Calcium bromide

Calcium bromide (CaBr2) is produced by reacting slaked lime, quicklime or calcium carbonate with either hydrobromic acid or bromine and a reducing agent (e.g. formic acid, formaldehyde). 

The resulting solution is then evaporated under reduced pressure to crystallise the anhydrous salt which is filtered and dried. Alternatively, the concentrated solution is spray-dried to produce a powder [31.8]. Calcium bromide is highly soluble in water (53 % m/m) and produces a dense solution (1.7 kg/1), which is used in oil well packs and completion fluids . 

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Hypobromites, the salts of hypobromous acid, do not keep well because they gradually disproportionate to bromide and bromate. Solutions are best prepared as needed from bromine and alkafl with cooling. Because disproportionation is catalyzed by cobalt, nickel, and copper (70), these impurities should be avoided. SoHd alkaline earth hypobromites, or more properly, bromide hypobromites such as calcium bromide hypobromite [67530-61 CaBr(OBr), have been known for many years, but the pure crystalline hydrates sodium hypobromite pentahydrate [13824-96-9] NaOBr 5H20, and potassium hypobromite tribydrate [13824-97-0], KOBr 3H20, were not described until 1952 (71). Hypobromites are strong bleaching agents, similar to hypochlorites. 

Lithium Chloride. Of the metal haUdes, calcium bromide [7789-41-5] CaBr2, ziac chloride [7646-85-7] ZnCl2, CaCl2, and lithium chloride [7447-41-8] LiCl, (Class 1, nonregenerative) are the most effective for water removal (4). AH are available ia the form of dehquescent crystals. The hydrates of LiCl are LiCl-nH2 O, where n = 1, 2, or 3. Lithium chloride solutions are more stable ia air and less corrosive than the other metal haUdes. The high solubihty of lithium carbonate [554-13-2] Li2C02, usually eliminates scale formation problems (see LiTHlUM COMPOUNDS). 

Calcium bromide (H2O) [62648-72-0, 71626-99-8 (xH20) 7789-41-5 (anhydr)j M 217.9, d 3.35. Crystd from EtOH or Mc2CO. It loses H2O on heating and is anhydrous at 750 then it loses Br. Deliquescent. 

Brom-benzol, n. bromobenzene. calcium, n. calcium bromide, -cyan, n. cyanogen bromide, bromocyanogen. -dampf, tn. bromine vapor, -eisen, n. iron bromide, -fiasche, /. bromine bottle, -fluor, n. bromine fluoride, -gehalt, tn. bromine content, -gold, n. gold bromide, -goldkalium, n. potassium auri-bromide, potassium bromoaurate. bromhaltig, a. contaim ng bromine, Brom-hydrat, n. hydrobromide bromine hydrate. -hydrin, n. bromohydrin. 

Brom-jod, n. iodine bromide, -kalium, n. potassium bromide, -kalzium, n., kalk, tn. calcium bromide, -kampher, tn. bromo-camphor, Pharm.) monobromated camphor, -kohlenstoff, tn. carbon (tetra)bromide. -korper, tn. Colloids) "bromide body (bromide ion), -kupfer, n. copper bromide, lauge, /. bromine lye (solution of sodium hypobromite and bromide made by passing bromine into sodium hydroxide solution), -lithium, n. lithium bromide. -Idsung, /. bro-nune solution, -magnesium, n. magnesium bromide. -metall, n. metallic bromide. 

Mixing Chart for Heavy Brines Using Calcium Bromide and Calcium Chloride Brines and Calcium Chloride Pellets... 

The most commonly encountered inorganic contaminants in waste HBr streams are primarily low level bromide salts such as sodium bromide or calcium bromide. These do not provide a significant challenge to catalytic performance because they are unlikely to enter the catalytic reactor in significant quantities. Instead, the low operating temperature (about 128°C) of the vaporizer would cause them to be retained and concentrated in that vessel. 

C08-0077. Calculate the overall energy change for the formation of calcium bromide from calcium metal and liquid bromine, hi addition to data found in Appendix C and Table 8-4. the following information is needed The bond energy of Bt2 is 224 kJ/mol bromine s enthalpy of vaporization is 30.9 kJ/mol calcium s enthalpy of vaporization is 177.8 kJ/mol. 

