Burning Rate Studies. IV. Effect of Experimental Conditions on the Consumption Rate of the Liquid System 2-Nitropropane– Nitric Acid

1956 ◽  
Vol 60 (7) ◽  
pp. 904-909 ◽  
Author(s):  
A. Greenville Whittaker ◽  
Harry Williams ◽  
Penniman M. Rust
Keyword(s):  
Nitric Acid ◽  
Burning Rate ◽  
Consumption Rate ◽  
Liquid System ◽  
Experimental Conditions ◽  
System 2

Burning‐Rate Studies. A Negative Pressure Exponent in the Consumption‐Rate Equation for a Liquid System

1957 ◽  
Vol 26 (3) ◽  
pp. 717-718
Author(s):  
A. Greenville Whittaker ◽  
Harry Williams ◽  
Penniman M. Rust
Keyword(s):  
Burning Rate ◽  
Rate Equation ◽  
Negative Pressure ◽  
Consumption Rate ◽  
Liquid System

Kinetics of Alumina Removal from a Calcined Kaolin with Nitric, Sulphuric and Hydrochloric Acids

Clay Minerals ◽  
1970 ◽  
Vol 8 (3) ◽  
pp. 337-345 ◽  
Author(s):  
S. F. Hulbert ◽  
D. E. Huff
Keyword(s):  
Nitric Acid ◽  
Hydrochloric Acid ◽  
Kinetic Data ◽  
Acid Leaching ◽  
Normal Reaction ◽  
Reaction Equation ◽  
Experimental Conditions ◽  
Image Position ◽  
Calcined Kaolin ◽  
Kinetics Of

AbstractAn investigation of the acid-leaching of a calcined kaolin was made to compare the reaction kinetics of hydrochloric, nitric, and sulphuric acids. The acid concentrations used were 5·9 and 8·6 normal. Reaction temperatures used were 95°, 80° and 60° C.Particular attention was given to finding a reaction equation which would mathematically represent the kinetic data. A nucleation rate equation of the general form, was found to represent these data. Values of m varied from 1·10 to 1·55 depending on the experimental conditions.Under the conditions employed the rate of alumina leaching is fastest with hydrochloric acid, slower with sulphuric acid, and slowest with nitric acid. The rate controlling steps are proposed from the experimental evidence.

scholarly journals THE INACTIVATION OF DILUTE SOLUTIONS OF CRYSTALLINE TRYPSIN BY X-RADIATION

1955 ◽  
Vol 38 (5) ◽  
pp. 581-598 ◽  
Author(s):  
Margaret R. McDonald
Keyword(s):  
Sulfuric Acid ◽  
Nitric Acid ◽  
Hydrochloric Acid ◽  
Radiation Effects ◽  
Reaction Yield ◽  
X Rays ◽  
Dilute Solutions ◽  
Experimental Conditions ◽  
Ph Range ◽  
Ph Curve

The proteolytic activity of dilute solutions of clystalline trypsin is destroyed by x-rays, the amount of inactivation being an exponential function of the radiation dose. The reaction yield increases steadily with increasing concentration of trypsin, varying, as the concentration of enzyme is increased from 1 to 300 µM, from 0.068 to 0.958 micromole of trypsin per liter inactivated per 1000 r with 0.005 N hydrochloric acid as the solvent, from 0.273 to 0.866 with 0.005 N sulfuric acid as the solvent, and from 0.343 to 0.844 with 0.005 N nitric acid as the solvent. When the reaction yields are plotted as a function of the initial concentration of trypsin, they fall on a curve given by the expression Y α XK, in which Y is the reaction yield, X is the concentration of trypsin, and K is a constant equal to 0.46, 0.20, and 0.16, respectively, with 0.005 N hydrochloric, sulfuric, and nitric acids as solvents. The differences between the reaction yields found with chloride and sulfate ions in I to 10 µM trypsin solutions are significant only in the pH range from 2 to 4. The amount of inactivation obtained with a given dose of x-rays depends on the pH of the solution being irradiated and the nature of the solvent. The reaction yield-pH curve is a symmetrical one, with minimum yields at about pH 7. Buffers such as acetate, citrate, borate and barbiturate, and other organic molecules such as ethanol and glucose, in concentrations as low as 20 µM, inhibit the inactivation of trypsin by x-radiation. Sigmoid inactivation-dose curves instead of exponential ones are obtained in the presence of ethanol. The reaction yields for the inactivation of trypsin solutions by x-rays are approximately 1.5 times greater when the irradiation is done at 26°C. than when it is done at 5°C., when 0.005 N hydrochloric acid is the solvent. The dependence on temperature is less when 0.005 N sulfuric acid is used, and is negligible with 0.005 N nitric acid. The difficulties involved in interpreting radiation effects in aqueous systems, and in comparing the results obtained under different experimental conditions, are discussed.

