Borax Subject

In most commercial processes, borax is obtained from lake brines, tincal and colemanite. The primary salt constituents of brine are sodium chloride, sodium sulfate, sodium carbonate and potassium chloride. The percent composition of borax as Na2B40 in brine is generally in the range 1.5 to 1.6%. Borax is separated from these salts by various physical and chemical processes. The brine solution (mixed with mother liquor) is subject to evaporation and crystahzation for the continuous removal of NaCl, Na2C03 and Na2S04, respectively. The hot liquor consists of concentrated solution of potassium salts and borate components of the brine. The insoluble solid particles are filtered out and the liquor is cooled rapidly in continuous vacuum crystallizers under controlled conditions of temperatures and concentrations to crystallize KCl. Cystallization of borax along with KCl from the concentrated liquor must not occur at this stage. KCl is separated from the hquor by filtration. Bicarbonate then is added to the liquor to prevent any formation of sodium... 

Be sure to use the least toxic (fragrance free) detergents possible, and, of course, always avoid chlorine-based bleaches. Natural laundry detergents (which often contain borax), and natural bleaches are available (more and more often right in your grocery store) from brands like Ecover and Seventh Generation, as well as the Web sites below. (While were on the subject of clothes, take whatever hand-me-downs are offered, and don t be shy about asking for more. Most people are thrilled for the chance to recycle.)... 

Other Transient Interactions. The PVA/borax example dealt with the effects of surface exposure of a two-component polymer system to a wetting liquid. We discovered a practical example of this class of phenomena in a plasticized poly (vinyl chloride) (PVC) system. A peculiar plasticizer (tetraethyl methylene bisphosphonate) for PVC has been found (6) which has the unusual property of exuding out of PVC immediately upon exposure to high humidity. The plasticizer quickly re-enters the resin when the humidity is reduced. A film of 60% resin and 40% plasticizer was solvent cast from tetrahydrofuran onto an impedometer bar and was subjected to sudden high humidity exposure. 

Experiment 186. — a) Subject a minute quantity of manganese dioxide to the borax bead test, and note the color of the bead after heating in each flame. 

This study resulted in a series of reports on a comprehensive evaluation of fire-retardant treatments for wood (2-6). One hundred and thirty single chemicals or combinations of chemicals in the form of various salts were evaluated for flame-spread reduction, smoke, and corrosivity. Diammonium phosphate ranked first in reducing flame spread, followed by monoammonium phosphate, ammonium chloride, ammonium sulfate, borax, and zinc chloride. Zinc chloride, although excellent as a flame retardant, promoted smoke and glowing. Ammonium sulfate was the least expensive, but under certain environmental conditions it was corrosive to metals. None of the 130 compositions tested was considered ideal because of the adverse effects on some of the properties of wood. Several reviews of the subject are available and provide additional background material (J, 7-JO). 

Solid or semi-solid samples may require extraction with an aqueous solution to isolate the ionic components in a form suitable for IC. The actual procedures vary widely, depending on the type of sample. For example, meat and sausage products to be analyzed for nitrate and nitrite are first homogenized mechanically, extracted wth a 5 % borax buffer solution in a hot water bath, and then subjected to a precipitation with strong solutions of potassium hexacyano ferrate and zinc sulfate. The aqueous extracts are diluted further with de-ionized water and filtered through a membrane prior to injection. 

L-Arabitol (L-arabinitol) [7643-75-6] M 152,2, m 102 , 103 , [a]s46 -13 (c 5, 8% borax solution). This pentol, which occurs in the urine of pentosuric subjects, is purified by recrystallisation from 90% EtOH or MeOH. It has a higher rotation in the presence of molybdate [aj -130 (c 0.16, acidified molybdate) [Richtmeyer Hudson J Am Chem Soc 73 2249 1957], [Gatzi Reichstein Helv Chim Acta 21 197 1938,Beilstein 1IV 2832.]... 

Solid samples used in x-ray fluorescence analysis include metallurgical specimens, briquetted powders, and borax discs. For quantitative analysis, both standards and unknowns must be in the same matrix and subjected to the same preparation. Because of the limited escape depth of secondary x-rays, particularly in the long-wavelength region, the surface layers must be representative of the entire sample. 

To study boric complexes of carbohydrates in solution the saccharides are dissolved in saturated deuterium oxide solutions of borax and then subjected to NMR spectroscopy (50). The proton spectra of glucose and xylose in presence and absence of borax are shown in Fig. 9. 

Boron compounds such as borax and boric acid are well known fire retardants for cellulosic products [1]. However, the use of boron compounds such as zinc borate, ammonium pentaborate, boric oxide, and other metallo-borates in the plastics industry has become prominent only since the late 1970s. This entry will review the manufacturing, chemical and physical properties, end-use applications, as well as modes of action of major boron compounds as fire retardants in polymers. The subject is also mentioned in the section entitled Flame retardants inorganic oxide and hydroxide systems. ... 

The 10 molecules (47.24%) of water of crystallization in borax are subject to a small normal variation, the mineral losing water slowly during storage. In cases where considerable accuracy of batch composition is desired, it is necessary to determine and make proper adjustment for the actual water content immediately prior to use. This determination is accomplished by fusion or titration, the latter method being preferred. 

It i employed as a pretanning agent for heaw leathers that are to be subjected to vegetable tarmii, because it accelerates penetration of the vegetable tannins . Teiy rapid tannage is reported w hen skins pretanned with formaldehyde are treated with quebracho extract and borax. After... 

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