Caicium halides are relatively stable there is the possibility of a violent reaction in the presence of a more electropositive alkaline metal eg detonation on impact of a mixture of calcium bromide and potassium. Calcium chloride has a very high enthalpy of solution in water. When dissolved in large quantities in hot water this causes the solution to boil vigorously, creating emissions. 

CeH907- Ca2+ Br- 3 H20 Calcium bromide a-D-glucopyranuronate, trihydrate CAGLUC10 34 347... 

CsHjjOj Ca2+ Br2- 3 H20 a-L-Fucopyranose calcium bromide, trihydrate CBFUCS 34 351... 

C8H1208 Ca2+ Br2- 2 H20 / -D-Fructopyranose-calcium bromide, dihydrate FRUCAB 37 279... 

C6H1206 Ca2+ Br2 3 H20 a-D-Galactopyranose calcium bromide, trihydrate CAGALA10 31 349... 

C6H1206 Ca2+ Br2" 5 H20 myo-Inositol calcium bromide, pentahydrate MYINCA10 31 349... 

Ci2H21012 Ca2+ Br 4 H20 Calcium bromide 4-0-/ -D-galactopyranosyl-D-gluconate, tetrahydrate (calcium bromide lactobionate, tetrahydrate) LACBCB 31 351... 

C12H220u Ca2+ Br2 H20 a, -Trehalose calcium bromide, monohydrate TRECAB 43 342... 

C,2H22Ou Ca2+ Br2" 7 H20 4-0-/ -D-Galactopyranosyl-D-glucopyranose calcium bromide, heptahydrate (lactose calcium bromide, heptahydrate) LACCCB 31 352... 

The results (Figure 7), in this case for succinoglycan, are rather surprising. The transition temperature does not always increase or decrease as a function of the salt concentration, but rather, in some brines, a maximum value is reached after which the transition temperature falls with increasing salinity. This is particularly apparent for the two calcium salts, calcium bromide and chloride, both of which are used extensively in heavy brine drilling fluids. 

The viscosity of xanthan solutions in calcium bromide brines was also measured as a function of temperature. We found that the transition temperature fell rapidly as the concentration of salt was increased, so much so that above 2 molar it fell below that of succinoglycan. 

The relative stabilities of xanthan and Shellflo-S can be reversed. We have made measurements in a number of brines, including calcium bromide (5), and found that xanthan solutions were less stable than those of succinoglycan above about 400g/l (c. 2M). 

The results, shown in Table II, quantify the adverse effect of common well fluid ions on permeability. Especially relevant are the data indicating that even calcium chloride/calcium bromide fluids cause some permeability reduction, although the cause of the adverse interaction is obscure. 

Calcium hydrogen carbonate plus hydrobromic acid yields calcium bromide plus carbon dioxide plus water... 

EXAMPLE 5.3. Predict the charge on a calcium ion and that on a bromide ion, and deduce the formula of calcium bromide. 

By gaining one electron, the bromine atom attains the electron configuration of krypton and also attains a charge of 1-. The two ions expected are therefore Ca + and Br. Since calcium bromide as a whole cannot have any net charge, there must be two bromide ions for each calcium ion hence, the formula is CaBr2. 

A number of water-soluble calcium salts provide convenient vehicles for the administration of therapeutic anions. Probably the most widely encountered is the acetylsalicylate of soluble aspirin (patented 1935) the urea complex of calcium acetylsalicylate (water-solubility 231 gdm-3 at 310K, pH 4.8 (717)) is also widely used. Other examples include calcium bromide and bromolactobionate (sedatives), calcium 2-hydroxy-3-mercapto-l-propanesulfonateaurate(III) (chrysanol, antiarthritic), and calcium Af-carbamoylaspartate (tranquillizer). Calcium iron(II) citrate has been used to remedy iron deficiency - it has the advantage of being stable to air oxidation of the iron(II). The cyclamate anion is certainly not therapeutic, but is relevant here. 

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