497-19-8 Usage
Chemical Description
Different sources of media describe the Chemical Description of 497-19-8 differently. You can refer to the following data:
1. Sodium carbonate is a common chemical used in various industries, including glassmaking and water treatment.
2. Sodium carbonate, also known as washing soda, is a white, odorless powder used in the production of glass, detergents, and other chemicals.
3. Sodium carbonate is a salt that is used to neutralize acidic solutions.
4. Sodium carbonate is a basic compound used in the washing of organic compounds.
5. Sodium carbonate is used to neutralize the reaction mixture.
6. Sodium carbonate is a basic salt used as a neutralizing agent.
7. Sodium carbonate is a salt that is commonly used as a base in organic reactions.
8. Sodium carbonate is a salt that contains sodium and carbonate ions.
Description
Different sources of media describe the Description of 497-19-8 differently. You can refer to the following data:
1. Sodium carbonate, Na2CO3, is a sodium salt of carbonic acid. The pure product appears as a while, odorless powder with a strong alkaline taste. It has high hygroscopicity. It can be easily dissolved in water to form an aqueous solution with moderate alkalinity.
Sodium carbonate has wide applications in various kinds of fields around the world. One of most important application of sodium carbonate is for the manufacturing of glass. Based on statistics information, about half of the total production of sodium carbonate is used for the manufacturing of glass. During the production of glass, sodium carbonate acts as a flux in the melting of silica. In addition, as a strong chemical base, it is used in the manufacturing of pulp and paper, textiles, drinking water, soaps and detergents and as a drain cleaner. In addition, it can also be used for tissue digestion, dissolving amphoteric metals and compounds, food preparation as well as acting as a cleaning agent.
There are generally two ways for the production of sodium carbonate. One is through the reactions between sodium chloride and calcium carbonate (via the ammonia soda (Solvay) process). The other is from sodium carbonate and hydrogencarbonate ores (trona and nahcolite).
2. Sodium carbonate is known as soda ash or washing soda and is a heavily used inorganic compound. Approximately 45 million tons of soda ash are produced globally both naturally and synthetically. Soda ash is obtained naturally primarily from the mineral trona, but it can also be obtained from nahcolite (NaHCO3) and salt brine deposits. Trona is a freshwater sodium carbonate-bicarbonate evaporite, with the formula Na3CO3HCO3 .2H2O. The largest known deposit of trona is located in the Green River area of Wyoming, and other large deposits are found in Egypt’s Nile Valley and California’s Searles basin around the city of Trona. Soda ash is produced from mined trona by crushing and screening the ore and then heating it. Th is produces a soda ash mixed with impurities. Pure soda ash is obtained by dissolving the product and precipitating impurities combined with filtering processes.
Physical Properties
Sodium carbonate is an inorganic salt and therefore the vapour pressure can be considered negligible. It has a melting point of 851°C (CRC Handbook, 1986; The Merck Index, 1983), it decomposes when heated at > 400 °C and therefore a boiling point cannot be determined. soluble in water; insoluble in alcohol; dissolves in acids liberating CO2.The octanol water partition coefficient (log Pow) is not relevant for an inorganic substance which dissociates. The average particle size diameter (d50) of light sodium carbonate is in the range of 90 to 150 μm and of dense sodium carbonate is in the range of 250 to 500 μm.
The monohydrate consists of colorless and odorless small crystals or cystalline powder; orthorhombic structure; refractive index 1.420; hardness 1.3 Mohs; density 2.25 g/cm3; loses water at 100°C becoming anhydrous; very soluble in water; insoluble in ethanol.
The decahydrate consists of transparent crystals; effloresces on exposure to air; density 1.46 g/cm3; decomposes at 34°C; very soluble in water; insoluble in ethanol.
An aqueous solution of sodium carbonate are strongly alkaline.
Chemical Properties
Different sources of media describe the Chemical Properties of 497-19-8 differently. You can refer to the following data:
1. Sodium carbonate is a white, crystalline and hygroscopic powder with a purity of > 98 %. There are two forms of sodium carbonate available, light soda and dense soda. Impurities of sodium carbonate may include water (< 1.5 %), sodium chloride (< 0.5 %), sulphate (< 0.1 %), calcium (< 0.1 %), magnesium (< 0.1 %) and iron (< 0.004 %). The purity and the impurity profile depends on the composition of the raw materials, the production process and the intended use of the product. For example the purity of the pharmaceutical grade must be higher than 99.5 % in Europe.
