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1

Review of the Methods for Selective Nitration of Toluene

Nastała Andrzej, Maksimowski Paweł

Central European Journal of Energetic Materials

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2023

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Vol. 20, no. 2

97--113

EN

A solution to the problems encountered with the treatment of wastewater during the industrial production of TNT could be the use of the mixture of nitrotoluenes (NTs) with no or a smaller amount of the meta-NT compared to the mixture resulting from conventional mononitration. This can be achieved by selective nitration of toluene with a nitration mixture which is more selective than conventional nitrating mixtures. This paper presents a review of the literature related to the methods for selective nitration of toluene using the following nitrating agents: nitric(V) acid, acetyl nitrate(V), nitrogen(V) oxide and others.

2

Selective Nitration of Toluene using Nitrogen(V) Oxide in Dichloromethane and Catalysts

Maksimowski Paweł, Nastała Andrzej, Tomaszewski Waldemar

Central European Journal of Energetic Materials

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2022

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Vol. 19, no. 4

424--437

EN

A series of toluene nitration reactions was carried out using a nitrogen(V) oxide (N₂O₅)solution in dichloromethane (CH₂Cl₂), with and without the addition of solid catalysts. N₂O₅ in CH₂Cl₂ was found to be a more active and selective mixture compared to 100% nitric acid and a mixture of nitric acid(V) in CH₂Cl₂. Temperature has a significant effect on the composition of the products of nitration of toluene with N₂O₅ in CH₂Cl₂; as the reaction temperature was decreased, the amount of meta-nitrotoluene decreased to approx. 1-1.2%, at a nitration temperature below -40 °C. The use of molecular sieves with toluene adsorption resulted in a quite powerful para effect, demonstrated by a significant increase in the amount of the para isomer, while reducing the ortho- and meta-isomers. The most pertinent effect was obtained when using 13X molecular sieves. In addition to improving the selectivity, the use of molecular sieves also leads to a higher degree of nitration of toluene (toluene/N₂O₅ = 1:1) due to the resulting nitric acid being absorbed by the pores of the molecular sieve.

3

Nitration of γ-Cyclodextrin

Maksimowski Paweł, Janson Agnieszka

Central European Journal of Energetic Materials

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2020

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Vol. 17, no. 3

362--383

EN

A number of γ-cyclodextrin (γ-CD) nitration reactions were conducted with different times, temperatures and types of nitrating mixtures. The degree and yield of γ-CD nitration (γ-CDN) depended on the HNO3 concentration, the type of nitrating mixture, the nitration time and, to a lesser extent, the temperature. 100% HNO3 proved to be the finest nitrating agent. By nitrating γ-CD in this system, a degree of nitration of 1, as well as a yield of 90-99% were obtained. An examination of the properties of the resulting γ-CDN served to conclude that the density and sensitivity to mechanical stimuli (friction and impact) depend on the degree of substitution of the –OH groups with –ONO2 groups. The higher the degree of γ-CD nitration, the greater the density and sensitivity to external stimuli. Thermal analysis of the γ-CDN obtained at various nitration levels demonstrated that γ-CDN with a high degree of substitution decomposes in one exothermic stage, at temperatures of approximately 184-250 °C. The lower the degree of γ-CDN nitration, the lower is the thermal effect of decomposition, with the maximum exothermic peak being shifted increasingly towards a higher temperature.

4

Nitrogen removal from ammonium-rich pharmaceutical wastewater. A comparison between sequencing batch reactor (SBR) and sequencing batch biofilm reactor (SBBR)

Hajsardar M., Borghei S. M., Hassani A. H., Takdastan A.

Environment Protection Engineering

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2018

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Vol. 44, nr 3

95--115

EN

Biological nitrogen removal from industrial wastewater (pharmaceutical synthetic wastewater) was studied. Sequencing batch reactor (SBR) and sequencing batch biofilm reactor (SBBR) were utilized to treat ammonium-rich wastewater. No external carbon source was added to the reactors. At nitrogen loading rate (NLR) of 2.5 kg N/(m3·day), the efficiency of ammonium removal from synthetic wastewater in SBR was 86.9%. SBBR ammonium removal efficiency under fixed dissolved oxygen (DO) concentration of 0.3 mg O2/dm3 was 98.4%. Specific nitrification rate (SNR) and specific denitrification rate (SDNR) in SBR were 9.24 mg NH4 +-N/(g MLVSS·h) and 18.56 mg NO3 – -N/(g MLVSS·h), respectively. Nitrite accumulation rate (NAR) showed high correlation with DO decrement (R2 = 0.983), NAR and simultaneous nitrification and denitrification (SND) had high correlation, too (R² = 0.976). SND efficiency in SBBR reached 94.1% while ammonium oxidizing bacteria (AOB) were dominant and NAR in SBBR process at the DO level of 0.3 mg O2/dm3 was 90.3%.

