalysis A:Genernal, 2014,470:336-343.
[15]
Liu Q, Cui Z M, Ma Z, et al. Highly active and stable material for catalytic hydrodechlorination using ammonia-treated carbon nanofibers as Pd supports[J]. Journal of Physical Chemistry C, 2008,112:1199-1203.
[16]
Tang L H, Wang Y, Li Y M, et al. Preparation, structure, and electrochemical properties of reduced grapheme sheet films[J]. Advanced Functional Materials, 2009,19:2782-2789.
Kim Y, Noh Y, Lim Eun J, et al. Star-shaped Pd@Pt core-shell catalysts supported on reduced grapheme oxide with superior electrocatalytic performance[J]. Journal of Materials Chemistry A, 2014,2:6976-6986.
[19]
杨鑫.磁性石墨烯复合材料对环境污染物的去除与机理研究[D]. 合肥:中国科学院大学, 2013.
[20]
Yuan G, Keane M. Liquid phase hydrodechlorination of chlorophenols over Pd/C and Pd/Al2O3:A consideration of HCl/catalyst interactions and solution pH effects[J]. Applied Catalysis B:Environmental, 2004,52:301-314.
[21]
Chizari K, Janowska I, Houlle Matthieu, et al. Tuning of nitrogen-doped carbon nanotubes as catalyst support for liquidphase reaction[J]. Applied catalysis A:General, 2010,380:72-80.
[22]
Powell C J, Jablonski A, Naumkin A, et al. NIST data resources for surface analysis by X-ray photoelectron spectroscopy and Auger electron spectroscopy[J]. Journal of Electron Spectroscopy and Related Phenomena, 2001,114-116:1097-1102.
[23]
Yuan G, Keane M. Aqueous-phase hydrodechlorination of 2,4-dichlorophenol over Pd/Al2O3:Reaction under controlled pH[J]. Industrial & Engineering Chemistry Research, 2007, 46(3):705-715.
[24]
Zhou J, Han Y X, Wang W J, et al. Reductive removal of chloroacetic acids by catalytic hydrodechlorination over Pd/ZrO2 catalysts[J]. Applied Catalysis B:Environmental, 2013,134-135:222-230.
[25]
Omar S, Palomar J, Gomez-Sainero L, et al. Density functional theory analysis of dichloromethane and hydrogen interaction with Pd Clusters:first step to simulate catalytic hydrodechlorination[J]. Journal of Physical Chemistry C, 2011,115:14180-14192.
[26]
Shao Y, Xu Z Y, Wan H Q, et al. Enhanced liquid phase catalytic hydrodechlorination of 2,4-dichlorophenol over mesoporous carbon supported Pd catalysts[J]. Catalysis Communication, 2011, 12:1405-1409.