Sodium carbonate is a strong alkaline compound with a pH of 11.6 for a 0.1M aqueous solution (The Merck Index, 1983; Johnson and Swanson, 1987). The pKa of CO3 2- is 10.33, which means that at a pH of 10.33 both carbonate and bicarbonate are present in equal amounts.
2. Sodium carbonate, Na2C03, also known as soda or soda ash,is the most important of the industrial alkalis. It is a white or grayish-white, lumpy, water-soluble powder that loses its water of crystallization when heated. It decomposes at a temperature of about 852°C (1560°F). It exists in solution only. It is prepared by the combination of carbon dioxide and water.
Uses
Different sources of media describe the Uses of 497-19-8 differently. You can refer to the following data:
1. Sodium carbonate is a kind of important raw material for chemical industry with wide application. It is the important raw material for making glass, soaps, detergents, textiles, leather, spices, dyes, medicines, etc. It can be used for analysis reagents and also used for the pharmaceutical industry and photoengraving. It is widely used in glass, chemicals, paper making, metallurgy, pharmaceutical, and textile as well as food industries. It is TV dedicated reagent. It can be used for the food industry as the neutralizing agent, leavening agents such as for the manufacture of amino acids, soy sauce and pasta such as bread, bread and so on. It can also be prepared to dubbed alkaline and add into pasta to increase the flexibility and ductility. As the detergent, it can be used for wool rinse. It can also be applied to bath salts and pharmaceutical use and also be used as the alkali agent of tanning. Sodium carbonate is most used in industry with a small part using by the civilian. In the soda ash of industry purpose, it is mainly applied to light industry, building materials and chemical industry, accounting for about 2/3: followed by metallurgy, textiles, petroleum, defense, and pharmaceutical. The glass industry is the largest soda consumer sector with each ton of glass consuming 0.2 ton of soda ash. In the chemical industry, it can be used for manufacturing of sodium silicate, sodium dichromate, sodium nitrate, sodium fluoride, baking soda, borax, and trisodium phosphate. In the metallurgical industry, it is mainly used for fluxing agent, mineral flotation agent, and desulfurization agent for steel and antimony. It can also be used as water softener in printing and dyeing industry. In tanning industry, it can be used for the degreasing of raw hides, neutralizing chrome tanned leather and improving the alkalinity of the chrome liquid. It is also used in the production of synthetic detergent additive sodium tripolyphosphate and other sodium salt. It can be used as a buffer, neutralizing agent and dough conditioner. It can be used in cakes and pastas. Make appropriate use it according to actual requirement of production. It is mainly applied to float glass, funnels, optical glass. It can also be used in other sectors of chemical industry and metallurgy industry. It can reduce the flying the alkali dust through application of heavy soda ash, and thus reducing the material consumption, improving the working conditions as well as improving product quality while reducing its erosion on the refractory material to extend the life of the furnace. It is a kind of basic chemical raw material which is widely used in medicine, paper making, metallurgy, glass, textiles, dyes and other industries and can be used as a leavening agent in food industry. It can be used as analytical reagents, dehydrating agent, and battery additives.
2. Soda ash is used in glass making, in production of sodium chemicals (such as sodium chromates, phosphates, and silicates), in the wood pulp industry, in production of soaps and detergents, in oil refining, in water softening, and in refining of nonferrous metals. In its hydrous crystallized form (Na2C03.10H2O), it is known as sal soda,washing soda,or soda crystals, not to be confused with baking soda,which is sodium hydrogen carbonate or sodium bicarbonate (NaHC03). Its monohydrate form(Na2C03·H20) is the standard compound for scouring solutions.
When in solution, sodium carbonate creates less alkalinity than the hydroxides. A 0.1% solution creates a pH of 11;a fully saturated solution is 35%, which has a pH of 12.5.
The safety requirements for sodium carbonate, because of its lower alkalinity, can be considered less demanding than those for the related bicarbonates.
3. Sodium Carbonate is an alkali that exists as crystals or crystalline
powder and is readily soluble in water. it has numerous functions:
an antioxidant, a curing and pickling agent, a flavoring agent, a
processing aid, a sequestrant, and an agent for ph control. it is used
in instant soups to neutralize acidity. it is used in alginate water des-
sert gels to sequester the calcium, allowing the alginate to solubilize.
it is also used in puddings, sauces, and baked goods.
