scholarly journals Parameters Affecting the Precipitation of Al Phases from Aluminate Solutions of the Pedersen Process: The Effect of Carbonate Content

2021 ◽  
Author(s):  
Danai Marinos ◽  
Michail Vafeias ◽  
Dimitris Sparis ◽  
Dimitris Kotsanis ◽  
Efthymios Balomenos ◽  
...  
Keyword(s):  
Sodium Carbonate ◽  
Thermodynamic Study ◽  
Effect Of Temperature ◽  
Lower Amount ◽  
Carbonate Content ◽  
High Sodium ◽  
Carbonation Process ◽  
Theoretical Predictions ◽  
Synthetic Solution ◽  
Leaching Solution

AbstractLeaching experiments were performed in calcium aluminate slag with a high-sodium carbonate adaptation of the Pedersen process. A theoretical thermodynamic study of the pregnant leaching solution was conducted to specify the thermodynamically favored species that exist within. Using the HSC 9.0 software, a carbonation process simulation (neutralization of the aluminate solution with CO2 gas) was simulated. Laboratory carbonation experiments were conducted to verify the theoretical predictions. According to the thermodynamic study, at temperatures below 50 °C gibbsite precipitates in the first stages of carbonation and then is transformed to dawsonite. Temperatures over 65 °C favor the direct precipitation of dawsonite. The same route (thermodynamic analysis, carbonation simulation, and experimental verification) was followed by a synthetic solution containing lower amount of sodium carbonate to prove that dawsonite precipitation occurred as a result of the high free carbonate content, to investigate the effect of temperature and to precipitate alumina hydrate phases. Graphical Abstract

Effective removal of Cr(VI) ions from synthetic solution using mixed biomasses: Kinetic, equilibrium and thermodynamic study

2021 ◽  
Vol 40 ◽  
pp. 101905
Author(s):  
A. Saravanan ◽  
P. Senthil Kumar ◽  
Sunita Varjani ◽  
S. Karishma ◽  
S. Jeevanantham ◽  
...  
Keyword(s):  
Thermodynamic Study ◽  
Effective Removal ◽  
Synthetic Solution ◽  
Kinetic Equilibrium

scholarly journals Effect of Sodium Carbonate Concentration in Calgon on Hydrometer Analysis Results

2018 ◽  
Author(s):  
Arshdeep Kaur ◽  
George C. Fanourakis
Keyword(s):  
Sodium Carbonate ◽  
Clay Content ◽  
The Other ◽  
Sodium Hexametaphosphate ◽  
Carbonate Content ◽  
Fine Grained ◽  
Carbonate Concentration ◽  
Dispersing Agent ◽  
Effective Combination ◽  
Dispersing Agents

Calgon (a combination of sodium hexametaphosphate and sodium carbonate) has proved to be the most effective dispersing agent in determining the grain size distribution of fine-grained soils by means of the hydrometer analysis. Previous research on the effect of the sodium hexametaphosphate content of dispersing agents on the clay contents showed that the addition of sodium carbonate to sodium hexametaphosphate increases its dispersing effectiveness. Hence, Calgon 35:7 was used /recommended by many researchers/methods and proved to be the most effective dispersing agent. Although previous work focusing on the effect of varying the concentration of sodium hexametaphosphate in Calgon has been reported, the effect of the concentration of sodium carbonate in Calgon has not been assessed and reported. For this reason, in this investigation a series of hydrometer test analyses were conducted using the 152H and ASTM 152H: E100 hydrometers with Calgon in ratios of 35:0, 35:20 and 35:30.  It was observed that with any increase in sodium carbonate content beyond 7 grams, the percentage clay content actually decreased tremendously in the case of hydrometer 152H. However, for the other hydrometer, Calgon (35:0) proved to be most effective combination. Thus, the increase in the sodium carbonate content in Calgon, beyond 7 g/ litre, is not recommended.

Analysis of Physical and Chemical Features of Sintering Dust and Study of Recycling Treatment

2015 ◽  
Vol 768 ◽  
pp. 350-362
Author(s):  
Bin Pei ◽  
Guang Zhan ◽  
Zhan Cheng Guo ◽  
Jin Tao Gao
Keyword(s):  
Calcium Carbonate ◽  
Potassium Chloride ◽  
Sodium Carbonate ◽  
Calcium Sulfate ◽  
Sodium Carbonate Solution ◽  
Potassium Sulfate ◽  
Water Leaching ◽  
Leaching Experiment ◽  
Leaching Solution ◽  
Physical And Chemical

Several physical and chemical detection methods were used to study the basic properties of sintering dust collected from Baogang Steel Corporation. The result shows that the major constituents of the electrostatic precipitator dust (ESP dust) were KCl, NaCl, Fe2O3 and Fe3O4. Water leaching experiment on the sintering dust had shown that the KCl in the ESP dust could be separated and recovered by water leaching and fractional crystallization. Component analysis of leaching solution showed that the massive calcium sulfate in the leaching solution should be removed first in order to obtain the pure potassium salt. In order to provide theoretical guidance to inhibit the dissolution of calcium ions from the sintering dust, the water leaching experiment of ESP dust and the dissolution behavior of CaSO4 in the potassium chloride, sodium chloride, potassium sulfate and their mixed salt solution were studied. Result showed that, a lower liquid-solid ratio should be chosen in the leaching process to inhibit the dissolution of calcium sulfate dehydrate. Using sodium carbonate solution as a precipitating agent, the influences of the concentration of sodium carbonate solution, reaction temperature, stirring speed on the preparation of the spherical calcium carbonate were studied. Spherical calcium carbonate with good dispersing performance and grain size distribution in nanometer range of less than 10μm was obtained. The production technology of potassium sulfate by double decomposition was sutdied, the results showed that over 80% and 12.76% of the recovery rate of potassium sulfate and potassium chloride ammonium compound fertilizer could be obtained. Furthermore, a potassium recovery process with joint production of spherical calcium carbonate and potassium sulfate was designed. This process is technically viable and considerable in economic benefit.

