Showing papers on "Potassium nitrate published in 1976"

Method for removal of potassium nitrate from tobacco extracts

Abstract: This disclosure relates to a process for selectively removing and recovering potassium nitrate in a relatively pure state from tobacco, and especially from Burley tobacco stems. The process comprises the steps of (1) contacting tobacco plant parts with water to obtain an aqueous extract and a fibrous tobacco residue, (2) concentrating the extract, (3) cooling the extract, and (4) separating and recovering the potassium nitrate crystals formed therein. The denitrated aqueous extract is recombined with the fibrous tobacco residue as in making reconstituted tobacco and the like. The purified potassium nitrate is suitable without further purification to use as a fertilizer, thus eliminating costly disposal problems.

Corrosion of Mild Steel in Molten Sodium Nitrate–Potassium Nitrate Eutectic

Abstract: The corrosion (oxidation) of mild steel in molten NaNO3–KNO3 eutectic has been investigated at temperatures ranging from 250° to 450°c, for exposure periods up to 8 h. The results of both weight-gain and potential measurements revealed the formation of a passivating film consisting mainly of Fe3O4. The thickening of the oxide film proceeds according to a parabolic law, at a rate depending on the temperature of the melt. The activation energy of the process was estimated to be 71·3 kJ/mol. A break was observed in the parabolic plots at higher temperatures; this may indicate the beginning of the passivation process. The results have been discussed in the light of oxidation kinetics data for iron in both molten nitrates and air at higher temperatures.

Nitrate leaching and adsorption in a krasnozem from Redland Bay, QLD. II. Soil factors influencing adsorption

Abstract: Laboratory determinations of nitrate adsorption from a 0.005M potassium nitrate solution indicated that exclusion occurred in soil from 0-20 cm and that adsorption increased through the subsoil from 0.16 m-equiv./100 g at 45-90 cm to 0.45 m-equiv./100 g between 360 and 600 cm. These profile changes appeared to be related to decreases in organic matter and pH and increases in kaolinite content. Correlation studies showed a strong relation (r = 0.87) between nitrate adsorption and relative net charge as measured by ApH (pHKCl pHH2O) and a negative relation (r = -0.67) with pHH2O. Correlations with sesquioxide fractions were variable and mostly negative.

Insensitive ammonium nitrate

Abstract: The danger of the accidental detonation of large masses of commercial ammum nitrate during handling and storage under normal climatic conditions is reduced by replacing the ammonium nitrate with a solid solution of potassium nitrate in form III ammonium nitrate wherein the potassium nitrate constitutes from more than zero to less than 50 weight percent of the solid solution.

Process for manufacturing a ferroelectric device and devices manufactured thereby

Abstract: A process for manufacturing a ferroelectric device includes the steps of chemically cleaning a substrate, followed by radio frequency etching of the substrate. The substrate is then pre-heated. A first electrical contact is then formed on the substrate, and over a portion of the first electrical contact there is vapor deposited a stable thin film of potassium nitrate. Then a second electrical contact is formed over at least a part of the thin film of potassium nitrate. A covering of silicon monoxide is then vacuum deposited over the assemblage of the first and second electrical contacts and the potassium nitrate. The assemblage is then annealed for approximately twenty-four hours at a temperature of approximately 160° C.

Nitrate leaching and adsorption in a krasnozem from Redland Bay, QLD. III. Effect of nitrate concentration on adsorption and movement in soil columns

Abstract: Nitrate adsorption and movement was studied in soil from depths of 0-15, 40-90 and 160-300 cm. Adsorption was determined at concentrations ranging from 0.5 x 10-3 to 0.5M potassium nitrate and movement by adding 0, 3, 12 and 120 mg nitrogen15 ml of a potassium nitrate solution to packed columns and leaching with deionized water or 0.2M potassium sulphate. In the 0-15 cm soil, nitrate exclusion was evident in both the adsorption and movement studies at low concentrations, but no effect was measured at high concentrations. In the two subsoils, adsorption increased with concentration to 1.9 m-equiv./100 g when equilibrated with 0.5M potassium nitrate. In the subsoils the depth of leaching of nitrate increased with nitrate concentration; the nitrate distribution was skewed; and the rate of nitrate movement was less than that of water. Addition of sulphate to the subsoils resulted in nitrate movement being similar to that of water. The results are discussed in terms of nitrate adsorption. Comparisons with field observations provide further evidence that adsorption is a major process influencing leaching in these soils.

