Showing papers on "Potassium nitrate published in 2001"

Gas generating compositions

Abstract: A low-solids gas generating composition, which is a mixture of a fuel selected for the group consisting of cellulose, cellulose acetate, hexamine, and mixtures thereof, and an oxidizer selected from the group consisting of ceric ammonium nitrate, lithium nitrate, lithium perchlorate, sodium perchlorate, phase stabilized ammonium nitrate, a combination of ammonium nitrate with potassium nitrate, potassium perchlorate, or mixtures thereof, such that the combination is a solid solution, a mixture of ammonium perchlorate and at least one alkali metal salt, and mixtures thereof. The combination of ammonium nitrate with other salts in solid solution is intended to phase stabilize the ammonium nitrate. The oxidizer-fuel mixture is within about 4 percent of stoichiometric balance. Useful alkali metal salts include lithium carbonate, lithium nitrate, sodium nitrate, potassium nitrate, and mixtures thereof. The preferred oxidizers for the gas generating composition of the invention are ceric ammonium nitrate, lithium nitrate, lithium perchlorate, sodium perchlorate, a mixture of ammonium perchlorate and at least one alkali metal salt, and mixtures thereof. In addition, the gas generating composition may include an energizing agent, such as RDX or HMX. The gas generating composition of the invention may further comprise sub-micron fumed silica to reduce moisture contamination and serve as a processing and powder flow aid and/or a binder, and may be in the form of pressed pellets, grains, or granules.

Dispersion of Potassium Nitrate and the Resulting Strong Basicity on Zirconia

Abstract: A novel solid superbase is derived from zirconia-supported potassium nitrate. Dispersion and decomposition of potassium nitrate on zirconia were investigated and compared with that on alumina to explore the effect of the support on the preparation of solid strong bases. Spontaneous dispersion capacity of KNO3 on ZrO2 was found to be 8.1 K+ nm-2, very close to that of a vacant site on ZrO2. An unusually strong basicity was generated on ZrO2 through decomposition of the loaded KNO3 that began around 613 K, enhancing the catalytic activity of ZrO2 in cis-but-2-ene isomerization at 273 K. Moreover, KNO3/ZrO2 samples, except 34% KNO3/ZrO2, possessed a base strength of H- = 27.0 that was characteristic of solid superbases.

Effect of potassium nitrate and fluoride on carbamide peroxide bleaching.

Abstract: Objectives The purpose of this study was to assess the effect on tooth sensitivity when potassium nitrate and fluoride were added to a 10% carbamide peroxide bleaching gel. Method and materials Seventeen maxillary and four mandibular arches were bleached using the at-home bleaching technique. The bleaching treatment consisted of the simultaneous use of a 10% carbamide peroxide gel containing 3% potassium nitrate wt/vol and 0.11 fluoride ion wt/vol on one side of the midline and a 10% carbamide peroxide gel only (control) on the other side of the midline for 14 nights. A visual analog scale for each side of the dental arch was used by the patients to assess tooth sensitivity and tooth whitening. Preoperative and postoperative photographs were also taken. Results The addition of potassium nitrate and fluoride significantly decreased the total tooth sensitivity reported by the patients. The addition did not significantly change the whitening efficacy of the carbamide peroxide bleach. Conclusion A 10% carbamide peroxide bleaching gel containing potassium nitrate and fluoride produced less tooth sensitivity than did the control bleaching gel during a 2-week at-home bleaching treatment.

Biodegradation of Diesel Fuel in Soil Under Various Nitrogen Addition Regimes

Abstract: Bioremediation is a growing technology for treating fuel-contaminated soils. Many biological, physical, and chemical parameters control the rate and efficiency of this process, including type and concentration of contaminants, temperature, oxygen content, and nutrient status. This study investigated the effect that nitrogen sources and concentrations had on the degradation rate of diesel fuel in nutrient limited soil at two carbon-to-nitrogen ratios. The different sources of nitrogen studied were ammonium nitrate, ammonium sulfate, potassium nitrate, urea, and urea oligomers (control release fertilizer). Laboratory experiments were conducted on field-contaminated soil using sealed bioreactors at a controlled temperature of 25°C. For both carbon-to-nitrogen ratios tested, hydrocarbon degradation rates were the highest for the ammonium sulfate (20:1 at 0.032 d−1; 40:1 at 0.019d−1) and urea treatments (20:1 at 0.025 d−1; 40:1 at0.011 d−1). A degradation rate correlation as a function of nitrate and ammonia c...

