Mixture Of Ammonium Nitrate Research Articles

Hygroscopic Behavior of Ammonium Sulfate, Ammonium Nitrate, and their Mixture Particles

Inorganic species such as ammonium sulfate (AS) and ammonium nitrate (AN), which significantly affect air quality, visibility degradation, and climate change, occupy 20–50% among ambient fine aerosol mass. In the present study, laboratory generated, micrometer sized, pure AS, AN, and AS-AN mixture aerosol particles at 9 mixing ratios (mole fraction of AS, XAS =0.02, 0.035, 0.1, 0.15, 0.2, 0.28, 0.5, 0.6, and 0.8) were examined systematically to observe their hygroscopic behavior, to derive experimental phase diagrams for efflorescence and deliquescence, and to obtain chemical micro-structures using in-situ Raman microspectrometry (RMS). All the nebulized AS-AN mixture particles experienced only one-stage efflorescence at 15–40% relative humidity (RH) during dehydration process, revealing that all the compounds in the particles crystallized nearly simultaneously. Nebulized AS-AN mixture particles of eutonic composition (XAS =0.035) showed singlestage transition at a mutual deliquescence relative humidity (MDRH) of 63.6%, whereas the others exhibited two-stage deliquescence transitions during humidification process, i.e., the eutonic component dissolved at MDRH, and the remainder in the solid phase dissolved completely at their DRHs, resulting in a phase diagram composed of four different phases, as predicted thermodynamically. The measured MDRH and second DRHs of mixture particles with mixing ratios of 0.035<XAS<0.33 are either higher or lower than the theoretical values, while only the experimental second DRHs of mixture particles with mixing ratios of XAS>0.33 are higher than the theoretical values calculated from E-AIM model, which might be due to the variations of crystal formation when the efflorescence occurred. As reported previously, AS and AN mixture droplets can crystallize as the mixture of pure crystal and stable and/or metastable double salts (2AN·AS and/or 3AN·AS, respectively) and the degree of metastability might differ under different conditions. Our results also indicate that the AS-AN mixture particles can crystallize into different forms, leading to diverse MDRHs and DRHs than the theoretical ones, which can promote their capability of probable heterogeneous chemistry on the aqueous aerosol surface.

The diameter effect in Bullseye powder

Detonation velocity as a function of charge diameter is reported for Alliant Bullseye powder. Results are compared to those of mixtures of ammonium nitrate mixed with aluminum and ammonium nitrate mixed with fuel oil. Additionally, measurements of free surface velocity of flyers in contact with detonating Bullseye are presented and results are compared to those of hydrocode calculations using a Jones–Wilkins–Lee equation of state generated in a thermochemical code. Comparison to the experimental results shows that both the free surface and terminal velocities were under-predicted.

Application of Neutron-Gamma Analysis for Determining Compost C/N Ratio

The possible application of Pulsed Fast/Thermal Neutron Analysis (PFTNA) for determining the carbon-to-nitrogen ratio (C/N) of compost will be discussed. This analysis method has several advantages over traditional chemical analysis, including that it is a nondestructive in situ method that does not require extensive sample collection and it analyzes much larger volumes of material (∼1 m3) than traditional chemical analysis (∼1 cm3). The amount of carbon can be determined by irradiating compost with neutrons and measuring the gamma ray peak at an energy of 4.44 MeV that appears due to inelastic scattering. Nitrogen can be determined by measuring the gamma ray peak at 10.83 MeV that appears due to thermal neutron capture. For C/N measurements, a calibration line that relates the C/N mass ratio to the carbon/nitrogen gamma peak ratio should first be constructed; our calibration line was constructed using carbon–ammonium nitrate mixtures. PFTNA measurements were then used to determine carbon and nitrogen peak values in order to utilize the calibration line for calculating the C/N mass ratio. The workability of this methodology has been demonstrated in laboratory experiments. The applicability of PFTNA for compost C/N ratio determinations was evaluated with Monte Carlo computer simulations of neutron propagation in large compost volumes (Geant4 toolkit) and experimental measurements of real compost (volume 1.3 m3). Data from computer simulations and experiments demonstrated that the PFTNA method is fully applicable for determining the C/N ratio in compost material up to values of 25 and even greater.

