Process for the removal of lead and cadmium from phosphoric acid

Details Process for the removal of lead and cadmium from phosphoric acid Process for the removal of lead and cadmium from phosphoric acid

1994-08-01

1995-07-11

Langel, Wayne

Chemistry of inorganic compounds

Phosphorus or compound thereof

Oxygen containing

C01B 2516

Patent

active

054318955

ABSTRACT:
To remove lead and cadmium from phosphoric acid, alkali solution and aqueous sulfide solution are simultaneously introduced with thorough mixing into a phosphoric acid having a P.sub.2 O.sub.5 content of up to 32% by weight, an iron content of up to 0.3% by weight and an alkali/P ratio of up to 0.30. The temperature of the phosphoric acid which is thoroughly mixed with alkali solution and sulfide solution is adjusted to temperatures of 58.degree. to 72.degree. C. with escape of the excess hydrogen sulfide. To complete the sulfide precipitation, the temperature is lowered to below 45.degree. C. Finally, the precipitated sulfides of the lead and cadmium are separated off from the phosphoric acid.

REFERENCES:
patent: 1787192 (1930-12-01), Fiske
patent: 3764655 (1973-10-01), Ehlers et al.
patent: 4134962 (1979-01-01), Ehlers et al.
patent: 4378340 (1983-03-01), Berglund
patent: 4642224 (1987-02-01), Ressel et al.
patent: 4670244 (1987-06-01), Roos et al.
patent: 4769226 (1988-09-01), Winand et al.
patent: 4777028 (1988-10-01), Schrodter

Affiliated with

Also associated with

Rating

Process for the removal of lead and cadmium from phosphoric acid does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Process for the removal of lead and cadmium from phosphoric acid, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for the removal of lead and cadmium from phosphoric acid will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-501732