Relation of sand content, pH, and potassium and phosphorus nutrition to the development of sudden death syndrome in soybean

Abstract: Development of sudden death syndrome (SDS) of soybean (Glycine max L. Merr.), caused by Fusarium solani (Mart.) Sacc. f. sp. glycines (Fsg), was studied in relation to sand content, pH, and potassium and phosphorus nutrition under controlled environments. Incidence and severity of SDS increased by approximately two- and four-fold, respectively, as the sand content in soil increased from 53 to 100%. Disease severity increased by an average of 21% at soil pH = 7.7 compared to pH = 5.5. Amending the soil with potassium chloride resulted into an average decrease of 36% in SDS severity compared to the control; conversely, disease severity was increased by an average of 21% with calcium phosphate, 32% with potassium phosphate, 43% with potassium sulfate and sodium phosphate, and 45% with potassium nitrate compared to the controls. In vitro conidial germination of Fsg was not significantly affected by potassium and phosphorus amendments. However, mycelial linear growth was enhanced by an average of 15, 22, and 2...

Development of a solution model to correlate solubilities of inorganic compounds in water vapor under high temperatures and pressures

Abstract: A solution model, based on the regular solution theory coupled with Flory-Huggins entropy term, was developed for the calculation of solubilities of inorganic compounds in water vapor under high temperatures and pressures. The solubilities of sodium chloride (NaCl), potassium hydroxide (KOH), sodium sulfate (Na 2 SO 4 ), lead oxide (PbO), silicon oxide (SiO 2 ), lithium nitrate (LiNO 3 ), sodium nitrate (NaNO 3 ) and potassium nitrate (KNO 3 ) were correlated by optimizing internal energies and molar volumes of inorganic compounds which give their solubility parameters.

High Affinity of Thallium Ions to Copper Hexacyanoferrate Films

Abstract: High affinity of thallium(I) ions with respect to a copper hexacyanoferrate (CuHCF) film was found. Interaction between the CuHCF film and thallium(I) ions was investigated using the electrochemical quartz crystal microbalance and cyclic voltammetric techniques. In 0.5 M KNO 3 solution, at submillimolar concentrations of Tl(I) ions, the CuHCF film reversibly transforms, during electrochemical experiments, from the potassium into the thallium form. For slightly higher (several millimoles) Tl(I) concentrations, the electrochemical and gravimetric responses prove that the CuHCF film behaves as the thallium form only. Its formal potential (E f 0 ), calculated from the dependence of the E f 0 on [Tl(I)], is for [Tl(I)] = 1 M, 0.28 V more positive than that found for the potassium form. Experimental results obtained suggest that in both cases, potassium(I) and thallium(I) ions, exchange in interstitial positions takes place. Since the ionic radii and the hydration parameters of both ions are similar, we concluded that this high affinity of thallium(I) ions with respect to the CuHCF film, 250-100 times higher than that of potassium(I) ion, results from chemical interactions. In consequence, the solubility product of a thallium analogue of copper hexacyanoferrate is much smaller than that of the potassium form. For different forms they are equal to (pK values): 37.8 (K 2 Cu 3 [Fe(CN) 6 ] 2 ), 46.3 (Tl 2 Cu 3 [Fe(CN) 6 ] 2 ), and 17.2 (Cu 3 [Fe(CN) 6 ] 2 ).

Effect of foliar spray of potassium nitrate and calcium nitrate on grasspea (Lathyrus sativus L.) grown in rice fallows.

Abstract: However, there is a possibility of raising another crop as a paira crop in a relay cropping system before the harvest of rainfed lowland rice. Grasspea is suitable for relay cropping with paddy rice (1) and it has potential among grain legumes for its tolerance to dry conditions and its adaptibility to unfavourable environments . Since grasspea in relay cropping with rice suffers from nutrient stresses during the reproductive phase, late application of N is effective in reducing flower and pod drop in legume and in increasing seed yield . Legumes, in general, require K and Ca. This study, therefore, was initiated to investigate the effect of foliar spray of potassium nitrate and calcium nitrate on a paira crop of grasspea grown in rainfed lowland rice fallows.

