Carbon CAS

Uses. The United States and Japan account for about three quarters of the world demand for strontium carbonate, ca 150,000 t/yr. In 1993,... 

The decomposition of MgC03 (magnesite) is an interface process [734] between 813—873 K and E = 150 kJ mole-1. In the presence of C02, E was increased to 234 kJ mole-1 but was reduced slightly on the addition of ZnO or NiO. Admixture with CaO reduced the value of E to 54 kJ mole-1. This is a surprising result since the value of E for decomposition [734,753] of the mixed carbonate (Ca, Mg)C03, dolomite, is 220 kJ mole-1, larger than the value for each constituent. The influence of PCOz and of alkali metals on MgC03 decomposition has been the subject of a DTA study [404]. 

The measured uptake of CPA and PTA over the three activated carbons [55] is shown in Figure 6.28, and the trends predicted by the RPA model in Figure 6.27 are at least qualitatively observed. However, at high pH, over the two highest-surface-area carbons (CA and KB), uptake is about half of that predicted by the RPA model. The discrepancy was explained [55] by steric exclusion of the large Pt ammine complexes, believed to retain two hydration sheaths [15,19], from the smallest micropores of the high-surface-area activated carbon. 

Distribution of Aromatic Carbon (Ca), Naphthenic Carbon (Cn), and Paraffinic Carbon (Cp)... 

CHEMICAL NAME = sodium hydrogen carbonate CAS NUMBER = 144-55-8 MOLECULAR FORMULA = NaHC03 MOLAR MASS = 84.0 g/mol... 

Jurisch (Ref 5) patented the use of 4,4 -dihydroxy-3,5 -dinitrobiphenyl or other o-nitrophenol-type dimers, trimers, etc, having recurring benzene nuclei contg OH NOa groups in ortho position to each other for reducing Ca carbonate, Ca phosphate and Mg phosphate scales in steam boilers... 

A solution of 2 (246 mg, 0.9 mmol) in 2.5 mL of a mixture of acetone, water, and sulfuric acid (96 4 0.25) was left at room temperature for 40 min, whereupon the solution was neutralized with solid lead carbonate (ca. 300 mg). The suspension was filtered, the solid was washed with acetone, and to the filtrate water (10 mL) was added. Acetone was evaporated, and the residue was extracted with chloroform. The CHC13 extract was dried (MgS04) and concentrated to dryness to yield 3 (167 mg, 83%). 

Carbonates Ammonium carbonate, [CAS 506-87-6] (NH4)2C03, volatile, white solid, soluble, formed by reaction of NH4OH and CO2 by crystallization from dilute alcohol, loses NH3, C02. and H20 at ordinary temperatures, rapidly at 58 0 ammonium hydrogen carbonate, ammonium bicarbonate, ammonium add carbonate NH4HCO3, white solid, soluble, formed by reaction of NH4OH and excess CCL. This salt is the important reactant in the ammonia soda process for converting sodium chloride in solution into sodium hydrogen carbonate solid. 

Barium carbonate. [CAS 513-77-9). BaC03, white solid, insoluble (Ksp = 5.13 x 10-9), formed (1) by reaction of barium salt solution and sodium carbonate or bicarbonate solution (2) by reaction of barium hydroxide solution and C02. With excess C02 barium hydrogen carbonate, Ba(HC03)2, solution is formed. Barium carbonate decomposes at 1450"C. 

CALCIUM CARBONATE. [CAS I3I7-65-3I- Calcium carbonate, [CAS. 471-34-11- CaCOi, mol wi 100.09. occurs naturally as the principal constituent of limestone, marble, and chalk. Powdered calcium carbonate is produced by two methods on the industrial scale. It is quarried and ground from naturally occurring deposits and in some cases beneftciated. It is also made by precipitation from dissolved calcium hydroxide and carbon dioxide. The natural ground calcium carbonate and the precipitated material compete industrially based primarily on particle size and the characteristics imparted to a product. 

CARBON. (CAS 7440-44-0], Chemical element symbol C. at. no. 6. at. wl. 12.011. periodic table group 14. mp 3.550°C (approximate), bp 4,2893C (approximate), density 3.52 g/cm (diamond at 20 C). 2.25 g/cmJ (graphile at 20 C). The specific gravity of amorphous carbon at 20 C ranges from 1,8 to 2.1, There are two stable isotopes of the element. i C and l3C. and Tour known radioactive isolopes, l0C. "C. IJC, and l5C. Because the half-life laboul 5,760 years) of HC has been established, this isotope is useful for dating ancient documents and materials. 

Lithium carbonate. [CAS 554-l3-2j. LLCOi. mp 72.6CC, slightly soluble in H 0. Lised in glass, enamel, and ceramic formulations, in the cleclrovvinning of aluminum, and in the manufacture of other lithium compounds. The compound also has been used in the treatment of manic-depressive psychoses. 

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