Application en série benzofurannique d'un nouveau procédé de nitration par l'acide nitrique en présence de chlorure stannique

1983 ◽  
Vol 61 (10) ◽  
pp. 2287-2290 ◽  
Author(s):  
Jacques Einhorn ◽  
Pierre Demerseman ◽  
René Royer
Keyword(s):  
Nitric Acid ◽  
Stannic Chloride ◽  
Experimental Conditions

A new nitration technique, using nitric acid in the presence of stannic chloride in dichloromethane, has been extended to a series of benzofurans. The ease of performing the reaction as well as the diversity of products that can be obtained under various experimental conditions make it a worthwhile technique. [Journal translation]

scholarly journals Separation of tungsten and rhenium on alumina

2004 ◽  
Vol 69 (8-9) ◽  
pp. 683-688 ◽  
Author(s):  
Jurij Vucina ◽  
Dagoljub Lukic ◽  
Milovan Stoiljkovic
Keyword(s):  
Nitric Acid ◽  
Sodium Chloride ◽  
Aqueous Phase ◽  
Aqueous Media ◽  
Distribution Coefficients ◽  
Experimental Conditions ◽  
Efficient Separation ◽  
Separation Factors ◽  
Ph Range

The conditions for the efficient separation of tungsten(VI) and rhenium (VII) on alumina were established. The distribution coefficients K d for tungstate and perrhenate anions, as well as the separation factors ?(? = KdWO42-/Kd ReO4-) were determined using hydrochloric or nitric acid as the aqueous media. Asolution of sodium chloride in the pH range 2?6 was also examined. Under all the tested experimental conditions, alumina is a much better adsorbent for tungsten than for rhenium. The obtained results indicated that the best separation of these two elements is achieved when 0.01? 0.1 mol dm-3HCl or 1.0mol dm-3 HNO3 are used as the aqueous media. If NaCl is used as the aqueous phase, the best separation is achieved with 0.20 mol dm-3 NaCl pH 4?6. Under these experimental conditions, the breakthrough and saturation capacities of alumina for tungsten at pH4 are 17 and 26 mg W/g Al2O3 respectively. With increasing pH, these values decrease. Thus, at pH 6 they are only 4 and 13 mg W/g Al2O3, respectively.

scholarly journals Extraction and Back-Extraction Behaviors of La(III), Ce(III), Pr(III), and Nd(III) Single Rare Earth and Mixed Rare Earth by TODGA

Sensors ◽  
2021 ◽  
Vol 21 (24) ◽  
pp. 8316
Author(s):  
Lina Qiu ◽  
Jiandi Li ◽  
Weiwei Zhang ◽  
Aijun Gong ◽  
Xiaotao Yuan ◽  
...  
Keyword(s):  
Rare Earth ◽  
Nitric Acid ◽  
Hydrochloric Acid ◽  
Liquid System ◽  
Extraction Time ◽  
Hydrochloric Acid Concentration ◽  
Back Extraction ◽  
Initial Concentration ◽  
Initial Stage ◽  
Acid Type

N,N,N′,N′-Tetraoctyl diglycolamide (TODGA), as a new extraction agent, is effective for its excellent performance and low environmental hazard, and it is very welcome for the rare earth separation process. In this paper, by controlling the extraction time, diluent type, acid type and its concentration, rare earth concentration, etc., the optimum extraction and back-extraction effects of TODGA on La(III), Ce(III), Pr(III), and Nd(III) and mixed rare earths were obtained. The experiment showed that 0.10 mol·L−1 TODGA had the best extraction effect on single rare earth under the conditions of using petroleum ether as diluent, 5 mol·L−1 nitric acid, 20 min extraction time, and 0.01 mol·L−1 rare earth. In the mixed rare earth extraction, the percentage concentrations of La(III), Ce(III), Pr(III), and Nd(III) could be achieved from 21.7%, 19.9%, 30.8%, and 22.2% at the initial stage to 90.5%, 37%, 51%, and 62% after extraction, respectively, by controlling the number of back-extraction cycles and the concentrations of hydrochloric acid and nitric acid in the back-extraction system. The TODGA–rare earth carrier system showed the best back-extraction effect when the hydrochloric acid concentration was 1 mol·L−1 and the back-extraction time was 20 min. At the same time, the mixed rare earth liquid system with low initial concentration was selected for extraction and separation of mixed rare earth. The separation effect was better, and the recovery rate was higher than that of mixed rare earth liquid system with a high initial concentration.

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