Solid smokeless propellants and pyrotechnic compositions for rocket and gas generation systems

Abstract: Solid gas generant compositions produce low particulates of the slightly-soluble or insoluble type when combusted. More specifically the solid gas generants and/or ignition compositions are provided which include an effective combination of phase stabilized ammonium nitrate (PSAN) as a oxidizer component and azodiformamidine dinitrate (AZODN) as the fuel component. Most preferably, the AN is phase stabilized with a phase stabilizing effective amount of a phase stabilizer selected from potassium perchlorate (KP) and/or potassium nitrate (KN).

Ionic Conductivity in Binary Solvent Mixtures. 5. Behavior of Selected 1:1 Electrolytes in Ethylene Carbonate + Water at 25 °C

Abstract: Electrolytic conductivity measurements for a number of 1:1 electrolytes, including potassium chloride, potassium nitrate, tetramethylammonium chloride, tetraethylammonium bromide, tetraethylammonium perchlorate, hydrochloric acid, perchloric acid, methanesulfonic acid, p-toluenesulfonic acid, and the potassium salts of methanesulfonic acid and p-toluenesulfonic acid, are reported in binary aqueous mixtures containing 20, 40, 60, and 80 mass % ethylene carbonate at 25 °C. The conductivity data were analyzed by the Fuoss conductance−concentration equation to calculate the limiting molar conductivity Λo, association constant KA, and cosphere diameter R. The limiting ionic conductivities of eight ions were calculated using the known values of potassium and perchlorate ions. Walden products of ions in different compositions of ethylene carbonate + water mixtures were examined with respect to solvent structural effects and ion−solvent interactions.

Viscosity of molten potassium nitrate

Abstract: Potassium nitrate (KNO 3 ) has been suggested as a standard material for the viscosity of molten salts, under moderate to high temperatures. A recently developed oscillating-cup viscometer has been tested up to 760 K, by measuring the viscosity of molten KNO 3 at atmospheric pressure. A detailed analysis of the uncertainty of the measurements, and the comparison with the data reported by other authors, demonstrated that the data obtained had an estimated uncertainty of 2.3%.

Process for preparing potassium nitrate by metathesis method

Abstract: A process for preparing potassium nitrate by metallesis reaction is a cyclic reaction procedure, and includes preparing the initial raw reaction liquid with common saturation point with ammonium nitrate, potassium chloride and water, adidng fresh water and potassium chloride, separating solid potassium nitrate to obtain the first-stage mother liquid, heating, adding ammonium nitrate, negative-pressure evaporation to separate solid ammonium chloride, returning the second-stage mother liquid back to the crystallizing procedure of potassium nitrate, and repeating said steps. Its advantages are low energy consumption, low requirement for purity of raw material, low cost and simple process.

Flue-cured tobacco seedling-cultivating water soluble composite fertilizer and its preparation method

Abstract: A water-soluble compound fertilizer for cultivating seedling of tobacco contains 1-1.5% of zinc sulfate, 0.5-0.8% of ferrous sulfate, 0.4-0.5% of cupric sulfate, 3-4% of borax, 3-7 % of magnesium sulfate, 8-10% of calcium nitrate, 0.4-1% of sodium tripolyphosphate, 0.4-1% of potassium pyrophosphate, 0.5-1% of calgon, 9-16% of potassium dihydrogen phosphate, 7-12% of ammonium dihydrogen phosphate,0.5-3% of potassium sulfate, 33-35% of potassium nitrate, 6-8% of ammonium nitrate, 9-18% of urea, 1-2% of fulvate mixture and 0.5-3% of ethylene diamine tetraecetic acid tetrasodium salt. It is favorable for tabacco seedling to completely absorb said fertilizer, and can meet the requirements for cultivating seedling.

Thermal decomposition of potassium bis -oxalatodiaqua-indate(III) monohydrate

Abstract: Indium (III) is precipitated with oxalic acid in the presence of potassium nitrate maintaining an overall concentration of 0·125 M in HNO3. Chemical analysis of the complex salt obtained indicates the formula, K[In(C2O4)2]·3H2O. Thermal decomposition studies show that the compound decomposes first to the anhydrous potassium indium oxalate and then to the final mixture of the oxides through formation of potassium carbonate and indium (III) oxide as intermediates. Isothermal study, X-ray diffraction pattern and IR spectral data support the proposed thermal decomposition mechanism.