Ammonium nitrate enriched with sulfur influences wheat yield and soil properties

The effect of fertilization with a new fertilizer on Polish market, a mixture of ammonium nitrate and ammonium sulfate (30% N, 6% S), was analysed in a three-year field experiment. The mixture commonly available on the market (26% N, 13% S) and ammonium nitrate, were used for comparison. Each fertilizer was applied in three doses: 150, 200 and 250 kg N/ha/year (simultaneously, 30, 40 and 50 kg S/ha were introduced with the mixtures). The highest mean (of the three years) grain yield (8.27 t/ha) was obtained after application of 200 kg N and 40 kg S/ha as the new fertilizer, with almost no significant effect of the type and dose of sulfur-containing fertilizers. Sulfur content in the grain was highest after the new fertilizer application; the content increased with increasing fertilizer dose. The highest mean protein (13.9–14.3%) and gluten (28.3–28.9%) content were recorded after application of 250 kg N/ha, and Zeleny sedimentation index (45.0–45.3 cm&lt;sup&gt;3&lt;/sup&gt;) – after application of 250 kg N and 50 kg S/ha, regardless of the fertilizer. Sulfur intensified the acidifying effect of ammonium nitrate and increased the content of sulfates in the soil.

Mineral fertilizers with iron influence spring rape, maize and soil properties

ABSTRACTBecause of low content of available iron (Fe) in soils and its poor mobility in plants, iron fertilization is necessary. Different forms of iron (mineral salts, chelates, nanomaterials) and fertilization strategies (soil and foliar application of solid or liquid fertilizers) are used. The effect of solid mineral fertilizers (A: a mixture of ammonium nitrate and dolomite; B: a mixture of ammonium nitrate and sulfate) enriched with iron sulfate was assessed during a three-year pot experiment. Iron addition did not change the yield of spring rape (first year) or maize (second and third year) significantly, and the effect on iron content in the plants was ambiguous. Fertilizer B with iron had the greatest yield-forming effect, increasing the yield of aboveground parts by 355–874%, and of roots by 211–692% in particular years. All fertilizers (especially containing sulfur) acidified the soil. After the experiment, pH of the soil fertilized with sulfur was 4.1, and of the unfertilized soil – 5.2. Iron addition increased the content of mobile and exchangeable iron in the soil by 12–110% and 2–58%, respectively, but not the content of the fraction bound to MnOx. Combination of sulfur and iron fertilization has a potential to improve soil abundance and plant yield.

Estimating Chemical Conversion Rates for Composite Explosives on the Basis of Experimental Data on Pseudo-Ideal Detonation

The conditions for the appearance of a plateau-like region called pseudo-ideal detonation in the dependence of the velocity of detonation (VOD) of composite explosives on the diameter of a charge were considered. A theoretical model of steady-state non-ideal detonation with a slightly curved front and a two-stage mechanism of chemical reaction was used for analysis. The calculations were performed for a trinitrotoluene-50% ammonium nitrate mixture and a mechanically activated ammonium perchlorate-20% aluminum mixture. The coefficients of the equations describing the global chemical conversion rates of components were fitted in the calculations. In both cases, the dependence of the VOD on the diameter of the reciprocal charge with a plateau-like region was obtained for an increasing conversion rate of the major explosive (trinitrotoluene and ammonium perchlorate, respectively).

Mechanical and Thermal Sensitivity of Mixtures of Ammonium Nitrate with Combustible Hydrocarbons

Two explosive compositions ISU-4K and ISU-5R based on ammonium nitrate with added coke, diesel fuel, and rubber crumbs are tested so as to establish their sensitivity to mechanical and thermal perturbations. The flash point corresponding to 60-s delay is established. The kinetic parameters of thermal disintegration of the explosives are determined. The information obtained may be used in compiling standard documents (of GOST, OST, TU, VTU, and other types) and writing industrial regulations.