Effect of conditions in preparing the caustic soda solution on the sodium carbonate content of viscose fibres

1991 ◽  
Vol 22 (5) ◽  
pp. 312-314
Author(s):  
N. T. Butkova ◽  
V. G. Zhuravskii ◽  
T. V. Yushkova ◽  
A. A. Vasyutina ◽  
L. F. Smirnova
Keyword(s):  
Caustic Soda ◽  
Sodium Carbonate ◽  
Caustic Soda Solution ◽  
Carbonate Content ◽  
Soda Solution

Nesting Biology and Seasonality of Long-Horned Bee Eucera nigrilabris Lepeletier (Hymenoptera, Apidae)

Sociobiology ◽  
2016 ◽  
Vol 63 (4) ◽  
pp. 1031 ◽  
Author(s):  
Mohamed Shebl
Keyword(s):  
Calcium Carbonate ◽  
Sodium Carbonate ◽  
Sandy Loam ◽  
Nesting Behavior ◽  
Carbonate Content ◽  
Pollen Load ◽  
Nesting Biology ◽  
Yellow Color ◽  
The Family ◽  
Ground Nesting

We provide information on the nesting behavior, seasonality and nest soli type characteristics of Eucera nigrilabris Lepeletier, 1841 in Egypt. A nest was discovered in a canal bank in Abbis Village, Alexandria, Western Egypt. The species is protandrous, univoltine, ground nesting species. The bees built deep nests about 85cm under the ground and consisted of lined, branched tunnel with many cell. The bees start fly by end of January until end of March and active in winter seasons. The soil of the nest has yellow color, sandy loam texture, low salinty and sodicity, and low calcium carbonate content. The bee distrbiution was influnced by the soil with high content of sodium carbonate. The bees forage on the wild flora of the family Asteraceae carriyng a yellow pollen load. There is no any record of a cleptoparasitism around the nesting area.

Extraction of actinides using N, N, N′, N′-tetraoctyl diglycolamide (TODGA): a thermodynamic study

2006 ◽  
Vol 94 (6-7) ◽  
Author(s):  
S. A. Ansari ◽  
P. N. Pathak ◽  
M. Husain ◽  
A. K. Prasad ◽  
V. S. Parmar ◽  
...  
Keyword(s):  
Nitric Acid ◽  
Acid Medium ◽  
Thermodynamic Study ◽  
Effect Of Temperature ◽  
Nitric Acid Medium ◽  
Extraction Behaviour

SummaryThe effect of temperature on the extraction behaviour of Am(III), Pu(IV) and U(VI) from nitric acid medium was studied employing

New 2-methylenepropylene-bridged cryptands with high sodium ion selectivity: A thermodynamic study of complexation

1995 ◽  
Vol 23 (3) ◽  
pp. 223-231 ◽  
Author(s):  
Krzysztof E. Krakowiak ◽  
Xian Xin Zhang ◽  
Jerald S. Bradshaw ◽  
Cheng Y. Zhu ◽  
Reed M. Izatt
Keyword(s):  
Ion Selectivity ◽  
Thermodynamic Study ◽  
Sodium Ion ◽  
High Sodium

Measurement of the Effect of Temperature on Stress Distribution and Deformation in Multilayer Optical Thin Film Structures

1994 ◽  
Vol 356 ◽  
Author(s):  
Cynthia G. Madras ◽  
P. Y. Wong ◽  
I. N. Miaoulis ◽  
L. M. Goldman
Keyword(s):  
Thin Film ◽  
Plastic Deformation ◽  
Stress Distribution ◽  
Thermal Stresses ◽  
Film Stress ◽  
Effect Of Temperature ◽  
Optical Thin Film ◽  
Melting Temperatures ◽  
Thermal Expansion Coefficients ◽  
Theoretical Predictions

AbstractThis study investigates methods of predicting the deformation and stress distribution in multilayer optical thin film structures. The thin film layers include materials of various thermal expansion coefficients, elastic moduli, and melting temperatures. Each layer is deposited at a different temperature, causing complex thermal and deposition stresses throughout the structure. In addition, since the deposition temperatures of some of the layers are high (>600°C), stress relaxation and plastic flow may occur in materials with low melting temperatures. A combination of theoretical predictions and experimental measurements is used to measure and quantify the deformation caused by residual and thermal stresses in the films as well as any plastic deformation that may have occurred. Results from a model using multilayer plate bending theory to determine the elastic deformation of the device due to thermal stresses are reported. These predictions, as well as a more common method of predicting film stress and curvature, are compared to experimentally measured curvature changes as a function of temperature in the samples. However, when plastic deformation begins to occur at high temperatures, the residual stress and degree of deformation are no longer predictable based on elastic theory alone, and have to be measured experimentally. Plastic deformation in the substrate is discussed as a cause of a high observed curvature following sample heating.

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