5

Investigation of the Radical Nitration of Isooctane Fuel via Nitromethane Propellant

Bayar C. C.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 2

225--242

EN

The possible radical nitration reactions of isooctane fuel with nitromethane propellant, which is generally used as an additive in fuel formulations, were thermodynamically investigated both at room temperature and at a higher temperature of 691.15 K. The temperature of 691.15 K was chosen because it is the auto-ignition temperature of isooctane and nitromethane and has the potential to mimic better engine conditions. The computational calculations were performed at the theoretical level of DFT UB3LYP/cc-pVDZ. Four different nitration reactions and nitrated products were considered and interpreted in detail. The most and the least favorable nitrations were observed at the primary and secondary carbons of isooctane at 691.15 K, respectively. Four of the designated reactions were endothermic at this temperature. The other outcome of this study was that there was a direct relationship between the thermodynamic tendencies of the considered reactions and the ballistic performances (detonation velocities, detonation pressures, and specific impulses) of their nitrated products. The thermodynamic properties of heats of combustion and deflagration temperatures were calculated via empirical formulations based on the stoichiometry and some other structural parameters of the energetic materials. The results for nitromethane and the nitro-isooctane products were examined.

6

New Synthetic Methods for 4,4’,5,5’-Tetranitro-2,2’-bi- 1H-imidazole (TNBI)

Szala M., Lewczuk R.

Central European Journal of Energetic Materials

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2015

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Vol. 12, no. 2

261--270

EN

Four new nitration methods for the synthesis of 4,4’,5,5’-tetranitro-2,2’- bi-1H-imidazole (TNBI) were examined. TNBI was synthesized by nitration of 2,2’-bi-imidazole (BI) with the following mixtures: (CH3CO)2O/HNO3, (CF3CO)2O/ HNO3, P4O10/HNO3 and H3PO4/P4O10/HNO3. Nitration of BI with a mixture of nitric acid and acetic anhydride leads to 4,4’-dinitro-bi-imidazole. The other nitrating conditions investigated gave TNBI in lower yields (6.0-22.4%). Crystallization of crude TNBI from wet ethanol/acetone gave TNBI as its dihydrate. The structures of BI and TNBI were characterized by 1H, 13C and 15N NMR spectroscopy and elemental analysis. Friction and impact sensitivity, detonability and detonation velocity were determined for pure TNBI dihydrate.

7

Otrzymywanie i badanie właściwości 4,4',5,5'-tetranitro-2,2'-bi-1H-imidazolu (TNBI)

Szala M., Lewczuk R.

Biuletyn Wojskowej Akademii Technicznej

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2013

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Vol. 62, nr 1

34-43

PL

Wykonano przegląd metod nitrowania 2,2'-biimidazolu od jego odkrycia do roku 2012. Zaproponowano dwie nowe ścieżki nitrowania 2,2'-biimidazolu do 4,4',5,5'-tetranitro-2,2'-bi-1H-imidazolu (TNBI). Strukturę produktu pośredniego i TNBI określono na podstawie wyników badań spektroskopowych (¹H, ¹³C NMR, IR). Stwierdzono, że TNBI tworzy stabilny hydrat, który ulega odwodnieniu w temperaturze ok. 80°C. Na podstawie wyników badania DTA /TG określono, że TNBI zachowuje stabilność do temperatury 277°C po czym bez topnienia ulega egzotermicznemu rozkładowi. Zmierzona prędkość detonacji TNBI wynosi 7950 m/s przy gęstości 1,72 g/cm³.

EN

The known synthesis methods of 4,4',5,5'-tetranitro-2,2'-bi-1H-imidazole (TNBI) are reviewed. Two novel nitration methods of 2,2'-biimidazole to TNBI were presented. Solid products of reactions were analyzed using ¹H, ¹³C NMR and IR spectroscopy. Thermal stability has been studied by DTA. Friction sensitivity of main product was examined. Heat of combustion was measured and standard enthalpy of formation was calculated. Detonation velocity of TNBI for the density of 1.72 g/cm³ was measured.

