Dead Sea

Bromides of sodium, potassium, magnesium and calcium occur in sea water (about 0.07 % bromine) but the Dead Sea contains much more (5% bromine). Salt deposits (e.g. at Stassfurt) also contain these bromides. Silver bromide, AgBr, is found in South America. 

By experimentally determining the ratio of abundances of C and isotope peaks for CO2 dissolved in sea water at various temperatures, a graph can be drawn relating the solubility of CO2 compared with that of CO2 (the ratio described above). On extracting the CO2 from sediment containing the shells (calcium carbonate) of dead sea creatures by addition of acid, a ratio (R) of abundances of CO2 to CO2 can be measured. If this value is read from the graph, a temperature T is extrapolated, indicating the temperature of the sea at the time the sediment was laid down. Such experiments have shown that 10,000 years ago the temperature of the Mediterranean was much as it is now. 

Company and country are as foUows Akzo Chemicals BV, Netherlands (AC) Asahi Chemical, Japan (ASC) Dead Sea Bromine, Israel (DS) Elf... 

Company and country are as follows Dead Sea Bromine, Israel (DS) Dainippon Ink and Chemical, Japan (DI) Dow Chemical USA, United States (DC) Great Lakes, United States (GL) Hitachi, Japan (H) Keil Chemical Div., Ferro Corp., United States (KC) Manac Inc., Japan (MI) Mitsubishi Gas Chemical Co., Japan (MG) Sakamoto Yukuhin Kogyo Co., Ltd., Japan (SY) Teijia, Japan (T) Tohto Kasei Co., Ltd., Japan (TK). 

Material safety data sheets from Ethyl Corp. (EC) and Great Lakes (GL). Product data sheet from Dead Sea Bromine. 

The Brominated Flame Retardants Industry Panel (BFRIP) was formed ia 1985 within the Flame Retardant Chemicals Association (FRCA) to address such concerns about the use of decabromodiphenyl oxide. Siace 1990 the BFRIP has operated as a Chemical Self-Funded Technical Advocacy and Research (CHEMSTAR) panel within the Chemical Manufacturers Association (CMA) (64). As of 1993, members of BFRIP are Ak2o, Amerihaas (Dead Sea Bromine Group), Ethyl Corp., and Great Lakes Chemical. Siace its formation, BFRIP has presented updates to iadustry on a regular basis (65,66), and has pubhshed a summary of the available toxicity information on four of the largest volume brominated flame retardants (67,68) tetrabromo bisphenol A, pentabromodiphenyl oxide, octabromodiphenyl oxide, and decabromodiphenyl oxide. This information supplements that summarized ia Table 11. 

Soluble Salt Flotation. KCl separation from NaCl and media containing other soluble salts such as MgCl (eg, The Dead Sea works in Israel and Jordan) or insoluble materials such as clays is accompHshed by the flotation of crystals using amines as coUectors. The mechanism of adsorption of amines on soluble salts such as KCl has been shown to be due to the matching of coUector ion size and lattice vacancies (in KCl flotation) as well as surface charges carried by the soflds floated (22). Although cation-type coUectors (eg, amines) are commonly used, the utUity of sulfonates and carboxylates has also been demonstrated in laboratory experiments. 

Dead Sea Works Process. The Dead Sea Works, a subsidiary of Israel Chemicals Ltd., aimounced plans ia 1992 to constmct a 25,000 t/yr magnesium plant at Beer-Sheva, Israel. The plant, to be based on Russian camaHite technology, is designed to use an existing potash plant as the source of camaHte. The chlorine by-product can be either Hquefted and sold, or used ia an existing bromine plant. Waste streams from the camaHite process, as well as spent electrolyte from the electrolytic cells, can be returned to the potash plant. 

Occurrence. Magnesium bromide [7789-48-2] MgBr2, is found in seawater, some mineral springs, natural brines, inland seas and lakes such as the Dead Sea and the Great Salt Lake, and salt deposits such as the Stassfurt deposits. In seawater, it is the primary source of bromine (qv). By the action of chlorine gas upon seawater or seawater bitterns, bromine is formed (see Chemicals frombrine). 