Inhibition effect of ammonium dihydrogen phosphate on the thermal decomposition characteristics and thermal sensitivity of ammonium nitrate

In order to analyze the inhibition effect of the additive on the thermal decomposition characteristics of ammonium nitrate (AN), thermal stability and thermal decomposition behavior of AN and its mixtures with various concentrations of ammonium dihydrogen phosphate (ADP) are systematically investigated by DSC-TG, DSC-TG-QMS and TG-FTIR. Breaking point value of the samples is obtained as an evaluation parameter for thermal safety. Experimental results show that the AN-ADP mixtures show higher onset decomposition temperatures, narrower reaction temperature region and lower enthalpy values than those of pure AN. The main evolved decomposition gases of AN are NH3, H2O, NO, N2O, NO2 and HNO3, while the major gaseous products of the AN mixture with ADP are NH3, H2O, NO, N2O and NO2. Furthermore, the generation of NO and NO2 is obviously postponed in the AN mixture. In addition, the breaking point value of AN is markedly improved by ADP. The decomposition mechanism of AN-ADP mixture is concluded and the inhibition mechanism of ADP is proposed. It is concluded that ADP is an effective inhibitor for AN and its thermal stability is effectively enhanced.

Modelling and Testing of Blast Effect On the Structures

As a blasting agent in the blasting and mining engineering, has been using one of so called new generation of explosives which offer greater flexibility in their range and application, and such explosive is ANFO. It is type of explosive consists of an oxidiser and a fuel (ammonium nitrate and fuel oil). One of such ANFO explosives which are industrially made in Slovakia is POLONIT. The explosive is a mixture of ammonium nitrate, methyl esters of higher fatty acids, vegetable oil and red dye. The paper deals with the analysis of structure subjected to the blast load created by the explosion of POLONIT charge. First part of paper is describing behaviour and characteristic of blast wave generated from the blast (detonation characteristics, physical characteristics, time-history diagram etc.) and the second part presents the behaviour of such loaded structures, because of the analysis of such dynamical loaded structure is required knowing the parameters of blast wave, its effect on structure and the tools for the solution of dynamic analysis. The real field tests of three different weight of charges and two different structures were done. The explosive POLONIT was used together with 25 g of ignition explosive PLNp10. Analytical and numerical model of blast loaded structure is compared with the results obtained from the field tests (is compared with the corresponding experimental accelerations). For the modelling structures were approximated as a one-degree system of freedom (SDOF), where the blast wave was estimated with linear decay and exponential decay using positive and negative phase of blast wave. Numerical solution of the steel beam dynamic response was performed via FEM (Finite Element Method) using standard software Visual FEA.

Convective burning of fine ammonium nitrate–aluminum mixtures in a closed volume bomb

It is commonly assumed that the burning of ammonium nitrate–aluminum mixtures is much less prone to undergo a transition to explosion and detonation than similar mixtures based on ammonium perchlorate. However, this conclusion has been made for mixtures based on commercial-grade ammonium nitrate with large particles. In this study, the combustion of fine loose-packed mixtures of ammonium nitrate and aluminum in a closed-volume bomb has been examined. It has been shown that fine mixtures (ammonium nitrate with a particle size of less than 40 µm and an ASD-4 aluminum powder with spherical particles with a size of about 4 µm) undergo high-intensity combustion; in experiments with a stoichiometric mixture, explosions are observed. The explosions occur in the initial phase of convective combustion and lead to abrupt pressure pulsations with an amplitude of a few kilobars and to the destruction of the cup in which the sample is placed. The dynamics of development of the explosion has been analyzed in detail using numerical simulation. According to the results of experiments with varied parameters—the degree of dispersion of the ammonium nitrate powders, the aluminum content in the mixture, the length and diameter of the charge, and the level of pressure generated by the combustion of the igniter,—threshold conditions have been determined to separate the following modes: the absence of ignition, layer-by-layer combustion, or convective combustion with a transition into an explosion in experiments with a stoichiometric mixture.

