Borates, Perborates and Tetraborates

Sodium tetraborate Na2B407 (borax) and sodium perborate NaB03-4H20, both rather soluble in water, are part of the formulation of washing powders. They are also used in glass making, for wax emulsions and gums. 

Whether dry or in solution, these products have practically no action on aluminium, even at high temperamres (80 °C and above). At 20 °C, the decrease in thickness of 5754 in a solution of 5% tetraborate is 10 fim per year. These products are stored and transported in aluminium alloy equipment. 

Aluminium borate 2A1203-B203-3H20, even very humid, does not attack aluminium. 

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