Assertion: crude phosphoric acid | /r/CreatedBy | acidulating
Facets:
Source sentences:
text: A method of removing solid material from crude phosphoric acid produced by acidulating phosphate rock which comprises: treating crude phosphoric acid so formed with a sodium hydroxide-sodium silicate solution whereby to precipitate sodium silico fluoride from said 20 phosphoric acid; removing said sodium silico fluoride from said acid; subjecting said partially clarified acid to an absolute pressure between about 7" and 25" Hg and simultaneously therewith applying heat to evaporate Water whereby to concentrate said acid and precipitate solid material therefrom; and thereafter filtering said concentrated acid whereby to remove said precipitated solid materials and produce a purified concentrated phosphoric acid.