摘要 |
<p>A method for the manufacture of concentrated phosphorous acid starting from pure P 4 O 6 is disclosed. The P 4 O 6 is hydrolysed, preferably under stirring in water in the presence of a homogeneous Broensted acid catalyst while maintaining in the hydrolysis/reaction medium a pH below 5 whereby the free water level, at the completion of the hydrolysis, is in the range from 0 to 40 %.</p> |