4. Sodium carbonate is also known as washing soda or carbonate of soda, sodium
carbonate is a white crystal or powder made by converting
salt into sodium sulfate, which was followed by roasting with
limestone and coal. It is soluble in water and glycerin but
not alcohol. Sodium carbonate was used as a pH modifier in
toning baths and as the primary alkali in developers used for
gelatin emulsions.
Biological Functions
Sodium carbonate is used as a buffer component in such applications as chromatography, capillary electrophoresis, and enzyme catalysis. Sodium carbonate is widely used in the isolation of cell membranes, membrane proteins, and hydrophobic proteins. A protocol for the isolation of polyamines from cell culture media has been published.
Toxicity
ADI (acceptable daily intake) make no restrictions (FAO/WHO in 1985). LD50 (median lethal dose) is about 6 g/kg (mice-oral).
Soda ash dust has irritation effects on the skin, respiratory and eyes. Long-term exposure to soda solution may cause eczema and dermatitis. Its concentrated solutions can cause burns, necrosis, and even corneal opacity. The maximal allowable concentration of soda ash dust in the air is 2 mg/m3. The operators should wear overalls, door cover, gloves, boots and other protective clothing to protect the respiratory system and skin.
Production method
Sodium carbonate at present is mostly mined from its natural deposits. It also is manufactured syntheticallly by Solvay (or ammonia-soda) process. The natural production of sodium carbonate currently has supassed its synthetic production.
The Solvay process involves a series of partial reactions. The first step is calcination of calcium carbonate to form lime and CO2. Lime is converted to calcium hydroxide. The most crucial step of the process involves reacting brine solution with carbon dioxide and ammonia to produce sodium bicarbonate and ammonium chloride. Sodium bicarbonate converts to sodium carbonate. The calcium hydroxide and ammonium chloride react to form calcium chloride as the by-product. The partial reactions are shown below:
CaCO3 → CaO + CO2
CaO + H2O → Ca(OH)2
2NaCl + 2CO2 + 2NH3 + 2H2O → 2NaHCO3 + 2NH4Cl
2NaHCO3 → Na2CO3 + H2O + CO2
Ca(OH)2 + 2NH4Cl → CaCl2 + 2NH3 + 2H2O
The overall reaction:
CaCO3 + 2NaCl → Na2CO3 + CaCl2
Sodium carbonate was made historically by the Leblanc process. The first commercial production was carried out by the Leblanc process. In this process, sodium chloride was treated with sulfuric acid to produce sodium sulfate and hydrochloric acid. Heating the sodium sulfate with coal and limestone produced a “black ash” that contained sodium carbonate, calcium sulfide, unreacted coal, and calcium carbonate. Sodium carbonate was separated from the black ash by leaching with water. The overall reaction is as follows:
Na2SO4 + 2C + CaCO3 → Na2CO3 + CaS + 2CO2
References
https://en.wikipedia.org/wiki/Sodium_hydroxide#Uses
http://www.essentialchemicalindustry.org/chemicals/sodium-carbonate.html
Occurrence
Ash is a tree found in regions of North America
History
Sodium carbonate, Na2CO3, has been used historically for making glass, soap, and gunpowder. Along with potassium carbonate, known as potash, sodium carbonate was the basis of the alkali industry, which was one of the first major chemical industries. Throughout history, alkalis were obtained from natural sources. Soda ash was also produced by burning wood and leaching the ashes with water to obtain a solution that yielded soda ash when the water was boiled off. The name soda ash originates from the barilla plant, which was used to produce soda ash. The scientific name of this plant is Salsola soda, but it goes by the common names of sodawort or glasswort because the soda produced from it was used in making glass. Barilla is a common plant found in saline waters along the Mediterranean Sea in Spain and Italy.
Barilla was dried and burned to produce soda ash. The depletion of European forests and
international disputes made the availability of alkali salts increasingly uncertain during the
latter part of the 18th century. LeBlanc
proposed a procedure in 1783, and a plant based on LeBlanc’s method was opened in 1791.
Unfortunately, LeBlanc’s association with French Royalty led to the confi scation of the plant
at the time of the French Revolution. Furthermore, confl icting claims for LeBlanc’s method
were made by several other chemists and he never received the reward.
