Metal alkyls storage

Preparation of gem-Dinitroalkanes. A methanolic solution of alkali metal hydroxide (Li, Na, or K) was treated with 10% excess nitroalkane and stirred for 30 minutes. The solution was evaporated to dryness in vacuo, and the alkali metal alkyl nitronate was aned over phosphorus pentoxide at reduced pressure (0.1 mm.) for 24 hours. (Caution nitronate salts may be shock sensitive and have been known to explode after prolonged storage.) A slurry of 3.3 grams (0.02 mole) of lithium 1-nitro-cyclohexane in 50 ml. of acetonitrile was cooled to —40°C., and 2.7 grams (0.02 mole) of nitronium tetrafluoroborate were slowly added. The reaction was not exothermic, and the reaction mixture turned brilliant blue upon adding nitronium tetrafluoroborate. The reaction mixture was stirred for 2 hours at —30° to —40°C., then filtered to give a quantitative yield of lithium tetrafluoroborate. The filtrate was quenched into 100... 

Besides AB, some of its derivatives have also been investigated for hydrogen storage, especially to overcome the previously mentioned problems. The derivatives hydrazine borane (HB) [13], guanidinium borohydride (GBH) [12], ethylenediamine bisborane (EDB) [43], methylguanidinium borohydride (Me-GBH) [44], and different alkyl amine boranes are the most interesting (Fig. 40.3) [45, 14]. Another compound class between molecular and metal hydride storage materials is that of metal amido boranes, which is not discussed in this chapter [46]. 

The isopentane for the catalyst preparation unit is stored as a liquid in a 60-ton horizontal (bullet) storage tank. The aluminum alkyls and other required chemicals for this process are received in small truck trailers and kept beneath a metal canopy. 

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