Production of pure alkali metal phosphate solutions from wet-pro

Details Production of pure alkali metal phosphate solutions from wet-pro Production of pure alkali metal phosphate solutions from wet-pro

1975-12-15

1978-07-11

Thomas, Earl C.

Chemistry of inorganic compounds

Phosphorus or compound thereof

Oxygen containing

423305, C01B 1516, C01B 2526

Patent

active

041002610

ABSTRACT:
Production of pure alkali metal phosphate solutions by neutralizing wet-processed phosphoric acid with an alkali liquor and/or carbonate. To this end, the wet-processed phosphoric acid is neutralized to a pH from 4 to 9, the resulting neutralization sludge consisting substantially of insoluble aluminum and iron phosphates is separated from the alkali metal phosphate solution and scrubbed with water, the sludge so treated is mixed with alkali liquor, alkali metal phosphate solution and water-glass so as to establish in the resulting suspension a molar ratio of SiO.sub.2 to Al.sub.2 O.sub.3 of at least 2 : 1 and a molar ratio of dissolved alkali metal oxide to dissolved P.sub.2 O.sub.5 ranging from 2.9 : 1 to 3.3 : 1, the whole is heated to temperatures from 80.degree. to 100.degree. C to effect breakup of the sludge in the suspension with the resultant formation of a solid matter residue together with a trialkali metal phosphate solution, the solid matter residue is separated from the trialkali metal phosphate solution, water-scrubbed, and discarded. More particularly, crude wet-processed phosphoric acid containing more than 45 weight % of P.sub.2 O.sub.5 is diluted with a portion of the scrubbing water obtained during operation and its P.sub.2 O.sub.5 -content is thereby reduced down to 30 to 45 weight %. The acid so treated is neutralized with an alkali liquor and/or carbonate and with the trialkali metal phosphate solution originating from the processed neutralization sludge.

REFERENCES:
patent: 3637346 (1972-01-01), Ehlers et al.
patent: 3764655 (1973-10-01), Ehlers et al.

Affiliated with

Also associated with

Rating

Production of pure alkali metal phosphate solutions from wet-pro does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Production of pure alkali metal phosphate solutions from wet-pro, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Production of pure alkali metal phosphate solutions from wet-pro will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-262562