2.4.6- trinitrotoluene reduction

Watrous MM, S Clark, R Kutty, S Huang, FB Rudolph, JB Hughes, GN Bennett (2003) 2,4,6-trinitrotoluene reduction by an Fe-only hydrogenase in Clostridium acetobutylicum. J Bacteriol 182 5683-5691. 

Physical (including thermochemical and explosive) properties Chemical properties of 2,4,6-trinitrotoluene Reaction with sodium sulphite Oxidation of 2,4,6-trinitrotoluene Reduction of 2,4,6-trinitrotoluene Melhylation of 2,4,6-trinitrotoluene... 

Huang S, Lindahl PA, Wang C, Bennett GN, Rudolph FB, Hughes JB. (2000). 2,4,6-trinitrotoluene reduction by carbon monoxide dehydrogenase from Clostridium thermo-aceticum. Applied and Environmental Microbiology 66 1474—1478. 

The main application of 2-nitrotoluene is its further nitration to 2,4/2,6-dinitro-toluene mixtures, which are used in the production of toluene diisocyanate. Other important secondary reactions of 2-nitrotoluene are further nitration to trinitrotoluene, reduction to 2-toluidine and the production of 2-tolidine by benzidine rearrangement. 

Mixtures of HNO, H2SO4, and SO also result in high concentrations of NO/, and toluene can be readily nitrated at —40 to — 10°C as a result (6). At these low temperatures, the formation of the meta-isomer of mononitrotoluene (MNT) is greatiy reduced. Such a reduction is highly desired in the production both of dinitrotoluenes (DNTs) employed to produce intermediates for polyurethane production and of trinitrotoluene (TNT), which is a high explosive. > -MNT results in the production of undesired DNT and TNT isomers (see Nitrobenzene and nitrotoluenes). 

The reduction of 2,4,6-trinitrotoluene with Fe° has been extensively studied (references in Bandstra et al. 2005), and it has hnally produced 2,4,6-triaminotoluene that could undergo polymerization. 

Bandstra JZ, R Miehr, RL Johnson, PG Tratnyek (2005) Reduction of 2,4,6-trinitrotoluene by iron metal kinetic controls on product distributions in batch experiments. Environ Sci Technol 39 230-238. 

Vorbeck C, H Lenke, P Fischer, JC Spain, H-J Knackmuss (1998) Initial reductive reactions in aerobic microbial metabolism of 2,4,6-trinitrotoluene. Appl Environ Microbiol 64 246-252. 

The N-labeled amines produced by partial and total reduction of the nitro groups in 2,4,6-trinitrotoluene reacted with carbonyl groups (quinones and ketones) in humic acid to produce a range of products (Thom and Kennedy 2002). 

Nitrotoluenes including 2,4,6-trinitrotoluene (TNT) are important components of explosives and several nitroarenes including the antibacterial nitrofurans have established mntagenicity (Purohit and Basu 2000). Substantial effort has been directed to the degradation of nitroarenes, and to their reduction to amines. Although nitroarene reductases, noted in Chapter 3, Part 3, are distribnted in a range of biota, the products may not necessarily represent intermediates in the degradation... 

The degradation of 2,4,6-trinitrotoluene under aerobic conditions is strictly dependent on the reduction of one or more nitro groups to amino groups before dioxygenation (Fiorella and Spain 1997 Johnson et al. 2001). 

TACOM TBA TCLP THC TNB TNBA TNT TOC TRBP TW-SCWO Tank-Automotive and Armaments Command tributylamine toxicity characteristic leaching procedure total hydrocarbons trinitrobenzene trinitrobenzoic acid trinitrotoluene (an energetic material) total organic carbon thermal reduction batch processor transpiring-wall supercritical water oxidation... 

In addition to erythrocytes, blood contains white blood cells, called leukocytes, of several types, and platelets, also called thrombocytes, which control blood clotting. Hematopoiesis (from the Greek, haimo, for blood, and poiein for to make ) is the process by which the elements of the blood are formed. The marrow of bone contains so-called stem cells which are immature predecessors of these three types of blood cells. Chemicals that are toxic to bone marrow can lead to anemia (decreased levels of erythrocytes), leukopenia (decreased numbers of leukocytes), or thrombocytopenia. Pancytopenia, a severe form of poisoning, refers to the reduction in circulatory levels of all three elements of the blood. One or more of these conditions can result from sufficiently intense exposure to chemicals such as benzene, arsenic, the explosive trinitrotoluene (TNT), gold, certain drugs, and ionizing radiation. Health consequences can range... 

Two other derivatives of toluene are the important explosive trinitrotoluene (TNT) and the polyurethane monomer toluene diisocyanate (TDI). TNT requires complete nitration of toluene. TDI is derived from a mixture of dinitrotoluenes (usually 80% o,p and 20% o,o) by reduction to the diamine and reaction with phosgene to the diisocyanate. TDI is made into flexible foam polyurethanes for cushioning in furniture (35%), transportation (25%), carpet underlay (20%), and bedding (10%). A small amount is used in polyurethane coatings, rigid foams, and elastomers. 

