BS 4258 discusses phosphoric acid for industrial use. BS 4258-12 is the fifth part of the BS 4258 multi-series and discusses sampling techniques of phosphoric acid for industrial use.
BS 4258-12 applies to orthophosphoric and polyphosphoric acids prepared by thermal and by wet processes, as well as to crystallized phosphoric acids.
The sampling of wet-process acids is particularly difficult because of the frequent presence of a more or less copious precipitate that is not easy to disperse into a suspension.
BS 4258-12 on sampling techniques of phosphoric acid for industrial use is useful for:
Phosphoric acids are generally delivered in large containers or mobile tanks (trucks, wagons, tankers) each of which may form a batch, and, more rarely, in smaller containers (for example, capacity less than 1 000 ml2)).
BS 4258-12 is a guide to sampling techniques concerning the procedure to be followed and the precautions to be observed for the taking, the preparation and the storage of samples from delivery of phosphoric acid for industrial use, with a view to assessing its quality.