Degradation of explosives-related compounds using nickel catalysts.
We report the ability of nickel-based catalysts to degrade explosives compounds in aqueous solution. Several nickel catalysts completely degraded the explosives, although rates varied. Nearly all of the organic explosive compounds tested, including 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), were rapidly degraded to below detection limits by a powdered nickel on an alumina-silicate support (Aldrich nickel catalyst). Perchlorate degradation was minimal (<25%). Degradation of TNT by Aldrich nickel catalyst resulted in apparent first-order kinetics. Significant gaseous 14C was released and collected in an alkaline solution (most likely carbon dioxide) from [14C]RDX and [14C]HMX, indicating heterocyclic ring cleavage. Significant gaseous 14C was not produced from [14C]TNT, but spectrophotometric evidence indicated loss of aromaticity. Degradation occurred in low ionic strength solutions, groundwater, and from pH 3 to pH 9. Degradation of TNT, RDX, and HMX was maintained in flow-through columns of Aldrich nickel catalyst mixed with sand down to a hydraulic retention time of 4h. These data indicate that nickel-based catalysts may be an effective means for remediation of energetics-contaminated groundwater.
Fuller
Mark E
ME
Shaw Environmental, Inc., 17 Princess Road, Lawrenceville, NJ 08648, USA. Mark.Fuller@shawgrp.com
Schaefer
Charles E
CE
Lowey
Jean M
JM
D001392:Azocines / Q000737:chemistry; D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D052918:Environmental Restoration and Remediation / Q000379:methods*; D053834:Explosive Agents / Q000737:chemistry*; D006573:Heterocyclic Compounds, 1-Ring / Q000737:chemistry; D007700:Kinetics; D009532:Nickel / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry*; D014227:Triazines / Q000737:chemistry; D014303:Trinitrotoluene / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry*
D001392:Azocines; D053834:Explosive Agents; D006573:Heterocyclic Compounds, 1-Ring; D012989:Soil Pollutants; D014227:Triazines; D014874:Water Pollutants, Chemical; D014303:Trinitrotoluene; D009532:Nickel; C007950:octogen; C009160:cyclonite