# US 4,392,962 A · Process for separating metals from aqueous solutions

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- Number: US 4,392,962 A
- Document ID: US4392962A
- Status: Granted
- Kind: A
- Application number: 06/318,736
- Filed: 1981-11-06
- Granted: 1983-07-12
- Earliest claimed: 1980-11-13
- Assignees: Hoechst Aktiengesellschaft
- Inventors: Klaus Lehr; Gero Heymer; Christian May; Hermann Klein
- Web page: https://patentgrep.com/patent/US4392962A

## CPC

- C22B 11/04: {by wet processes (extraction of metal compounds by leaching in organic solutions C22B3/16; treatment or purification of solutions by liquid-liquid extraction C22B3/26)}
- C01G 5/003: {Preparation involving a liquid-liquid extraction, an adsorption or an ion-exchange}
- C01G 7/003: {Preparation involving a liquid-liquid extraction, an adsorption or an ion-exchange}
- C01G 55/001: {Preparation involving a liquid-liquid extraction, an adsorption or an ion-exchange}
- C22B 3/24: by adsorption on solid substances, e.g. by extraction with solid resins
- C22B 15/0089: {by chemical methods}
- C22B 43/00: Obtaining mercury
- Y02P 10/20: Recycling
- Y10S 210/912: Heavy metal
- Y10S 210/914: Mercury
- C22B: PRODUCTION AND REFINING OF METALS (electrolytic C25); PRETREATMENT OF RAW MATERIALS
- C01G: COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F (metal hydrides {monoborane, diborane or addition complexes thereof} C01B6/00; salts of oxyacids of halogens C01B11/00; peroxides, salts or peroxyacids C01B15/00; thiosulfates, dithionites, polythionates C01B17/64; compounds containing selenium, or tellurium C01B19/00; binary compounds of nitrogen with metals C01B21/06; azides C01B21/08; {compounds containing nitrogen, other non-metals and metal C01B21/082}; metal amides C01B21/092; nitrites C01B21/50; {compounds of noble gases C01B23/0005}; phosphides C01B25/08; salts of oxyacids of phosphorus C01B25/16; carbides C01B32/90; compounds containing silicon C01B33/00; compounds containing boron C01B35/00; compounds having molecular sieve properties but not having base-exchange properties C01B37/00; compounds having molecular sieve and base-exchange properties, e.g. crystalline zeolites, C01B39/00; cyanides C01C3/08; salts of cyanamide C01C3/16; thiocyanates C01C3/20)
- Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS

## Abstract

The invention relates to a process for separating seminoble and/or noble metals from an aqueous solution having compounds of these metals dissolved therein by subjecting the solution to reaction with red phosphorus. More particularly, the solution is conveyed through a zone containing a layer of granular red phosphorus particles with a size of 0.01 to 10 mm, which may be used in admixture with active carbon.

## Claims

### Claim 1

A process for separating a seminoble or noble metal, from an aqueous solution having a compound of a said metal dissolved therein, which comprises: passing said solution through a column subdivided into a plurality of zones, a lower zone containing a layer of active carbon particles having a size of 0.01 to 10 mm and an upper zone containing a layer of granular red phosphorus having a size of 0.01 to 10 mm.

### Claim 2 (depends on 1)

The process as claimed in claim 1, wherein the red phosphorus particles have a size of 0.25 to 1 mm.

### Claim 3 (depends on 1)

The process as claimed in claim 1, wherein the red phosphorus particles have a chemically activated surface area.

### Claim 4 (depends on 3)

The process as claimed in claim 3, wherein the red phosphorus is chemically activated by means of bleaching liquor.

### Claim 5 (depends on 1)

The process as claimed in claim 1, wherein the red phosphorus is used in admixture with active carbon, the thus-admixed active carbon being employed in a proportion of up to 98 weight %.

### Claim 6 (depends on 5)

The process as claimed in claim 5, wherein the thus-admixed active carbon is used in a proportion of 15 to 40 weight %.

### Claim 7 (depends on 5)

The process as claimed in claim 5, wherein the thus-admixed active carbon comprises particles having a size of 0.01 to 10 mm.

### Claim 8 (depends on 5)

The process as claimed in claim 5, wherein the thus-admixed active carbon comprises particles having a size of 0.25 to 1 mm.

### Claim 9 (depends on 1)

The process as claimed in claim 1, wherein the active carbon particles in said layer have a size of 0.25 to 1 mm.