Tobacco refining process

Abstract: A process for refining tobacco for cigarette use so that the end product is free of resin and tar and virtually free of nicotine, which affords economics in the processing procedure. The tobacco is initially steeped in a hot solution of Potassium Metabisulfite (K2 S2 O5) or Potassium Sulphate (K2 SO4) and then boiled in a solution of Potassium Sulfate and Potassium Nitrate. The tobacco is then air dried and sprayed with flavoring material.

Simultaneous automated determination of chloride, nitrite, nitrate, and ammonia in water and wastewater

Abstract: An automated system capable of simultaneous determination of chloride, nitrite, nitrate, and ammonia in about 2 ml of fresh water or wastewater is described. The four compounds are determined using modifications of established colorimetric procedures. Results can be reported at a true rate of five samples per hour with a relative standard deviation at optimum concentrations of less than 2%. Detection limits are 1 ppm Cl for chloride and 1, 5, and 5 ppb N for nitrite, nitrate, and ammonia, respectively. Sample pH adjustment is not required from 0.0002 N H2SO4 (pH 3.7) to 0.005 N NaOH (pH 11.2). Fresh water and wastewater samples were analyzed for nitrite and ammonia by the proposed procedure and by the manual sulfanilic-naphthylamine and nesslerization method. Analysis by the student t-test showed no significant difference between the paired sets of data (P > 0.5). When potable and wastewater samples were spiked with sodium chloride, potassium nitrate, sodium nitrite, and ammonium chloride and analyzed, average recoveries were 99 to 103%.

Formation constants of chlorocadmium(II) and cadmium dichloride in aqueous melts of calcium dinitrate and calcium dinitrate–potassium nitrate

Abstract: Formation constants of [CdCl]+ and CdCl2 in aqueous melts of Ca[NO3]2·xOH2 and Ca[NO3]2·K[NO3]·xOH2(x= 3.5–7) have been determined at 50, 65, and 80 °C from e.m.f. measurements in suitable concentration cells. The results are discussed in terms of a quasi-lattice structure of aqueous melts, and a model is proposed which predicts the dependence of thermodynamic data for [CdCl]+ formation on the temperature and water content of the molten salt.

Ion exchange in fused salts. Part VII. Ion-exchange isotherms for thallium(I)–potassium and rubidium–potassium on crystalline zirconium phosphate in molten thallium nitrate–potassium nitrate and rubidium nitrate–potassium nitrate mixtures at 360 °C

Abstract: Ion-exchange isotherms for Tl+–K+ and Rb+–K+ on crystalline zirconium phosphate in molten Tl[NO3]–K[NO3] and Rb[NO3]–K[NO3] mixtures are almost fully reversible processes which occur in several steps either via a two-phase transition or a solid–solution mechanism. There is a strong dependence of the gradients of the isotherms on the polarisability of the exchanging cations, and some of the equilibrium constants have been calculated.

Germination studies with “hardened” vegetable seed

Abstract: “Hardening” tomato, carrot, and radish seed by means of a 2% solution of potassium nitrate, or by means of three wetting and drying cycles had no effect on final germination percentage; but hardening reduced the time to 50% germination and reduced the spread of germination at 20°c both in vitro and in simulated field conditions. Similar in vitro results were obtained at 6–8°c, except that final germination percentage of untreated tomato and radish seed was significantly lower than treated seed.

Formation constants of chlorocadmium(ii) and cadmium dichloride in aqueous melts of calcium dinitrate and calcium dinitrate-potassium nitrate

Abstract: Formation constants of [CdCl]+ and CdCl2 in aqueous melts of Ca[NO3]2·xOH2 and Ca[NO3]2·K[NO3]·xOH2(x= 3.5–7) have been determined at 50, 65, and 80 °C from e.m.f. measurements in suitable concentration cells. The results are discussed in terms of a quasi-lattice structure of aqueous melts, and a model is proposed which predicts the dependence of thermodynamic data for [CdCl]+ formation on the temperature and water content of the molten salt.