Definition
Different sources of media describe the Definition of 497-19-8 differently. You can refer to the following data:
1. A
dibasic acid formed in small amounts in solution
when carbon dioxide dissolves in
water:
CO2 + H2O?H2CO2
It forms two series of salts: hydrogencarbonates
(HCO3–) and carbonates (CO32-).
The pure acid cannot be isolated.
2. sodium carbonate: Anhydrous sodium carbonate (soda ash, sal soda) is a white powder, which cakes and aggregates on exposure to air due to the formation of hydrates. The monohydrate, Na2CO3·H2O, is a white crystalline material, which is soluble in water and insoluble in alcohol; r.d. 2.532; loses water at 109°C; m.p. 851°C.The decahydrate, Na2CO3·10H2O (washing soda), is a translucent ef?orescent crystalline solid; r.d. 1.44; loses water at 32–34°C to give the monohydrate; m.p. 851°C.Sodium carbonate may be manufactured by the Solvay process or by suitable crystallization procedures from any one of a number of natural deposits, such as:trona (Na2CO3·NaHCO3·2H2O),natron (Na2CO3·10H2O),ranksite (2Na2CO3·9Na2SO4·KCl),pirsonnite (Na2CO3·CaCO3·2H2O),gaylussite (Na2CO3·CaCO3·5H2O).The method of extraction is very sensitive to the relative energy costs and transport costs in the region involved. Sodium carbonate is used in photography, in cleaning, in pH control of water, in textile treatment, glasses and glazes, and as a food additive and volumetric reagent.
Production Methods
Sodium carbonate is produced on all continents of the world
from its minerals. It is present in large deposits in Africa and the United States as either carbonate or trona, a mixed ore of
equal molar amounts of carbonate and bicarbonate. However,
about 70% of the world production of sodium carbonate is
manufactured by the Solvay (ammonia soda) process,
whereby ammonia is added to a solution of sodium chloride.
Carbon dioxide is then bubbled through to precipitate the
bicarbonate (NaHCO3) that is decomposed by heat-producing
sodium carbonate. In the United States. all production is
based on the minerals that contain sodium carbonate. Different
qualities of sodium carbonate are produced: technical,
food, and pharmaceutical grades.
General Description
Sodium carbonate is a water soluble inorganic salt commonly used as a weak base. Its aqueous solution has the ability to uptake carbon dioxide. It can also catalyze the conversion of sewage sludge to liquid fuels.
Flammability and Explosibility
Nonflammable
Biochem/physiol Actions
Buffer component, may be used for the removal of peripheral membrane proteins.
Safety Profile
Poison by intraperitoneal route. Moderately toxic by inhalation and subcutaneous routes. Mlldly toxic by ingestion. Experimental reproductive effects. A skin and eye irritant. It migrates to food from packagmg materials. Can react violently with Al, P2O5, H2SO4, F2, Li, 2,4,6-trinitrotoluene. When heated to decomposition it emits toxic fumes of Na2O
Purification Methods
It crystallises from water as the decahydrate which is redissolved in water to give a near-saturated solution. By bubbling CO2, NaHCO3 is precipitated. It is filtered off, washed and ignited for 2hours at 280o [MacLaren & Swinehart J Am Chem Soc 73 1822 1951]. Before being used as a volumetric standard, analytical grade material should be dried by heating at 260-270o for 0.5hour and allowed to cool in a desiccator. It has a transition point at 450o, and its solubility in water is 21.58% at 20o (decahydrate in solid phase), 49.25% at 35o (heptahydrate in solid phase) and 44.88% at 75o(monohydrate in solid phase) [D.nges in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol I p 987-988 1963]. After three recrystallisations, technical grade Na2CO3 had Cr, Mg, K, P, Al, W, Sc and Ti at 32, 9.4, 6.6, 3.6, 2.4, 0.6, 0.2 and 0.2 ppm respectively; another technical source had Cr, Mg, Mo, P, Si, Sn and Ti at 2.6, 0.4, 4.2, 13.4, 32, 0.6, 0.8 ppm respectively.
Check Digit Verification of cas no
The CAS Registry Mumber 497-19-8 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 4,9 and 7 respectively; the second part has 2 digits, 1 and 9 respectively.
Calculate Digit Verification of CAS Registry Number 497-19:
(5*4)+(4*9)+(3*7)+(2*1)+(1*9)=88
88 % 10 = 8
So 497-19-8 is a valid CAS Registry Number.