Cohesive Hamaker Constants and Dispersive Surface Energies of RDX, PETN, TNT, and Ammonium Nitrate‐Based Explosives

AbstractInverse gas chromatography (IGC) was used to characterize dispersive surface energies γSDand cohesive Hamaker constantsAiifor RDX, PETN, TNT, ammonium nitrate (AN), and AN‐based explosives at 303 K. The γSDfor RDX at 303 K is compared to previous studies and generally found to be in good agreement, substantiating the use of NESTT training materials to characterize explosives via IGC. Additionally, the effect of the amount of fuel in the AN mixtures on γSDis examined using simple linear regression. Finally, the IGC‐predictedAiivalues are compared to Lifshitz estimations forAiiof RDX, PETN, TNT, and AN.

Seed/Catalyst-Free Growth of Gallium-Based Compound Materials on Graphene on Insulator by Electrochemical Deposition at Room Temperature.

We report the growth of gallium-based compounds, i.e., gallium oxynitride (GaON) and gallium oxide (Ga2O3) on multilayer graphene (MLG) on insulator using a mixture of ammonium nitrate (NH4NO3) and gallium nitrate (Ga(NO3)3) by electrochemical deposition (ECD) method at room temperature (RT) for the first time. The controlling parameters of current density and electrolyte molarity were found to greatly influence the properties of the grown structures. The thicknesses of the deposited structures increase with the current density since it increases the chemical reaction rates. The layers grown at low molarities of both solutions basically show grain-like layer with cracking structures and dominated by both Ga2O3 and GaON. Such cracking structures seem to diminish with the increases of molarities of one of the solutions. It is speculated that the increase of current density and ions in the solutions helps to promote the growth at the area with uneven thicknesses of graphene. When the molarity of Ga(NO3)3 is increased while keeping the molarity of NH4NO3 at the lowest value of 2.5 M, the grown structures are basically dominated by the Ga2O3 structure. On the other hand, when the molarity of NH4NO3 is increased while keeping the molarity of Ga(NO3)3 at the lowest value of 0.8 M, the GaON structure seems to dominate where their cubic and hexagonal arrangements are coexisting. It was found that when the molarities of Ga(NO3)3 are at the high level of 7.5 M, the grown structures tend to be dominated by Ga2O3 even though the molarity of NH4NO3 is made equal or higher than the molarity of Ga(NO3)3. When the grown structure is dominated by the Ga2O3 structure, the deposition process became slow or unstable, resulting to the formation of thin layer. When the molarity of Ga(NO3)3 is increased to 15 M, the nanocluster-like structures were formed instead of continuous thin film structure. This study seems to successfully provide the conditions in growing either GaON-dominated or Ga2O3-dominated structure by a simple and low-cost ECD. The next possible routes to convert the grown GaON-dominated structure to either single-crystalline GaN or Ga2O3 as well as Ga2O3-dominated structure to single-crystalline Ga2O3 structure have been discussed.

Study of non-conventional fuels for explosives mixes

The use of ammonium nitrate and fuel oil (ANFO) results in low cost blasting. Such costs may be further reduced by replacing fuel oil with alternative fuels such as biomass (biodiesel, rice straw, corn cob, sugar cane bagasse) and tires residue. This paper investigates the use of other fuels instead of fuel oil by measuring the detonation velocity (VOD) and verifying the importance of these fuels in an explosive mixture. Except for biodiesel, all the tests conducted for the mixture of ammonium nitrate and alternative fuels showed poor performance when compared with ANFO. The achieved percentage of detonation velocity (VOD) of the mixtures in relation to the ANFO were 55.4% for ammonium nitrate + rice straw, 64.9% for ammonium nitrate + corn cob, 70.1% for ammonium nitrate + sugar cane bagasse, 74.4% for ammonium nitrate + tires residue and 93.7% for ammonium nitrate + biodiesel. This study indicates that the methodology proposed can be applied as a reference for determination and preparation of explosive mixtures of fuel and oxidizing agents since in all the tests conducted the detonation of the charges occurred.

Reactive atomistic simulations of shock-induced initiation processes in mixtures of ammonium nitrate and fuel oil

Ammonium nitrate mixed with fuel oil (ANFO) is a commonly used blasting agent. In this paper we investigated the shock properties of pure ammonium nitrate (AN) and two different mixtures of ammonium nitrate and n-dodecane by characterizing their Hugoniot states. We simulated shock compression of pure AN and ANFO mixtures using the Multi-scale Shock Technique, and observed differences in chemical reaction. We also performed a large-scale explicit sub-threshold shock of AN crystal with a 10 nm void filled with 4.4 wt% of n-dodecane. We observed the formation of hotspots and enhanced reactivity at the interface region between AN and n-dodecane molecules.