Nitrotoluenes, Van No strand, NY(1918) 2)M.Kostevitch, "Tarry Matter of Alpha Trinitrotoluene, Part II, Imprd Art Vol-taire,P aris( 1927), 8 3)Sidgwick( 19 37), 259 et seq 4)Davis(1943), 136-7, 147, 149-51 170-1 5>negering( 1950), 139 seq 6) Dept of the Army TM 9-1910( 1955), 146 Alkalies, Action on Nitric Esters. Organic nitrates in general are readily saponified by alkaline solns. A simple metathetical reaction to yield the alkali nitrate and alcohol does not take place instead, as a result of simultaneous oxidation and reduction, alkali nitrite and a variety of products are formed depending on the conditions of the reaction. The resistance of different nitric esters to alkalies varies considerably. Thus, starch nitrate is decomposed much more slowly than cellulose nitrate and amylopectin nitrate still more alowly... 

Figure 14.6 Reduction pathway of 2,4,6-trinitrotoluene to aminodi-nitrotoluenes (ADNTs), diamino-nitrotoluenes (DANTs), and tri-aminotoluene (TAT).

From a practical point of view, reduction of NACs is of great interest for two reasons. First, the amino compounds formed may exhibit a considerable (eco)toxi-city, and therefore may be of even greater concern as compared to the parent compounds. Additionally, the reduced products may react further with natural matrices, in particular with natural organic matter, thus leading to bound residues (see sections on oxidations below). One prominent example involves the reduction products of the explosive, 2,4,6-trinitrotoluene (TNT see Fig. 14.6), particularly the two isomeric diaminonitrotoluenes (2,4-DA-6-NT and 2,6-DA-4-NT) and the completely reduced triaminotoluene (TAT). These have been found to bind irreversibly to organic matter constituents present in soils (Achtnich et al., 2000) and sediments (Elovitz and Weber, 1999). This process offers interesting perspectives for the treatment of NAC contaminated sites. In fact, a dual step anaerobic/aerobic soil slurry treatment process has been developed for remediation of TNT contaminated soils (Lenke et al., 2000). 

Elovitz, M. S., and W. J. Weber, Sediment-mediated reduction of 2,4,6-trinitrotoluene and fate of the resulting aromatic (poly)amines , Environ. Sci. Technol., 33,2617-2625 (1999). 

Stahl, J. D. Aust, S. D. (1993a). Plasma membrane dependent reduction of 2,4,6-trinitrotoluene by Phanerochaete chrysosporium. Biochemical and Biophysical Research Communications, 192(2), 471-6. 

The denitration system works satisfactorily only for spent acid from the nitration of glycerine and similar alcohols. In spent acid from trinitrotoluene production the high content of dissolved nitrated hydrocarbons causes an excessive reduction of nitric arid at the top of the denitrating tower. Thus spent acid from the nitration... 

A.T. Nielsen et al, Reduction and Ammonoly-sis Products Derived from Isomeric Trinitrotoluenes. Synthesis and Chemical Stability of the Aminodinitrotoluenes , NWC-TP-5933, NavalWeapCenter, China Lake (1977)... 

Rate constants for superoxide ion (02 ) and its conjugate acid HOz as oxidant, reductant, and nucleophile have been measured in several solvents (Hendry and Schuetzle, 1976 Sawyer et al., 1978 Bielski et al., 1985), but few SARs have been developed. Moreover, the reactivity of superoxide ion generally is too low for the oxidant to be important in surface waters. Solvated electrons (e Aq) also form on insolation of DOM (Fischer et. al., 1985 Zepp et. al., 1988), but its concentration is very low, and target compounds are too few to make e (Aq) an important redox agent in surface waters (Buxton et al., 1988). One possible exception is nitroaromatics such as 2,4,6-trinitrotoluene (TNT), which exhibit strong acceleration of photolysis rates in the presence of DOM (Mabey et al., 1983). 

Trinitrotoluene gives analogously trinitrobenzoic acid. p-Dinitrostilbene. While carrying out some experiments on the dye sun yellow/ which is obtained by warming p-nitro-toluenesulplxonic acid with sodium hydroxide, Elbs and Kre-mann3 worked on the electrochemical reduction of several stilbene derivatives. 

For the nitrogen determination on many organic compounds, the Gunning-Amold method or modification of it has been used. The only modifications reported to be satisfactory for trinitrotoluene or other nitro-compounds are the zinc dust reduction by W. C. Cope, U. S. Bureau of Mines, and the use of nitron as reagent by W. C. Cope and J. Barub. (1)... 

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