InChI:InChI=1/CH2O3.2Na/c2-1(3)4;;/h(H2,2,3,4);;/q;2*+1/p-2
497-19-8Relevant articles and documents
Deshpande, D. A.,Ghormare, K. R.,Jawadekar, V. L.,Deshpande, N. D.
, p. 295 - 302 (1983)
Thermal decomposition of NaHCO3 powders and single crystals. A study by DSC and optical microscopy
Guarini, G. G. T.,Dei, L.,Sarti, G.
, p. 31 - 44 (1995)
The thermal decomposition of four commercial powders and of differently stored single crystals of sodium hydrogen carbonate is studied by power compensation DSC and by optical and FT-IR microscopy. Independently of manufacturer, specified purity and price, the thermal curves of all the commercial powders show a more or less pronounced low temperature peak preceding the one due to the main decomposition. Such small peak is not observed when samples of laboratory recrystallized material are used. However the thermal behaviour of the latter preparation differs remarkably depending on storage conditions: the material kept in closed glass containers decomposes at temperatures higher than those of the material stored in a desiccator in the presence of concentrated H2SO4. The observation by optical microscopy of the behaviour of the surfaces of single crystals coming from different storage conditions when the temperature is raised in a Kofler heater helps the interpretation of the data collected. The mechanism of the decomposition is discussed and the relevant kinetic parameters reported.
Waldbauer, L.,McCann, D. C.,Tuleen, L. F.
, p. 336 - 337 (1934)
Interaction of graphite with hydroxide-salt melts
Zarubitskii,Dmitruk,Zakharchenko
, p. 525 - 528 (2006)
The mechanism and kinetics of graphite dissolution in melts based on sodium hydroxide were studied. The effect of various salt additives on the intensity of the occurring reactions is considered. A method recommended for removal of graphite in the form of remainders of molds and mold cores from titanium casts is described. Pleiades Publishing, Inc., 2006.
Smith, G. F.,Croad, F.
, p. 141 - 142 (1937)
Kinetic studies on the thermal decomposition of aluminium doped sodium oxalate under isothermal conditions
Jose John,Muraleedharan,Kannan,Abdul Mujeeb,Ganga Devi
, p. 64 - 70 (2012)
The kinetics of thermal decomposition of sodium oxalate (Na 2C2O4) has been studied as a function of concentration of dopant, aluminium, at five different temperatures in the range 783-803 K under isothermal conditions by thermogravimetry (TG). The TG data were subjected to both model fitting and model free kinetic methods of analysis. The model fitting analysis of the TG data shows that no single kinetic model describes the whole α versus t curve with a single rate constant throughout the decomposition reaction. Separate kinetic analysis shows that Prout-Tompkins model best describes the acceleratory stage of the decomposition while the decay region is best fitted with the contracting cylinder model. Activation energy values were evaluated by model fitting and model free kinetic methods for both stages of decomposition. As proposed earlier the results favours a diffusion controlled mechanism for the isothermal decomposition of sodium oxalate.
Quantitative kinetic and structural analysis of geopolymers. Part 1. the activation of metakaolin with sodium hydroxide
Zhang, Zuhua,Wang, Hao,Provis, John L.,Bullen, Frank,Reid, Andrew,Zhu, Yingcan
, p. 23 - 33 (2012)
Isothermal conduction calorimetry (ICC) is used here to measure the kinetics of geopolymerisation of metakaolin by reaction with NaOH solution under a variety of conditions. Three exothermic peaks are observed in the calorimetric curve, and are assigned to the dissolution of metakaolin, the formation of geopolymer with disordered or locally ordered structure, and finally the reorganization and partial crystallization of this inorganic polymer gels. For the purpose of further quantifying the ICC data, the geopolymeric reaction products are assumed to have an analcime-like local structure, and their standard formation enthalpies are estimated from the available data for this structure. This assumption enables ICC to be used for the first time in a quantitative manner to determine the real reaction kinetics of geopolymerization. Increasing the NaOH concentration up to a molar overall Na/Al ratio of 1.1 is seen to enhance the reaction extent observed at 3 days, up to a maximum of around 40% in the high liquid/solid ratio systems studied here, and accelerates the crystallization process. However, further addition of NaOH does not give any additional reaction within this period, or any further acceleration. Raising the reaction temperature from 25 °C to 40°C increases the initial reaction rate but has little effect on the final reaction extent, particularly when Na/Al > 1.
