Borate ammonium

Table 9. Aqueous Solubilities of Alkali Metal and Ammonium Borates at Various Temperatures...

Economic Aspects. The potassium, lithium, and ammonium borates are low volume products. Annual production figures are ia the range of hundreds of metric tons. Prices of these borates duting 1985 and 1990 are given ia Table 16. 

On the other hand, metals such as Ta, Nb, Ti, Zr, Al, etc. (the valve metals ) do not exhibit transpassive behaviour, and in appropriate electrolyte solutions film growth at high fields rather than corrosion and/or oxygen evolution is the predominant reaction thus aluminium can be anodised to 500 V or more in an ammonium borate buffer titanium can be anodised to about 400 V in formic acid and tantalum can be anodised to high voltages in most acids, including hydrochloric acid. 

Figure 42. Breakdown voltages for A1 anodized in (1) ammonium borate, (2) ammonium adipate, (3) potassium hydrogen phthalate, and (4) ammonium dihydrogen phosphate.285...

Many borates are known that contain non-metal cations. Examples include the ammonium borates [39], such as the commercial products ammonium pentaborate, NH4[B506(0H)4] 2 H2O, and ammonium tetraborate, (NH4)2 [6405(011)4] 2 H2O, both of which contain isolated borate anions shown above (Figs. 5a and 6a, respectively) [40]. Isolated borate anions containing more than six boron atoms are rare. However, the mineral ammonioborite [(NH4)3[Bi502o(OH)g] 4 H20 = (NH4)20 5 B2O3 2 2/3 H2O), which may be prepared synthetically by prolonged reflux of a saturated solution of ammonium pentaborate, contains the unusual isolated anion [Bi502o(OH)g] , shown in Fig. 10 [41]. This anion is not known to occur in any metal borate, its formation is apparently directed exclusively by the ammonium cations which can donate H-bonds to interstitial water and the borate structural unit. 

These masses contained boric acid, ammonium borate, sulfates of iron and calcium, and (occasionally) magnesium sulfate. 

Ammonium Bichromate(Dichromate). See under Chromates, Bichromates, etc Ammonium Borate. See under Borates Ammonium Bromate, See under Bromates Ammonium Carbamotes. See under Carbamate Ammonium Corbonote. See under Carbonates Ammonium Chlorate. See under Chlorates Ammonium Chloride. See under Chlorides Ammonium Chromate. See under Chromates Ammonium Cobaltlc Hexanitrate. See Ammonium Hexanitrocobaltate... 

BORONCOMPOUNDS - BORON OXIDES, BORIC ACID AND BORATES] (Vol 4) Ammonium borates [12007-89-5]... 

Effective glow retardants for wood are the ammonium phosphates, ammonium borates, boric acid, phosphoric acid, and compounds that yield phosphoric acid during pyrolysis (3,5). ... 

Dr. Gunther Schulze describes an interesting electrolytic condenser in the Electrochemical and Metallurgical Industry, Vol. VII, page 216. The condenser is made up of ten aluminum plates 3 13/16x6/4x1/25 inches, cut as show-n in Fig. 4 and the lugs bent up (Fig. 5) to form the connections. The lugs and about half an inch of the top of the plates were placed in a saturated solution of ammonium borate, and a thick film formed at 500 volts, as indicated by the shaded area in Fig. 5. The purpose of this film is to help insulate the plate where it meets the surface of the electrolyte in the... 

Ammonium borates.—Many borates of ammonium have been described, hut their existence as definite chemical individuals is in most instances doubtful.18 Ammonium tetraborate, (NH4)2B407,4H20, is prepared by cooling a warm solution of boric acid in excess of ammonium hydroxide. It forms tetragonal crystals,19 soluble in 12 times their weight of water at the ordinary temperature. 

Ammonia, alkylamines, and other proton acceptor species can react with boric acid in aqueous or alcoholic solutions to form a wide range of crystalline nomnetal borate salts. Borate salts of aprotic nomnetal cations, such as quaternary ammonium cations, have also been characterized. The ammonium borates are significant commercial products, and the recognition that both protic and aprotic nonmetal cations can stabilize unusual borate anions has led to increased interest in the study of this area. 

---