Other Processes. Dead Sea Periclase (DSP, Mishor Rotem, Israel) converts magnesium chloride into MgO by spray-roasting, then hydrates the MgO to Mg(OH)2. The Mg(OH)2 is washed and dmm filtered. DSP purchases the brine from Dead Sea Works, which collects and stores enriched brine from the southern margins of the Dead Sea (77). 

Flame-Retardant Filler. Demand has increased for Mg(OH)2 as a nonhalogenated, flame-retardant filler for thermoplastics used in the aerospace, microelectronics, and cable and wire manufacturing industries (90). Producers of nonhalogenated, flame retardant fillers include Kyowa, Aluisuisse-Lonza (Magnifin product line), Morton, and a Dead Sea Periclase/Dead Sea Bromine joint venture (91). 

Dead Seas Periclase Ltd., on the Dead Sea in Israel, uses yet another process to produce magnesium oxide. A concentrated magnesium chloride brine processed from the Dead Sea is sprayed into a reactor at about 1700°C (127,128). The brine is thermally decomposed into magnesium oxide and hydrochloric acid. To further process the magnesia, the product is slaked to form magnesium hydroxide which is then washed, filtered, and calcined under controlled conditions to produce a variety of MgO reactivity grades. A summary of MgO purities, for the various processes is given in Table 20. 

The approximate composition of surface water in the Dead Sea in 1966 (49) was given as 35 g/L calcium chloride 130 g/L magnesium chloride nearly 80 g/L sodium chloride more than 10 g/L potassium chloride nearly 4 g/L bromide and about 1 g/L sulfate. At 400 m depth the bromide concentration was 6 g/L. Bromine in Israel is produced from the Hquors left from potash production and the bromide content of these Hquors is 14 g/L. 

A second source of brine is found in terminal lakes. The Dead Sea in Israel and Jordan is an example of a large terminal lake with almost unlimited supphes of magnesium chloride, potassium chloride, and sodium chloride. Mote than two and a half million tons of potassium chloride ate extracted from the Dead Sea each year. 

Total solar salt, NaCl, produced in the world is 90 million tons. Well over that amount of salt is produced in preconcentration ponds as an intermediate step in the production of other chemicals such as potassium chloride. For example, the Dead Sea faciUties produce 40 million tons of salt each year but sell none because of the high cost of transportation to markets. 

Occurrence. Bromine [7726-95-6] is found in seawater and in underground brine deposits of marine origin (21). Bromine (qv) is also found in Dead Sea brine and is currently being produced there by the Dead Sea Works. 

Besides the oceans, there are vast reserves of magnesium chloride in the Dead Sea Qaidam Basin, China and many salars of South America. 

The Dead Sea has an unlimited reserve of MgCl2. Presently the Arab Potash Co. discharges its MgCl2 brine back to the sea, but its neighbor to the west. The Dead Sea Works, produces MgO from some of thek concentrated briaes. 

Economic Aspects and Uses. Total world production of potassium products is 29,000,000 tons per year (65). Potassium chloride is removed from brine at Moab, and Wendover, Utah, and at Seades Lake, California. Potassium sulfate is made from Great Salt Lake brine by Great Salt Lake Minerals Corp., which is the largest producer of solar potassium sulfate in the wodd. Combined, these U.S. faciUties stiU produce a relatively small percentage of potash fertilizers in the wodd. Production from the Dead Sea, for example, is 10 times greater than production of potassium from brines in the United States. More than 95% of all the potassium produced is used in fertilizer blends. The remainder is converted to other potassium chemicals for industdal use (see Potassium compounds). 

Chemada Fine Chemicals (Israel) Dead Sea Bromine (Israel)... 

Dead Sea Bromine Group (Israel) Dow Chemical Great Lakes Chemical Laporte (UK)... 

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