Thermal Decomposition of Solid Sodium Bicarbonate
Ball, Matthew C.,Snelling, Christine M.,Strachan, Alec N.,Strachan, Rebecca M.
, p. 3709 - 3716 (1986)
The thermal decomposition of solid sodium bicarbonate has been studied in the temperature range 360-500 K over a range of partial pressures of carbon dioxide.The effect of water vapour has also been studied.Above 440 K the reaction follows contracting-cube kinetics with an activation energy of 32 kJ mol-1 and a frequency factor of 101 s-1.In this temperature range the presence of water or carbon dioxide has little effect on the kinetics.Below 390 K the reaction follows first-order kinetics.In nitrogen, the activation energy is ca. 64 kJ mol-1, the frequency factor is 105 s-1 and water vapour has little effect.High partial pressures of carbon dioxide increase the activation energy to ca. 130 kJ mol-1 and the frequency factor to 1013.5 s-1.The results of microscopic examination generally confirm the kinetics but show that at low temperatures in nitrogen and carbon dioxide the process are different in detail.
Synthesis, spectroscopy, single crystal XRD and biological studies of multinuclear organotin dicarboxylates
Hussain, Shabbir,Ali, Saqib,Shahzadi, Saira,Tahir, Muhammad Nawaz,Shahid, Muhammad,Munawar, Khurram Shahzad,Abbas, Syed Mustansar
, p. 64 - 72 (2016)
Multinuclear organotin(IV) dicarboxylates of the general formula (Me3Sn)2L·H2O (1), (Ph3Sn)2L (2) and Me2SnL[Sn(Cl)2Me2]2 (3) were synthesized by refluxing disodium iminodiacetate hydrate (Na2L·H2O) with Me3SnCl/Ph3SnCl/Me2SnCl2 in methanol. The elemental analysis (C, H and N) data agreed well with the chemical compositions of the products. IR spectroscopy demonstrated a bridging coordination mode of the carboxylate group. 1H NMR spectroscopy suggested a penta-coordinated environment around the tin(IV) center in complexes 1 and 3. The title complex 3 represents one of the very few examples of organotin(IV) carboxylates showing simultaneously coordination with dimethyltin(IV) as well as dichlorodimethyltin(IV) moieties, by substitution and addition reactions, respectively. The 13C NMR spectroscopy demonstrated the carboxylate-metal linkages. EIMS and ESI spectra verified the molecular skeletons of the products 1-3. Thermogravimetric analysis revealed the bimetallic nature of 2. A single crystal XRD study of 3 has shown a predominantly square pyramidal geometry with some trigonal bipyramidal characteristics around each metal center. The novel products exhibited antibacterial/antifungal potential and their minimal inhibitory concentrations (MIC) were also evaluated. In vitro hemolytic studies on human red blood cells indicated a slightly toxic nature of the synthesized complexes.
Fry, H. S.,Schulze, E. L.
, p. 1131 - 1138 (1928)
Easterbrook, W. C.
, p. 383 - 390 (1957)
Tanaka, H.
, p. 521 - 526 (1987)
PbTe nanostructures: Microwave-assisted synthesis by using lead Schiff-base precursor, characterization and formation mechanism
Ahmadian-Fard-Fini, Shahla,Salavati-Niasari, Masoud,Monfared, Azam,Mohandes, Fatemeh
, p. 778 - 788 (2013)
Pure cubic phase lead telluride (PbTe) nanostructures have been produced by using a Schiff-base complex as a precursor in the presence of microwave irradiation. The Schiff base used as ligand was derived from salicylaldehyde and ethylenediamine. The Schiff-base complex was marked as [Pb(salen)]. In addition, the effect of the irradiation time and the type of reducing agent on the morphology and purity of the final products was investigated. The as-synthesized PbTe nanostructures were characterized extensively by techniques like X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The microwave formation mechanism of the PbTe nanostructures was studied by XRD patterns of the products. Although it was found that both ionic and atomic mechanisms could take place for the preparation of PbTe, the main steps were according to the atomic reaction process, which could occur between elemental Pb and Te.
Gorski, A.,Krasnicka, A. D.
, p. 1895 - 1904 (1987)
Worm
, p. 688 - 688 (1897)
Duval, C.,Wadier, C.,Servigne, Y.
