TY - JOUR
T1 - Reductive destruction of multiple nitrated energetics over palladium nanoparticles in the H2-based membrane catalyst-film reactor (MCfR)
AU - Zheng, Chen Wei
AU - Long, Min
AU - Luo, Yi Hao
AU - Long, Xiangxing
AU - Bi, Yuqiang
AU - Zhou, Dandan
AU - Zhou, Chen
AU - Rittmann, Bruce E.
N1 - Publisher Copyright:
© 2021 Elsevier B.V.
PY - 2022/2/5
Y1 - 2022/2/5
N2 - Nitrated energetics are widespread contaminants due to their improper disposal from ammunition facilities. Different classes of nitrated energetics commonly co-exist in ammunition wastewater, but co-removal of the classes has hardly been documented. In this study, we evaluated the catalytic destruction of three types of energetics using palladium (Pd0) nano-catalysts deposited on H2-transfer membranes in membrane catalyst-film reactors (MCfRs). This work documented nitro-reduction of 2,4,6-trinitrotoluene (TNT), as well as, for the first time, denitration of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and pentaerythritol tetranitrate (PETN) over Pd0 at ambient temperature. The catalyst-specific activity was 20- to 90-fold higher than reported for other catalyst systems. Nitrite (NO2−) released from RDX and PETN also was catalytically reduced to dinitrogen gas (N2). Continuous treatment of a synthetic wastewater containing TNT, RDX, and PETN (5 mg/L each) for more than 20 hydraulic retention times yielded removals higher than 96% for all three energetics. Furthermore, the concentrations of NO2− and NH4+ were below the detection limit due to subsequent NO2− reduction with > 99% selectivity to N2. Thus, the MCfR provides a promising strategy for sustainable catalytic removal of co-existing energetics in ammunition wastewater.
AB - Nitrated energetics are widespread contaminants due to their improper disposal from ammunition facilities. Different classes of nitrated energetics commonly co-exist in ammunition wastewater, but co-removal of the classes has hardly been documented. In this study, we evaluated the catalytic destruction of three types of energetics using palladium (Pd0) nano-catalysts deposited on H2-transfer membranes in membrane catalyst-film reactors (MCfRs). This work documented nitro-reduction of 2,4,6-trinitrotoluene (TNT), as well as, for the first time, denitration of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and pentaerythritol tetranitrate (PETN) over Pd0 at ambient temperature. The catalyst-specific activity was 20- to 90-fold higher than reported for other catalyst systems. Nitrite (NO2−) released from RDX and PETN also was catalytically reduced to dinitrogen gas (N2). Continuous treatment of a synthetic wastewater containing TNT, RDX, and PETN (5 mg/L each) for more than 20 hydraulic retention times yielded removals higher than 96% for all three energetics. Furthermore, the concentrations of NO2− and NH4+ were below the detection limit due to subsequent NO2− reduction with > 99% selectivity to N2. Thus, the MCfR provides a promising strategy for sustainable catalytic removal of co-existing energetics in ammunition wastewater.
KW - Denitration
KW - Hollow fiber membrane
KW - Membrane catalyst-film reactor
KW - Nitrated energetics
KW - Palladium catalysis
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U2 - 10.1016/j.jhazmat.2021.127055
DO - 10.1016/j.jhazmat.2021.127055
M3 - Article
C2 - 34523494
AN - SCOPUS:85114413484
SN - 0304-3894
VL - 423
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
M1 - 127055
ER -