Aerosol fire-extinguishing agent and its prepn

Abstract: The aerosol fire extinguishing agent consists of oxidant barium nitrate and/or potassium nitrate; reductant magnesium powder and/or aluminium powder; additive sodium hydrogen carbonate and pyramine, magnesium carbonate and pyramine, sodium hydrogen carbonate and azoformamide, or magnesium carbonate and azoformamide; and adhesive epoxy resin or phenolic resin. It has the advantages of no environmental pollution, no toxicity to human body, good moistureproof property, homogeneous burning, eliminating flame and reducing temperature.

A process for the production of potassium nitrate

Abstract: A method for the production of potassium nitrate by its salting out from an aqueous solution comprising the ions K?+, C1-, M++? and NO?3?- wherein M++ represents Ca++ and/or Mg++, comprising the following steps; (a) dissolving at least one mineral selected from the group consisting of calcium carbobate, magnesium carbonate, magnesium oxide, calcium oxide, calcium hydroxide, magnesium hydroxide and dolomite, in aqueous nitric acid, in an amount which is approximately stoichiometrically equivalent to the amount of nitrate ions in the solution, or dissolving at least one mineral selected from the group consisting of calcium nitrate and magnesium nitrate, in water; (b) dissolving at least one source for potassium chloride, in the solution obtained at step (a) at temperature higher than 40 °C, wherein the amount of the source is chosen such as to obtain an approximately stoichiometric ratio between potassium and nitrate ions and wherein the source is selected from the group consisting of KC1, carnallite, sylvinite, and a mixture of KC1 with MgC1?2?, NaC1, CaC12 or a combination thereof; (c) cooling the solution obtained at step (b) to obtain a precipitate of potassium nitrate.

Method for the preparation of plant nutrient granules

Abstract: Method for the preparation of granules of inorganic nutrients in which the inorganic nutrient is subjected to a granulation in the presence of a polysaccharide, calcium and nitrate. Preferably a solution of Ca(NO 3 ) 2 in water is used. The nutrient is chosen for example from the group formed by potassium sulphate, magnesium sulphate, ammonium sulphate, potassium nitrate, calcium nitrate, sodium chloride and potassium chloride. The quantity of polysaccharide used usually lies between 0.1 and 10 wt.%, calculated on the total quantity of final product. The invention also relates to granules obtainable with such a method.

Process for increasing concentration of solid-phase potassium nitrate and quality of resultant potassium nitrate

Abstract: A process for increasing concentration of solid-phase potassium nitrate and improving quality of potassium nitride includes preparing crystallizing solution of potassium nitrate from potassium chloride and ammonium nitrate at 70-100 deg.C, cooling in crystallizer, laying aside for 5-15 min, discharging most of upper mother liquid and crystal of ammonium chloride, dewatering the lower residue, andseparating potassium nitrate from mother liquid. The concentration of solid-phase potassium nitrate can reach more than 50%.

Impact of common salts on oxidation of alcohols and chlorinated hydrocarbons

Abstract: Aqueous oxidations of phenol, methanol, ethanol, n-propanol, n-butanol, chloroethanol, chloropropane and chlorobutane were conducted to evaluate the impact of common salts and bases on oxidation with hydrogen peroxide. Oxidation rates increased up to greater than two orders of magnitude, depending on the electrolytes. Sodium and potassium electrolytes generally promoted oxidation at temperatures near 100°C with sodium promoting oxidation better than potassium. Ionic interactions among electrolytes change the nature of their catalytic activity. In the presence of nitric acid, calcium was the most effective of these metals for promoting oxidation. Using soluble salts is proposed for wet-air oxidation and contaminated soil treatment.

Improvements in the sample preparation for the determination of ruthenium in catalysts by different spectrometric techniques.

Abstract: The sample preparation steps of two analytical methods for the determination of ruthenium in carbon supported catalysts with flame atomic absorption spectrometry (FAAS) or UV-vis spectrophotometry, were carefully optimised. As a first step, the carbon support is ignited in air at 450 degrees C then the residue is fused with potassium hydroxide and potassium nitrate to convert ruthenium into ruthenate anion RuO4(2-). The melt is dissolved in water with potassium persulphate and potassium hydroxide as stabilisers. Ruthenium may be directly estimated by measuring the UV-vis molecular absorption of ruthenate at the isosbestic point of the ruthenate-perruthenate mixture or by FAAS. In the latter case, an aliquot of the sample solution is added to the concentrated hydrochloric acid to obtain hexachlororuthenate RuCl6(2-), that is nebulized into the flame after proper dilution. This novel procedure allows to determination of ruthenium without the sensitivity loss (-66%) which occurs in the alkaline media resulting from the fusion. The relative standard deviation is 1.1% for FAAS and 1.3% for UV-vis, at 5% Ru (n = 7). The detection limit (3sB) is 0.07% Ru for FAAS and 0.02% Ru for UV-vis. Both methods were applied to the analysis of a commercial sample and a statistical comparison was carried out.