, p. 263 - 267 (1959)
Thermal decomposition of copper(II) and zinc carbonate hydroxides by means of TG-MS: Quantitative analyses of evolved gases
Koga,Tanaka
, p. 725 - 729 (2005)
For the quantitative analyses of evolved CO2and H2O during the thermal decomposition of solids, calibration curves, i.e. the amounts of evolved gases vs. the corresponding peak areas of mass chromatograms measured by TG-MS, were plot
The hidden equilibrium in aqueous sodium carbonate solutions - Evidence for the formation of the dicarbonate anion
Zeller, Klaus-Peter,Schuler, Paul,Haiss, Peter
, p. 168 - 172 (2005)
Crossover 13C NMR experiments between [13C]carbonate and [18O]carbonate in aqueous solution confirm the combined action of two oxygen-exchange modes. The isotopomeric carbon dioxides formed in the hydrolysis equilibrium of
Marotta, A.,Saiello, S.,Buri, A.
, p. 193 - 198 (1982)
Thermal Decomposition of Solid Sodium Sesquicarbonate, Na2CO3*NaHCO3*2H2O
Ball, Matthew C.,Snelling, Christine M.,Strachan, Alec N.,Strachan, Rebecca M.
, p. 631 - 636 (1992)
The thermal decomposition of solid sodium sesquicarbonate has been studied at temperatures between 350 and 487 K in nitrogen and carbon dioxide atmospheres.In nitrogen, a single-stage decomposition to sodium carbonate occurs, following Avrami-Erofeyev kinetics (n = 2), with an inflexion at ca. 390 K.The activation energies are 24 kJ mol-1 for the high-temperature region and 58 kJ mol-1 for the low-temperature region.In carbon dioxide above 435 K, the single-stage reaction follows contracting disc kinetics with an activation energy of 29 kJ mol-1.In carbon dioxide at low temperatures, wegscheiderite (Na2CO3*3NaHCO3) and sodium carbonate monohydrate (Na2CO3*H2O) are formed, and this reaction follows first-order kinetics, withb an activation energy of 67 kJ mol-1.Microscopic evidence is also presented.Relationships between the decomposition of sesquicarbonate and other related compounds are discussed.
Galwey, Andrew Knox,Hood, William John
, p. 1810 - 1816 (1979)
Fire retardancy impact of sodium bicarbonate on ligno-cellulosic materials
Bakirtzis,Delichatsios,Liodakis,Ahmed
, p. 11 - 19 (2009)
In this paper, the effect of NaHCO3 as fire retardant additive during pyrolysis and combustion has been investigated. Four different contents (5%, 10%, 15%, and 20% w/w) of NaHCO3 have been tested on Pinus brutia, Laurus nobilis and
Features of the Thermolysis of Li, Na, and Cd Maleates
Avdin, V. V.,Merzlov, S. V.,Nayfert, S. A.,Polozov, M. A.,Polozova, V. V.,Sakthi Dharan, C. P.,Taskaev, S. V.,Zherebtsov, D. A.
, p. 1311 - 1318 (2020/07/21)
Abstract: Processes of the multi-stage decomposition of maleic acid and Li, Na, and Cd maleates in an inert atmosphere are studied via thermal analysis with synchronous analysis of the composition of the released gases. Reaction mechanisms are proposed according to the data on the mass loss stages determined via thermal analysis, gaseous products, and the final solid decomposition products. It is shown that when heated to 700°C, Li and Na carbonates incorporated into the porous carbon matrix are the final products. Above 350°C, cadmium is reduced from oxide to metal and evaporates to form a porous carbon residue as the only product of thermolysis. All carbon products are X-ray amorphous. Maleic acid decomposes completely into gaseous products in the range of 133–239°C. The maleate ion is more stable in the structure of lithium maleate than in free maleic acid, and Na and Cd cations reduce its stability.
METHOD FOR PRODUCING METAL CARBONATE AND CATALYST FOR PRODUCING THE SAME
-
Paragraph 0023; 0024, (2017/08/26)
A method for producing metal carbonate is disclosed. The method includes the following steps of providing a first mixture of metal and a catalyst containing iron, NO groups, and N-containing ligands first; then introducing carbon dioxide to the first mixture to form a second mixture and obtaining a product. The method described here can improve the yield and decrease the cost of metal carbonate production.