8

Mikroreaktor krzemowo-szklany do syntezy 2-izopropoksy-5- nitrobenzaldehydu

Knapkiewicz P., Skowerski K., Jaskólska D. E. D. E., Kowalski P., Olszewski T.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 10b

98-100

PL

W niniejszym artykule przedstawiono mikroreaktor krzemowo-szklany oraz jego zastosowanie w reakcji selektywnego nitrowania 2- izopropoksy benzaldehydu do 2-izopropoksy-5-nitrobenzaldehydu, ważnego elementu budulcowego nitrowego katalizatora metatezy olefin typu Hoveydy-Grubbsa. Mikroreaktor wykonano technikami mikroinżynieryjnymi z krzemu i szkła, materiałów odpornych na środowisko nitrowania. Dodatkowo mikroreaktor wyposażono w miniaturowe czujniki temperatury oraz zaplanowano wykorzystanie miniaturowych, odpornych na korozję czujników ciśnienia.

EN

Herein we describe a flow-through silicon-glass microreactor and its application in selective nitration of 2-isopropoxybenzaldehyde to 2- isopropoxy-5-nitrobenzaldehyde, important building block of nitro-substituted metathesis catalyst of type Hoveyda-Grubbs. The flow-through microreactor was fabricated using microengineering techniques from silicon and glass, materials resistant to nitration environment. Microreactor is equipped with miniature temperature sensors and with resistant to corrosion pressure sensors.

9

Hazard of Runaway of Nitration Processes in Nitrocompounds Production

Kozak G. D., Raikova V. M.

Central European Journal of Energetic Materials

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2010

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Vol. 7, nr 1

21-32

EN

Hazard of runaway of nitration processes in nitrocompounds production was investigated. Temperature rise in DNT nitration mixes under near adiabatic conditions was measured, and derivative dT/dζ was computed. Heat evolution rate caused by nitration (primary reaction) and oxidation (secondary reaction) were examined by means of elaborated mathematical model. Limiting values of T and dT/dζ for safe process were determined. The second part of investigation concerns detonability of solutions of nitrocompound in sulfuric acid. The detonation failure diameter df and detonation velocity D of solutions of trinitrotoluene, dinitrotoluene, and trinitrobenzene in sulfuric acid and oleum have been measured in the wide range of concentrations at T = 90C. It was shown that the detonability of the nitrocompounds depends signifcantly on the sulfuric acid content. The minimum value of df for the mixture TNT/oleum is about 2 mm, i.e., 30 times less, than that for melted TNT, and practically equals to df of nitroglycerine.

10

Synteza 1-R-nitroetenów

Jasiński R., Mikulska M., Barański A.

Chemik

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2009

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Vol. 62, nr 4

154-164

PL

W artykule usystematyzowano stan wiedzy na temat metod syntezy 1-R-1-nitroetenów. Syntezy te można podzielić na trzy grupy związane z: utworzeniem wiązania podwójnego w nitrozwiązkach nasyconych, wprowadzeniem grupy nitrowej do związku zawierającego podwójne wiązanie pomiędzy atomami węgla oraz modyfikacją struktury cząsteczek posiadających układ nitrowinylowy.

EN

In the presented work was systemized state of knowledge about the synthesis method of 1-R-1-nitroethenes. These syntheses can be divided into three groups: creation of double bond in the saturated nitro compounds, introduction of nitro group into compounds including double bond between carbon atoms as well as modification of molecule structure hawing nitrovinylic system.

11

Study on the Synthesis, Reduction and Reductive Amination of Nitroindan-1-ones. Preparation of N-beta-Hydroxyethyl Derivatives of 6-Aminoindan-1-one and Indan-1,6-diamine

Wodnicka A., Kwiecień H.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 11

2133-2140

EN

Synthesis of 6-aminoindan-1-one and 7-amino-5,6-dimethoxyindan-1-one by nitration of corresponding indanones, followed by selective palladium catalyzed reduction under mild conditions has been described. Reactions of the amines with oxirane leading to N,N-bis-(beta-hydroxyethyl) derivatives were performed. The study of reductive amination of 6-nitroindan-1-one and 5,6-dimethoxy-7-nitroindan-1-one via azines to the corresponding amines as well as synthesis of N,N-bis-(beta-hydroxyethyl) derivatives of the amines was also described.

12

A Study of the Synthesis and Amination of 2,6-Dialkoxy-3,5-dinitropyrazines

Bellamy A. J., Golding P.

