Borate hydrate, dehydration

High Dehydration Temperature - In contrast to other forms of zinc borates, the water of hydration of the zinc borate is retained up to 290°C, thus allowing it to be used in polymers requiring high processing temperatures. The proposed molecular structure for the zinc borate is depicted in Fig. 

Borax pentahydrate (also known as Neobor ) is the most common form of sodium borate used in a variety of industries. Its advantages when compared with borax lie in the lower transportation, handling, and the storage cost of a more concentrated product. Borax pentahydrate readily effloresces upon heating. It starts to dehydrate at about 65°C, loses all water of hydration when heated above 320°C, and fuses when heated above 740°C. In water, it hydrolyzes to give a mildly alkaline solution with excellent buffering properties.7... 

Firebrake zinc borates display an interaction with metal oxide partieles resulting from dehydrating metal hydrates in flame retardant polyolefins. The interactions taking place show that surface... 

These thermal effects associated to the hydrolysis reaction have been studied on a fully dehydrated NaBH4 powder by means of an IR imaging camera and a differential titration calorimeter. Various amounts of solid sodium hydroxide were added to the system (NaBH4 -I- metallic nanoCobalt catalyst) allowing an increase of the maximum reaction temperature (up to 140 °C). The reaction maximum temperature and the hydrogen yield were considerably modified by varying the amount of NaOH and the amount of catalyst (Fig. 11.13). At a temperature of more than 140 °C, it is reasonable to expect the formation of low hydration borate phases. In fact, at temperatures above 105 °C water is expected to participate preferentially in the hydrolysis reaction rather than in the hydration of the... 

Purification anhydrous hydrazine can be prepared by treating hydrazine hydrate with BaO, Ba(OH)2, CaO, NaOH, or Na. Treatment with sodamide has been attempted but this yields diimide, NaOH, and ammonia. An excess of sodamide led to an explosion at 70 °C. The hydrate can be treated with boric acid to give the hydrazinium borate, which is dehydrated by heating. Further heating gives diimide. ... 

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