Microstructure Fabricated by Monocrystalline Silicon Anisotropic Etching in Sodium Carbonate and Sodium Bicarbonate Solutions

The a.-c. electrolysis of sodium carbonate solutions at voltages as high as 110, even when arcing occurs on the electrodes, does not cause the evolution of carbon dioxide. In the a.-c. electrolysis of aqueous bicarbonate solutions with platinum electrodes, hydrogen, oxygen and carbon dioxide are evolved freely until all the bicarbonate has been transformed to carbonate, after which the evolution of carbon dioxide ceases and only hydrogen and oxygen are given off. In a.-c. electrolysis of sodium bicarbonate solutions and solutions of the sodium salts of aliphatic acids, a deposit of finely divided platinum is formed on the electrodes. This deposit inhibits the evolution of carbon dioxide, hydrogen and oxygen, but does not affect the current flow. The decomposition potential of bicarbonate solutions in respect to the evolution of carbon dioxide on smooth platinum and with d.c. was found to be 2.2 volts, and of carbonate solutions, 3.5 volts. The anodic discharge potential of HCO3− is − 1.45 to − 1.50 volts, and of CO3−−, − 1.90 to − 1.95 volts. The evolution of carbon dioxide does not appear to cause any polarizing effect on the anode.

Download Full-text

Properties of sodium carbonate-sodium bicarbonate solutions

Journal of Applied Chemistry ◽

10.1002/jctb.5010050206 ◽

2007 ◽

Vol 5 (2) ◽

pp. 72-75

Author(s):

S. G. Bedekar

Keyword(s):

Sodium Bicarbonate ◽

Sodium Carbonate ◽

Bicarbonate Solutions

Download Full-text

Solubility of nitrous oxide in sodium carbonate-sodium bicarbonate solutions at 25.deg. and 1 atm

Journal of Chemical & Engineering Data ◽

10.1021/je60060a006 ◽

1974 ◽

Vol 19 (1) ◽

pp. 89-92 ◽

Cited By ~ 11

Author(s):

Haruo Hikita ◽

Satoru Asai ◽

Haruo Ishikawa ◽

Naoki Esaka

Keyword(s):

Nitrous Oxide ◽

Sodium Bicarbonate ◽

Sodium Carbonate ◽

Bicarbonate Solutions

Download Full-text

The chemistry of uranium. Part XXVII. Kinetics of the dissolution of uranium dioxide powder in a solution containing sodium carbonate, sodium bicarbonate and potassium cyanide

Hydrometallurgy ◽

10.1016/0304-386x(81)90038-4 ◽

1981 ◽

Vol 6 (3-4) ◽

pp. 197-201 ◽

Cited By ~ 7

Author(s):

J.G.H. Du Preez ◽

D.C. Morris ◽

C.P.J. Van Vuuren

Keyword(s):

Sodium Bicarbonate ◽

Sodium Carbonate ◽

Uranium Dioxide ◽

Potassium Cyanide ◽

Dioxide Powder ◽

Kinetics Of

Download Full-text

Defining features in the kinetics of sodium carbonate-bicarbonate solution carbonization and the quality of the resulting sodium bicarbonate crystals

Eastern-European Journal of Enterprise Technologies ◽

10.15587/1729-4061.2021.239157 ◽

2021 ◽

Vol 4 (10(112)) ◽

pp. 38-44

Author(s):

Mykola Porokhnia ◽

Musii Tseitlin ◽

Svitlana Bukhkalo ◽

Vladimir Panasenko ◽

Tetiana Novozhylova

Keyword(s):

Carbon Dioxide ◽

Sodium Bicarbonate ◽

Sodium Carbonate ◽

Diffusion Resistance ◽

Crystal Formation ◽

Gas Velocity ◽

Laboratory Equipment ◽

Gas Consumption ◽

Kinetics Of

This paper reports a study into the influence of temperature and gas consumption on the carbonization kinetics (saturation with carbon dioxide) of sodium carbonate-bicarbonate solution. The study also examined the quality and speed of crystal formation in this process. This research is predetermined by the environmental problems faced by modern enterprises that produce purified sodium bicarbonate – an insufficient degree of carbonization and, as a result, excessive air pollution with carbon dioxide, which did not participate in the reaction during the process. This study addresses these particular issues. As a result of using specialized laboratory equipment, it was found that an increase in the absorbent temperature from 79 to 85 °C leads to a decrease in the maximum degree of carbonization of the solution from 64 to 59 %. In contrast, the quality of the resulting sodium bicarbonate crystals improves but only in the range from 79 to 82 °C. With a further increase in temperature, the quality stabilizes. It is shown that the carbonization rate increases with increasing specific consumption of the absorbent (carbon dioxide) and is characterized by a negative correlation with the value of oversaturation of the absorbent in terms of NaНCO3. The quality of sodium bicarbonate crystals decreases with increasing gas velocity. Thus, it was reasonable to assume that the established dependence of the kinetics of carbonization of Na2CO3 and NaНCO3 solution on the gas velocity in the apparatus is explained by the inhibition of СО2 absorption, which is caused by the diffusion resistance of sodium bicarbonate crystallization. To improve the quality of crystals and the productivity of carbonization by reducing the supersaturation in terms of NaНCO3, it is recommended to introduce a seed crystal in the zone of binding of crystals in the carbonization columns.

Download Full-text