The influence of the pressure of gaseous reaction products on the rate of dissociation of basic aluminium ammonium sulfate and general regularities of the process

1985 ◽  
Vol 92 ◽  
pp. 113-115 ◽  
Author(s):  
Barbara Pacewska ◽  
Janusz Pysiak ◽  
Anna Klepańska
2012 ◽  
Vol 1405 ◽  
Author(s):  
Paul Anderson ◽  
Paula Cook ◽  
Wendy Balas-Hummers ◽  
Andy Davis ◽  
Kyle Mychajlonka

ABSTRACTIn development of new explosives, it is often necessary to balance a number of attributes in performance while certain formulation constraints exist. Statistical design of experiments (DOE) is a valuable tool for rapid formulation optimization and minimization of costly and hazardous testing. During the development of metal-loaded explosives designed for enhanced blast, it was discovered that upon proper formulation, aluminum additives obtained full reaction by 7 volume expansions, which resulted in extremely high Gurney energies equivalent to LX-14 and PBXN-5 but with lower loading of nitramines. The early aluminum oxidation can be described by Eigenvalue type detonations, where the fully reacted Hugoniot of the condensed phase aluminum oxide and explosive products lies below the unreacted aluminum Hugoniot. Such an analysis describes fully the agreement of aluminum consumption by 7 volume expansions from 1-inch copper cylinder expansion tests and an analytic cylinder model, as well as detonation calorimetry. With the early reaction of aluminum also comes a shift in the gaseous reaction products to higher enthalpy species such as CO and H2, leading to further augmentation of blast. Thus, both the mechanical energy (for fragmentation or “metal pushing”) and blast (for structural targets) are available in a single explosive fill. This provides capability for combined metal pushing and blast in a single explosive that was not previously possible. Development of such explosives and the importance of modern statistical design of experiments will be shared.


The detonation products of high explosives are dependent on pressure and also on the confinement under which the detonation reaction proceeds. To determine the detonation products of less sensitive high explosives such as trinitrotoluene/ nitroguanidine and polymer bonded explosive charges with polybutadiene binder containing cyclotrimethylene trinitramine, together with or without aluminium, experiments have been performed in a stainless steel chamber of a volume of 1.5 m 3 . These experiments were done under different ambient argon pressures up to 0.3 MPa. Gaseous reaction products were analysed by mass spectrometry and chemiluminescence analysis. Solid reaction products were analysed for measuring the carbon residue or unreacted aluminium. It was found that the detonation products were highly dependent on the ambient pressure of argon. The most important changes of the reaction products and therefore also of the energy output were found between vacuum and atmospheric pressure of argon. With increasing pressure, H 2 and CO decrease and CO 2 , H 2 , C 8 , NH 3 , HCN and CH 4 increase together with the reaction enthalpy. By analysing the physical structure of the carbon residue, diamonds have been observed between 4 and 7 nm in diameter.


The introduction of chlorine atoms into organic compounds causes marked changes in properties which can often be explained in terms of a displacement of electrons under the influence of the substituent. It is an interesting question how far these influences will show themselves in the kinetic behaviour of the substituted molecules. Accordingly the thermal decomposition of chloral and its catalysis by iodine have been studied. The decomposition is a homogeneous gaseous reaction which can be compared with the decomposition of acetaldehyde and propionic aldehyde. Apparatus The apparatus was of the usual type, with a silica reaction vessel heated in an electric furnace. A tube led to a capillary mercury manometer outside the furnace, and the course of the reaction was followed by observing the rate of pressure increase. In view of the relatively high boiling point of chloral it was necessary to keep all the connecting tubes heated to 80°-90° C. Considerable difficulty was experienced with the lubricants for the stop-cocks operating at this temperature. A special high temperature vapourless grease was used, but even this showed a tendency to run and foul the connecting tubes. The reaction products also tended to foul the apparatus so that frequent cleaning of the whole, including the manometer and the mercury pump, was required.


