Chemistry of inorganic compounds – Phosphorus or compound thereof – Oxygen containing
Patent
1989-02-16
1990-03-06
Doll, John
Chemistry of inorganic compounds
Phosphorus or compound thereof
Oxygen containing
423321S, C01B 2516
Patent
active
049064452
ABSTRACT:
A continuous process is indicated for complete removal of organic impurities from and complete decolorization of pre-purified wet-process phosphoric acid which has been purified by an extractive method using an organic solvent, freed from residual hydrofluoric acid by steam stripping and treated with hydrogen peroxide at elevated temperature, which comprises mixing the pre-purified wet-process phosphoric acid and the hydrogen peroxide in a mixing zone at a temperature of from 100.degree. to 200.degree. C., preferably 140.degree. to 160.degree. C., and allowing them to react at this temperature for a further 1 to 4 hours, cooling to from 85.degree. to 90.degree. C. the pre-purified wet-process phosphoric acid treated in this way and pumping it at this temperature with exclusion of air firstly through an activated charcoal bed which has been prepared on the basis of peat and has been steam-activated and has a BET surface area of from 800 to 1000 m.sup.2 /g, and subsequently through a silicon carbide and/or graphite bed while maintaining a pumping rate of less than 0.5 m.sup.3 /h of wet-process phosphoric acid per m.sup.3 of activated charcoal bed.
REFERENCES:
patent: 3993733 (1976-11-01), Irani
patent: 3993736 (1976-11-01), Irani
patent: 4256570 (1981-03-01), Allen et al.
patent: 4279878 (1981-07-01), Maurer et al.
patent: 4297334 (1981-10-01), McConomy et al.
patent: 4330516 (1982-05-01), Winand
patent: 4369169 (1983-01-01), Nineuil et al.
patent: 4452768 (1984-06-01), Gradl et al.
patent: 4503022 (1985-03-01), Majumdar
patent: 4539192 (1985-09-01), Schimmel et al.
patent: 4540558 (1985-09-01), Gradl et al.
patent: 4637922 (1987-01-01), Nakatani et al.
patent: 4643883 (1987-02-01), Borchert et al.
patent: 4713229 (1987-12-01), Schimmel et al.
European Patent Application 0015809, published 9-17-80.
Bettermann Gerhard
Heymer Gero
Kolkmann Friedrich
Schimmel Gunther
Doll John
Hoechst Aktiengesellschaft
Langel Wayne H.
LandOfFree
Continuous process for complete removal or organic impurities fr does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Continuous process for complete removal or organic impurities fr, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Continuous process for complete removal or organic impurities fr will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-46386