Process for manufacturing potassium nitrate fertilizer and other metal nitrates

Abstract: A process for producing potassium nitrate and other metal nitrates from the chlorides, sulfates, oxides of these metals The process uses nitrogen dioxide as a true fluidizing medium in shallow beds of the aforementioned solids at moderately elevated temperatures in a continuous counter current process to convert the metal chlorides, sulfates, and oxides, into metal nitrates and effluent gas and water vapor The process may be carried out in a series of true fluidized beds arranged in a vertical configuration so that the solids flow downward due to the fluidized process and the nitrogen dioxide gas flows counter currently in an upward direction producing pure metal nitrates at the bottom and nitrosyl chloride gas and/or water vapor at the top

Composition for promoting nutrition of tree and method for using the same

Abstract: PURPOSE: A nutrient composition supplied to trees is provided to promote the physiological activity and growth of the weakened trees. CONSTITUTION: The composition is prepared by selecting one or more among Potassium nitrate, Ammonium magnesium, Calcium nitrate, Monopotassium Phosphate, Ferric chloride, Kinetin, Pyridoxine, Thiamine, Niacin, IBA and IAA and diluting the selected ingredient with 1-15% of glucose sap, purified distillation or clean water. To improve physiological activity of trees, the nutrient composition is provided to the trees by injecting to the trunk, applying to leaves or ground.

Preparing potassium nitrate by metathesis and crystilization

Abstract: A metathetical reaction crystallization process for preparing potassium nitrate uses potassium chloride and ammonium nitrate as raw materials and features the simultaneous metathetical reaction and crystallization, and crystallization at room temperature. Needing no refrigilating equipment can save both investment and power consumption, prolong the period of cleaning, and change intermittent crystallization into continuous crystallization.

Conversion of low NOx concentrations in combustion gases to nitric acid or fertilizer using hydrogen peroxide and lye

Abstract: A process for reducing NO x emissions in a gaseous combustion effluent stream containing NO and/or NO 2 includes the steps of: a) adding hydrogen peroxide to the effluent stream in sufficient amounts to generate nitric acid by first stage reactions as follows: 2NO+H 2 O 2 +O 2 →2HNO 3 2NO 2 +H 2 O 2 →2HNO 3 2NO+2NO 2 +O 2 +2H 2 O 2 →4HNO 3 ; and optionally, after the nitric acid is generated, adding sufficient amounts of potassium hydroxide to the effluent stream to generate potassium nitrate in second stage reactions as follows: 2HNO 3 +2KOH→2KNO 3 +2H 2 O 4HNO 3 +4KOH→4KNO 3 +4H 2 O.

Nitrate Removal Rate in a Continuous Column Denitrification Reactor Using Hydrogen Generated by Electrolysis with Carbon Anodes and Stainless Cathodes.

Abstract: An autotrophic continuous denitrification process, using hydrogen generated by electrolysis with activated carbon anodes, were experimentally demonstrated to be an effective nitrate removal process. Several fixed bed columns with polypropylene packing and honey-come shaped activated carbon anodes and stainless rod cathodes were set in thermostat chamber of 30°C, and then potassium nitrate enriched tap water, nitrogen concentration of 30mg-N·l-1, was supplied at various flow rates and electric currents. Although the anode is in the same column where microbes grow, sufficient nitrate removal was observed. For example, 94% of nitrate was removed at the HRT of as short as 1.8h for an electrical current of 6mA. A model assuming successive nitrate and nitrite reductions and plug-flow process, nitrate reduction rate=k1[NO3-][H2], and nitrite reduction rate=k2[NO2-][H2]1.5 was constructed. Calculated results with k1=1.3l·mmol-1·h-1 and k2=3.3l1.5·mmol-1.5·h-1 agreed well with the all the experimental results.