Calcium chloride lakes

Calcium Chloride Lakes The Dead Sea, Israel and Jordan... 

One of the most unusual of the world s calcium chloride lakes is Lake Vanda and the nearby Don Juan Pond in Antarctica. The lake is covered with ice, there is nearly fresh water under the ice, and below that a stratified strong calcium chloride... 

Posokhov, E. V. (1949). The Calcium Chloride Lakes of Central Kazakhstan. Doklady Akad. Nauk SSSR 66, 421-423. 

Chlorine. Nearly all chlorine compounds are readily soluble in water. As a result, the major reservoir for this element in Figure 1 is the ocean (5). Chloride, as noted earHer, is naturally present at low levels in rain and snow, especially over and near the oceans. Widespread increases in chloride concentration in mnoff in much of the United States can be attributed to the extensive use of sodium chloride and calcium chloride for deicing of streets and highways. Ref. 19 points out the importance of the increased use of deicing salt as a cause of increased chloride concentrations in streams of the northeastern United States and the role of this factor in the chloride trends in Lake Ontario. Increases in chloride concentration also can occur as a result of disposal of sewage, oil field brines, and various kinds of industrial waste. Thus, chloride concentration trends also can be considered as an index of the alternation of streamwater chemistry by human development in the industrialized sections of the world. Although chlorine is an essential element for animal nutrition, it is of less importance for other life forms. 

The calcium lake of 1,2-dihydroxyanthraquinone is marketed as Pigment Red 83, 58000 1. It is produced commercially by treating a slightly basic alizarin solution with aqueous calcium chloride. 

Manufacture. Sodium carbonate is an important product of the alkali industry. It is obtained naturally by the purification of sal soda which is found in the water of lakes Magadi of Kenya in East Africa, Owens of California in the USA etc. Industrially it is obtained by the Solvay process (ammonia-soda process) sodium chloride solution is saturated by ammonia which is forced into the solution. Carbon dioxide gas is then blown into the solution to form the bicarbonate (NaHCO 3) and ammonium chloride (NH<,.C1). When the bicarbonate is separated and heated, water and carbon dioxide are driven off and sodium carbonate is obtained. The ammonium chloride is mixed with milk of lime and distilled to form calcium chloride and ammonia solution. The recovered ammonia is used repeatedly. 

Economic Importance. Calcium chloride is produced in large quantities as a byproduct in different chemical processes e.g. in the Solvay process or in the production of propene oxide in the chlorohydrin process, of which only a small part is processed to pure calcium chloride. In 1993 in the USA ca. 0.48 10 t (as anhydrous calcium chloride/ was produced mainly from natural sources (mainly subterranean brines and, to a lesser extent, dried out salt lakes in California). 

Sodium occurs widely as NaCl in seawater and as deposits of halite in dried up lakes etc. (2.6% of the lithosphere). The element is obtained commercially by electrolysis of NaCl melts in which the melting point is reduced by the addition of calcium chloride sodium is produced at the iron cathode (the Downs cell). The metal is extremely reactive. It reacts vigorously with the halogens, and also with water to give hydrogen and sodium hydroxide. The chemistry of sodium is very similar to that of the other members of group 1. 

Calcium chloride (1885) n. CaCb. Salt used in the manufacture of some lakes and toners from acid dyestuffs, fireproof paints, sizing compounds, wood preservatives, snow melter, and anti-freeze. 

According to the Colour Index (1971), synthetic calcite can be produced industrially in two ways (1) from conversion of calcium oxide, and (2) as a precipitate of calcium chloride with sodium carbonate. The resultant compound was often used as a base for lake pigments and as an extender for others. However, see calcium carbonates group for a fuller discussion of synthesis. The Colour Index designation for this pigment is Cl 77220/Pigment White 18. The term whiting also may refer to a synthetic calcimn carbonate. 

Examples of the Calcium Chloride Brine in Bristol and Cadiz Lakes... 

Cadiz Lake is located just to the southeast of Bristol Lake at an elevation of 165 m, and also contains a calcium chloride brine in its near-surface sediments. The brine is similar but more dilute than at Bristol Lake, and has a higher ratio of sodium to calcium chloride. However, in other features the two lakes are quite different, and do not appear to have ever been joined as a single lake in a deeper basin. A 152 m core hole (Fig. 2.19) showed that its sediments contain no halite except for one 0.3 m thick bed 2.7 m below the surface, and that its strata are quite different from that at Bristol Lake. The Cadiz basin contains much more gypsum, sand, sUt, and even many fresh and saline water fossils. Near the center of the lake, there is a low area with the above-noted halite close to the surface, surrounded by large areas with an efflorescent surface. However, the northeastern and southern parts of the playa have a fresh water aquifer, and there are some large expanses of dry clay flats which are now utilized for agricultural production. The differences in the lake s sediments would indicate that after the calcium chloride was formed at Bristol Lake, there was a limited period of overflow of sodium and calcium chloride brine into Cadiz Lake, but that during... 

Danby Lake is southeast of Cadiz Lake, and is the last member in the Bristol— Danby Trough. It is 3.2-4.8 km wide by 22.5 km long, at an elevation of 189 m, and the divide between it and Bristol Lake is 152 m high (Fig. 2.17). Its sediments are somewhat similar to Cadiz Lake, but it does not contain any calcium chloride. Its brine and salts are predominately of the sodium chloride-sulfate type (Calzia, 1992), which would have precipitated any calcium chloride that may have overflowed from the other lakes. Danby Lake has had limited commercial production of sodium sulfate, and considerable production of salt (Garrett, 2001). 

The average analyses of seven high-calcium chloride springs to the northeast are listed in Tables 2.6 and 2.10, with the composition of the lake s brine in Table 2.10 (which remains fairly constant throughout the year). It is seen that the seawater-type brine entering from the south results in the precipitation of... 

In Kazakhstan, Russia there are a group of six somewhat similar lakes (listed as a in Table 2.10), with Lake Ushtagan containing a fairly strong calcium chloride brine, and the others having only a modest calcium chloride content. They were all formed by dilute calcium chloride springs (Posokhov, 1949), which almost certainly originated from dolomitization brine formed by the area s extensive potash deposits. 

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