2016 ◽  
Vol 1 ◽  
pp. 07
Author(s):  
O. A. Caceros ◽  
P. González ◽  
I Hidalgo ◽  
B. Moscoso ◽  
W. R. Raun

Soil fertility studies have been conducted on the southern coastal plain of Guatemala for several years without showing significant response to phosphorus and sulfur fertilizer applications. In 1987, various exploratory trials were established to evaluate various methods of application for phosphorus, sulfur and nitrogen. Nitrogen sources evaluated were ammonium sulfate and urea. Beef manure was also evaluated in combination with ammonium sulfate. Various other N (as urea), P, S combinations were Included in this trial using CaSO4 as the S source. Banding phosphorus and nitrogen together especially ammonium sulfate with triple superphosphateprovided excellent response across locations. Due to the pH reduction within the NP band, H2PO4 availability at lower pH is Increased as has been demonstrated by others. Ammonium sulfate was by far a better N source compared to urea when applied alone and as such an S response was considered probable in 2 or the five locations. Gypsum applications were evaluated both as a source of sulfur and as an alternative to improving P availability by applying this source with triple superphosphate in a joint band. It was expected that the reaction products from applying gypsum and P together increase the P availability since the precipitated products (hypothesized, dicalcium phosphate dihydrate and dicalcium phosphate) would not be fixed and as such slowly available at low pH. Also If by combining triple superphosphate and gypsum in a joint hand, precipitation products DCIP and DCPD would reduce the amount of fertilizer P complexed with Fe and Al hydroxides and or allophane. Antagonistic Interactions were found between S and P which suggests that fertilizer P applications could induce S deficiencies (where S was not applied) since P may be replacing SO4 on the exchange complex of soils thought to have high anion exchange capacities and/or significant amounts of adsorbed SO4.


2014 ◽  
Vol 1644 ◽  
Author(s):  
Renate Kellermann ◽  
Dan Taroata ◽  
Martin Schiemann ◽  
Helmut Eckert ◽  
Peter Fischer ◽  
...  

ABSTRACTIn this work, electrochemically recyclable lithium is analyzed as high energy density, large scale storage material for stranded renewable energy in a closed loop. The strongly exothermic reaction of lithium with carbon dioxide (CO2) yields thermal energy directly comparable to the combustion of coal or methane in an oxygen containing atmosphere. The thermal level of the reaction is sufficient for re-electrification in a thermal power plant compatible process.The reaction of single lithium particles, avoiding particle-particle interactions, is compared to the combustion of atomized lithium spray in a CO2 containing atmosphere. Particle temperatures of up to 4000K were found for the reaction of single lithium particles in a CO2, nitrogen (N2), oxygen (O2) and steam gas mixture. Furthermore the combustion of atomized lithium spray in both dry CO2 atmosphere and CO2/steam gas mixture was analyzed. The identified solid reaction products are lithium carbonate, lithium oxide and lithium hydroxide. The formation of carbon monoxide (CO) as gaseous reaction product is demonstrated. Carbon monoxide is a valuable by-product, which could be converted to methanol or gasoline using hydrogen.


Author(s):  
Alexei Miassoedov ◽  
Christoph Homann ◽  
Leo Sepold ◽  
Martin Steinbru¨ck

QUENCH is a series of experiments being performed at the Forschungszentrum Karlsruhe, to investigate quenching with water and cooling with steam of oxidized and partially degraded fuel rod bundle. Test QUENCH-07 was performed to address the effects of chemical behavior and degradation of B4C absorber rods, especially the oxidation of B4C, its interaction with stainless steel, formation and composition of gaseous reaction products and the impact of absorber rod degradation on surrounding rods. An unexpected feature of the experiment was the strong oxidation during the cooldown phase accompanied by an increased release of all gaseous species. Temperature escalation and hydrogen release during cooldown were observed for the first time in any steam cooled QUENCH experiment. Since not only the absorber rod was a novel feature but also the steam flow rate during cooldown was smaller in comparison with previous tests, it is not yet clear whether this escalation can be attributed to the effect of B4C.


1962 ◽  
Vol 35 (1) ◽  
pp. 118-132 ◽  
Author(s):  
G. G. Wanless ◽  
Peter E. Wei ◽  
John Rehner

Abstract The role which sulfur plays in the peroxide vulcanization of polyisoparaffins has been investigated. The problem was studied by using a system in which 2,4dimethylpentane is a model for the polyisoparaffin chain. Two alternative reaction mechanisms are proposed. Work with the model system shows that polysulfides formed from the isoparaffin are the dominant products. By analogy it is inferred that polysulfide linkages join the polyisoparaffin chains, preferably at what were formerly tertiary hydrogen sites. Nearly all of the high boiling products are disulfides and, or, polysulfides, and these total at least a 28 mole per cent yield based on peroxide charged. Thus, it is indicated that sulfur plays a major role, and does not simply prevent minor side reactions. Study of the gaseous reaction products indicates that sulfur does not alter the course of the initiation step. A reaction mechanism is proposed which is consistent with literature and with our experimental work.


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