Central European Journal of Energetic Materials

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2008

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Vol. 5, nr 2

3-19

EN

A series of 2,6-dialkoxy-3,5-dinitropyrazines (R = Me, Et, Pr) has been synthesized and subjected to amination. The yield and purity of the generated 2,6-diamino-3 ,5-dinitropyrazine was found to be independent of the alkoxy group present in the precursor. This contrasts with the behaviour of 1,3,5-trialkoxy-2,4,6-trinitrobenzene (R = Me, Et, Pr), where the purity of the 1,3,5-triamino- 2,4,6-trinitrobenzene (TATB) produced by amination was very dependent upon the alkoxy group.

13

The Study of Some Potential New Synthetic Routes to LLM-105 (2,6-Diamino-3,5-dinitropyrazine 1-oxide)

Bellamy A. J., Golding P.

Central European Journal of Energetic Materials

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2007

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Vol. 4, nr 3

33-57

EN

The synthesis of LLM-105 (2,6-diamino-3,5-dinitropyrazine 1-oxide) via the direct nitration of 2,6-diaminopyrazine 1-oxide is reported. Two synthetic routes to the starting material 2,6-diaminopyrazine 1-oxide have been investigated. The synthesis of 2,6-diamino-3,5-dinitropyrazine by nitration of 2,6-diaminopyrazine and 2,6-diacetamidopyrazine has also been studied. Whilst mono-nitration of 2,6-diaminopyrazine is very selective, further nitration leads to mixtures of 2,6-diamino-3,5-dinitropyrazine, 6-amino-2-keto-3,5-dinitropyrazine and tetraketopiperazine, the latter predominating in many cases. It was shown that tetraketopiperazine is formed by further reaction of the initially formed 2,6-diamino-3,5-dinitropyrazine. Nitration of 2,6-diacetamidopyrazine does furnish 2,6-diamino-3,5-dinitropyrazine, but the yield is poor.

14

Preparation of Low-melting Compositions Based on 1,3,3-Trinitroazetidine

Katorov D. V., Rudakov G. F., Ladonin A. V., Zhilin V. F., Veselova E. V., Vyalova N. A.

Central European Journal of Energetic Materials

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2007

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Vol. 4, nr 1-2

125-133

EN

Investigations of TNAZ/AzDNAZ mixtures with different TNAZ contents revealed an eutectic composition TNAZ/35/65 with melting point of 61 C. Combined introduction of nitro- and azido groups followed by nitration of tBuDNAZ/tBuAzNAZ mixtures in N2O5/CH3CN and NH4NO3/(CH3CO)2O systems has been investigated. Possibility of synthesis TNAZ/AzDNAZ mixtures of various contents has been shown.

15

Nitration of Toluene and Chlorobenzene with HNO3/Ac2O Catalyzed by Caprolactam-based Bronsted Acidic Ionic Liquids

Ql X., Cheng G., Lu Ch., Qian D.

Central European Journal of Energetic Materials

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2007

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Vol. 4, nr 3

105-113

EN

Several new caprolactam-based Bronsted acidic ionic liquids [Caprolactam]X (X- = pTSO-, BSO-, BF4-, NO3-) with relatively lower cost and lower toxicity were synthesized and for the first time used in catalyzing organic reaction. They showed good catalytic activity in the nitration of toluene and chlorobenzene with HNO3/Ac2O under mild conditions. Among them, [Caprolactam]pTSO was the best one probably because of its better affinity to aromatics than the others. [Caprolactam]pTSO catalyzed the nitration of toluene with achieving a high yield (99.7%, calculated by quantitative GC) and better para-selectivity (ortho/para=1.03) than the traditional mixed acid methodology. And the catalyst can be recycled for four times.

16

Structure Determination of Some Nitro-5,10,15,20-tetrakis(3-methoxyphenyl)porphyrins Using Simple NMR Techniques

Ostrowski S., Łopuszyńska B., Mikus A.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 7

1209-1215

EN

The structures of some nitrosubstituted meso-tetraarylporphyrins were determined by a simple comparison of their 1H NMRspectra, and confirmed by NOE experiments. On the basis of these investigations it was found that in the meso-tetraphenylporphyrin (meso-TPP) and its 3-methoxy, 3-methyl, and 3-chloro-substituted derivatives (in the meso-aryl rings), the electrophilic nitration occurred in position 4-.

