Degradation of 2,4,6-trinitrotoluene (TNT) from explosive wastewater using nanoscale zero-valent iron

Abstract

a b s t r a c tThe degradation of 2,4,6-trinitrotoluene (TNT) in wastewater using nanoscale zero-valent iron (nZVI) was investigated. The results showed that >99% TNT was degraded when the initial TNT concentration was 80 mg L −1 after degradation for 3 h by 5 g L −1 of nZVI at pH 4, 40• C using a rotary oscillation incubator operating at 200 rpm. The Langmuir-Hinshelwood kinetics model fit the kinetics of TNT degradation by nZVI well. Fourier transform infrared (FT-IR) and ultraviolet-visible spectrophotometry showed that TNT was adsorbed on the surface of nZVI, and this reduced TNT in aqueous solution. X-ray diffraction (XRD) demonstrated that the surface of nZVI changed during the degradation of TNT.

Calcium alginate encapsulated Ni/Fe nanoparticles beads for simultaneous removal of Cu (II) and monochlorobenzene

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A modified lignin adsorbent for the removal of 2,4,6-trinitrotoluene

“…Finally the mixture was diluted to 25 mL with distilled water. TNT concentrations were measured by Shimadzu UV-3150-VIS-NIR spectrophotometer (wavelength reproducibility: ±0.1; wavelength accuracy: ±0.3 nm) at 466 nm [34] using calibration curve (linear equation: Y = 0.09052X + 0.0495, where Y is absorbency and X is TNT concentration in mg/L; R 2 = 0.999) which was established from the known concentration of standard TNT solutions (0.2 mg/L, 0.4 mg/L, 1.2 mg/L, 2.0 mg/L, 2.8 mg/L and 4.0 mg/L, respectively). The standard linear calibration curves were prepared to match closely the composition of the analyzed solutions and the linearity was ensured by Beer-Lambert law.…”

Preparation and application of novel catalytic-ceramic-filler in a coupled system for TNT manufacturing wastewater treatment

“…However, it should be noted that the removal rate of TNT decreased rapidly when DO exceeded 2.0 mg L À1 . The reason may be that oxygen could accept electrons and compete with TNT for available electrons, impeding the reduction reaction in the wastewater [27]. Therefore, DO in the wastewater should not be higher than 2.0 mg L À1 .…”