Phase diagram of ammonium nitrate

Ammonium Nitrate (AN) has often subjected to uses in improvised explosive devices, due to its wide availability as a fertilizer and its capability of becoming explosive with slight additions of organic and inorganic compounds. Yet, the origin of enhanced energetic properties of impure AN (or AN mixtures) is neither chemically unique nor well understood -resulting in rather catastrophic disasters in the past1 and thereby a significant burden on safety in using ammonium nitrates even today. To remedy this situation, we have carried out an extensive study to investigate the phase stability of AN at high pressure and temperature, using diamond anvil cells and micro-Raman spectroscopy. The present results confirm the recently proposed phase IV-to-IV' transition above 17 GPa2 and provide new constraints for the melting and phase diagram of AN to 40 GPa and 400 °C.

Combustion of carbonized coal residue in a mixture of ammonium nitrate and supercritical water

The possibility of low-temperature oxidation of a solid carbonized coal residue in a mixture of NH4NO3 and supercritical water (723 K and 30 MPa) is shown for the first time and its mechanism is described. Conjugate processes of oxidation of the carbonized residue and formation of combustible gases H2 and CH4 caused by the participation of H2O in redox reactions was found. It was established that the ash residue has a high porosity and consists of agglomerated nanoparticles of silicon and metal oxides.

Volumetric properties of ammonium nitrate in N-methylformamide

The volumetric properties (apparent molar volumes and partial molar volumes) of ammonium nitrate in N-methylformamide (NMF) have been evaluated from the density data and discussed in the term of respective ionic and dipole interactions. The densities of the NMF+ammonium nitrate mixtures were measured at T=308.15 to 348.15 K for different ammonium nitrate molalities in the range from 0 to 8.4624 mol·kg−1. The apparent molar expansibility and the coefficients of thermal expansion were also calculated. The results were compared with those obtained for DMF+ammonium nitrate mixtures.

Phase diagram of ammonium nitrate

Ammonium Nitrate (AN) is a fertilizer, yet becomes an explosive upon a small addition of chemical impurities. The origin of enhanced chemical sensitivity in impure AN (or AN mixtures) is not well understood, posing significant safety issues in using AN even today. To remedy the situation, we have carried out an extensive study to investigate the phase stability of AN and its mixtures with hexane (ANFO-AN mixed with fuel oil) and Aluminum (Ammonal) at high pressures and temperatures, using diamond anvil cells (DAC) and micro-Raman spectroscopy. The results indicate that pure AN decomposes to N2, N2O, and H2O at the onset of the melt, whereas the mixtures, ANFO and Ammonal, decompose at substantially lower temperatures. The present results also confirm the recently proposed phase IV-IV' transition above 17 GPa and provide new constraints for the melting and phase diagram of AN to 40 GPa and 400°C.

A Burning Rate Equation as a Function of Pressure and Temperature for a BTA · NH3/PSAN Mixture

The burning rate of propellants is affected by pressure and temperature. The relation between the burning rate and pressure has been well studied. However, the effect of the initial temperature on the burning rate has not been investigated quantitatively. In this study, the burning rate of bis (1H-tetrazolyl) amine ammonium salt and potassium nitrate phase-stabilized ammonium nitrate mixtures was examined and an equation for the burning rate as a function of pressure and temperature was obtained. In general, the burning rates predicted by the regression equations were in good agreement with the observed values. The temperature sensitivities were also predicted using the regression equation and compared with the observed values and good agreement was found between the predicted and observed values.

Equation of Burning Rate as a Function of Pressure and Temperature for 1H-Tetrazole/Ammonium Nitrate Mixtures

In this study, based on the observed burning rate of 1H-tetrazole and ammonium nitrate mixtures at pressures of 1–10 MPa and temperatures of 238–358 K, equations expressing the burning rate as a function of pressure and temperature were derived. In general, the calculated burning rates were in good agreement with the observed values.