17

Filtracja zawiesiny ponitracyjnej

Budzyński P., Dziubiński M.

Inżynieria i Aparatura Chemiczna

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2003

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Nr 1

8-9

EN

Filtration of a nitration suspension, extremely dangerous because of its explosiveness and chemical aggressiveness, was studied. The parameters of filter cloths necessary to accomplish such a filtration, constants of the filtration carried out at constant pressure, and compressibility factor of the precipitata were determined. They enable designing of filtration parameters in an industrial scale. -

18

Intensification of Mass Exchange in Physico-Chemical Processing of Fibrous Materials in a Liquid Medium

Kucharski A., Świątek J., Wrocławski Z.

Fibres & Textiles in Eastern Europe

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2003

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Vol. 11, no. 3 (42)

15--20

EN

Physico-chemical processing is very often used in the textile and paper industries, and in the industry of high-energy materials based on nitrocellulose. Mass exchange in these processes depends on the specific features of the form and structure of the parent substance (reactant). Notwithstanding the differences among the reagents used in the above-mentioned industries, the mass exchanging processes are similar. As liquids acting therein, we have dyes and bleaching agents used as solutions in chemical processing of fibres, acids and inorganic alkali in paper manufacturing, and nitric acid with compounds which form hydrates in the nitration process of cellulose. In general, in all these processes the motion of mass takes place together with chemical reactions of an additive or exchange character. The problems of mass exchange are analysed in this article from the point of view of the designers and constructors of machines and apparatuses which must perform the processes mentioned above. This analysis is based on the characteristic criteria of similarity between quantities, considering the geometric, energetic, and dynamic conditions which determine the process intensity. It has been proved that, according to the present state of knowledge and technique, the laminar liquid wall-surface layer which surrounds the fibrous parent substance acts as the main resistance for mass motion. It is possible to decrease this layer by several times (even over 30 times), and by this means significantly intensify the process. A process intensification criterion is presented.

PL

Obróbka fizyko-chemiczna materiałów włóknistych jest dość powszechna w przemyśle włókienniczym, papierniczym i materiałów wysokoenergetycznych, opartych na nitrocelulozie. Wymiana masy w tych procesach jest uwarunkowana szczególnymi cechami postaci substratu. Mimo różnicy reagentów procesy są podobne: w chemicznej obróbce włókna - barwniki i środki wybielające w roztworach; w produkcji papieru - kwasy i ługi nieorganiczne; w procesie nitracji celulozy - kwas azotowy ze związkami tworzącymi hydraty. Ruch masy w omawianych procesach odbywa się z reguły z równoczesną reakcją chemiczną (addytywną lub wymienną). Zagadnienie poddano analizie ze stanowiska projektantów i konstruktorów maszyn i aparatów wykonujących proces, opierając się na związkach liczb znamiennych, biorąc pod uwagę warunki natury geometrycznej, energetycznej i dynamicznej, które determinują intensywność procesu. Wykazano, że przy obecnym stanie wiedzy i techniki o procesie wymiany masy, główny opór dla ruchu masy stanowi laminarna warstwa przyścienna płynu, otaczająca substrat włóknisty. Odpowiednim rozwiązaniem konstrukcyjnym można tę warstwę przyścienną wielokrotnie (ponad 30-krotnie) zmniejszyć i ewidentnie zintensyfikować proces. Podano kryterium intensyfikacji procesu.

19

Nitrowanie toluenu 65-proc. kwasem azotowym w obecności katalizatora MoO3/SiO2

Skupiński W., Malesa M.

Przemysł Chemiczny

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2002

|

T. 81, nr 8

519-521

20

Nitrated coals as active carbon precursors.

Tamarkina Y.V., Shendrik T.G.

Prace Naukowe Instytutu Chemii i Technologii Nafty i Węgla Politechniki Wrocławskiej. Konferencje

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2002

|

Vol. 10, nr 57

75-80

EN

It has been studied the interaction of coals ranging from brown coal (Cdaf=70.4%) to anthracite (Cdaf=95.2%), with equimolar nitrating system HNO3-Ac2O (20-2C) yielding nitrated coals named as structurally modified coals (SMCs). In comparison with the parent coals, SMCs have more disordered structures contain aromatic NO2 groups and different oxygen functionalities as substitutes. Besides, SMCs are more thermolabile comparing with parent coals. Nitrated coals are better precursors of active carbons and may be activated by KOH into adsorbents with surface area as high as 1200 in 2/g.