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Title: Noble-metal-free bimetallic alloy nanoparticle-catalytic gasification of phenol in supercritical water

Abstract

The exploration of non-noble-metal catalysts for high efficiency gasification of biomass in supercritical water (SCW) is of great significance for the sustainable development. A series of Ni–M (M = Co or Zn) bimetallic nanoparticles supported on graphitized carbon black were synthesized and examined as catalysts for gasification of phenol in SCW. We found that a nearly complete gasification of phenol can be achieved even at a low temperature of 450 °C with the bimetallic nanoparticles catalysts. Kinetic study indicated the activation energy for phenol gasification were 20.4 ± 2.6 and 43.6 ± 2.6 kJ/mol for Ni20Zn15 and Ni20Co15 catalyst, respectively. Furthermore, XRD, XPS and TEM were performed to characterize the catalysts and the results showed the formation of NiCo and NiZn alloy phase. Catalyst recycling experiments were also conducted to evaluate the stability of the catalysts. The characterization of used catalysts suggest that the severe agglomeration of nanoparticles leads to the decrease in catalytic activity.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1347958
Grant/Contract Number:
AC05-76RL01830; 51568067; 21307049; U1137603; 1319880237
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Supercritical Fluids
Additional Journal Information:
Journal Volume: 126; Journal Issue: C; Journal ID: ISSN 0896-8446
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; phenol; supercritical water; gasification; bimetallic nanoparticle; alloy

Citation Formats

Jia, Lijuan, Yu, Jiangdong, Chen, Yuan, Ning, Ping, Guan, Qingqing, Gu, Junjie, Miao, Rongrong, and Chen, Qiuling. Noble-metal-free bimetallic alloy nanoparticle-catalytic gasification of phenol in supercritical water. United States: N. p., 2017. Web. doi:10.1016/j.supflu.2017.02.017.
Jia, Lijuan, Yu, Jiangdong, Chen, Yuan, Ning, Ping, Guan, Qingqing, Gu, Junjie, Miao, Rongrong, & Chen, Qiuling. Noble-metal-free bimetallic alloy nanoparticle-catalytic gasification of phenol in supercritical water. United States. doi:10.1016/j.supflu.2017.02.017.
Jia, Lijuan, Yu, Jiangdong, Chen, Yuan, Ning, Ping, Guan, Qingqing, Gu, Junjie, Miao, Rongrong, and Chen, Qiuling. 2017. "Noble-metal-free bimetallic alloy nanoparticle-catalytic gasification of phenol in supercritical water". United States. doi:10.1016/j.supflu.2017.02.017.
@article{osti_1347958,
title = {Noble-metal-free bimetallic alloy nanoparticle-catalytic gasification of phenol in supercritical water},
author = {Jia, Lijuan and Yu, Jiangdong and Chen, Yuan and Ning, Ping and Guan, Qingqing and Gu, Junjie and Miao, Rongrong and Chen, Qiuling},
abstractNote = {The exploration of non-noble-metal catalysts for high efficiency gasification of biomass in supercritical water (SCW) is of great significance for the sustainable development. A series of Ni–M (M = Co or Zn) bimetallic nanoparticles supported on graphitized carbon black were synthesized and examined as catalysts for gasification of phenol in SCW. We found that a nearly complete gasification of phenol can be achieved even at a low temperature of 450 °C with the bimetallic nanoparticles catalysts. Kinetic study indicated the activation energy for phenol gasification were 20.4 ± 2.6 and 43.6 ± 2.6 kJ/mol for Ni20Zn15 and Ni20Co15 catalyst, respectively. Furthermore, XRD, XPS and TEM were performed to characterize the catalysts and the results showed the formation of NiCo and NiZn alloy phase. Catalyst recycling experiments were also conducted to evaluate the stability of the catalysts. The characterization of used catalysts suggest that the severe agglomeration of nanoparticles leads to the decrease in catalytic activity.},
doi = {10.1016/j.supflu.2017.02.017},
journal = {Journal of Supercritical Fluids},
number = C,
volume = 126,
place = {United States},
year = 2017,
month = 8
}

Journal Article:
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  • H{sub 2} storage, in the form of liquid organic hydrides, e.g., methylcyclohexane (MCH), was proposed for the seasonal storage of electricity. A catalytic membrane reactor (CMR) containing a catalyst bed and a tubular palladium-silver (Pd-Ag) membrane to separate the coproduced H{sub 2}, was used to obtain higher than equilibrium conversions in the dehydrogenation of methylcyclohexane (MCH). A monometallic, Pt/Al{sub 2}O{sub 3} (MM30S), and a bimetallic, Pt-Re/Al{sub 2}O{sub 3} (BM30), noble-metal catalysts and two membranes with 0.1 and 0.2 mm wall thickness were employed. Experiments in the CMR at 573--673 K, 1--2 MPa, and liquid hourly space velocities (LHSVs) up tomore » 12 volume feed/(h{times}reactor volume) showed that catalyst MM30S was outstanding in performance giving significant improvement in toluene (TOL) and H{sub 2} yields over the equilibrium values at commercially relevant conditions. Catalyst BM30 deactivated exceeding equilibrium yields to extents considerably lower than those with catalyst MM30S. However, the ratios of H{sub 2} permeation to generation rates were almost equal for the two catalysts under comparable conditions. The extent by which the equilibrium conversions were exceeded, decreased as the LHSV increased due to permeation limited operation. Reactor axial temperature profiles showed the existence of two cold spots in the CMR. An attempt is made to correlate the extent of MCH conversion to TOL in the CMR with the operating variables.« less
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  • A kinetic analysis was made for the phenol disappearance rate in catalytic oxidation of phenol over MnO{sub 2} in supercritical water at a fixed temperature of 425 C and pressures between 22.7 and 27.2 MPa. The nonsupported MnO{sub 2} catalyst possessed a strong activity for promoting phenol oxidation, though the overall reaction rate was appreciably influenced by internal mass-transfer resistance. From the kinetic analysis on the reaction rate of the phenol disappearance, the global rate expression of the surface reaction was obtained, where the reaction orders with respect to phenol, oxygen, and water were almost unity, 0.7, and {minus}2.0, respectively.more » A Langmuir-type mechanism, in which phenol and oxygen adsorbed on the catalytic sites and water adsorbed on the same site to inhibit the phenol and oxygen adsorption, was proposed to explain the reaction orders for phenol, oxygen, and water.« less
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