Sequential separation of metals by controlled pH precipitation

Details Sequential separation of metals by controlled pH precipitation Sequential separation of metals by controlled pH precipitation

1990-04-20

1992-07-07

Silverman, Stanley S.

Liquid purification or separation

Processes

Making an insoluble substance or accreting suspended...

210912, 210738, 210727, 423102, 423104, 423142, 423106, C02F 164

Patent

active

051280477

ABSTRACT:
A process for separately removing zinc and iron from acidic wastewater. The process involves adding alkali metal hydroxide to the acidic wastewater (below about pH 4) to achieve a first pH of about 4.8 to at most about 5.4 and precipitate an iron hydroxide-containing precipitate at this pH. The precipitate from the wastewater is separated and then additional alkali metal hydroxide is added to achieve a second pH in the range from about 8.8 to about 9.4. A zinc hydroxide containing precipitate forms at this second pH and is then recovered by filtration.

REFERENCES:
patent: 3800024 (1974-03-01), Forsell et al.
patent: 3886258 (1975-05-01), Cosgrove
patent: 3976743 (1976-08-01), Landucci et al.
patent: 3985858 (1976-10-01), Cosgrove
patent: 4018680 (1977-04-01), Kupfer
patent: 4124462 (1978-11-01), Reinhardt et al.
patent: 4176160 (1979-11-01), Pavonet
patent: 4338200 (1982-07-01), Zeijlstra
patent: 4342653 (1982-08-01), Halverson
patent: 4343706 (1982-08-01), Etzel et al.
patent: 4566975 (1986-01-01), Allgulin
patent: 4610722 (1986-09-01), Duyvesteyn
patent: 4680126 (1987-07-01), Frankard et al.
SULFEX.TM. Heavy Metals Waste Treatment Process, Permutit.RTM. Technical Bulletin vol. XIII, No. 6 (1976).
Kue et al., The Effect of Weak Chelating Agents on the Removal of Heavy Metals by Precipitation Processes, 5 Environmental Progress, No. 3, FIG. 1 (Aug. 1988) (Annotated Version of FIG. 1).
Process Flowsheet for "Heavy Metals Removal" (Aug. 1984).

Affiliated with

Also associated with

Rating

Sequential separation of metals by controlled pH precipitation does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Sequential separation of metals by controlled pH precipitation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Sequential separation of metals by controlled pH precipitation will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1827843