Magnetic separation of particles including one-step-conditioning of a pulp

Patent metadata

Field	Value
Publication number	US-9387485-B2
Application number	US-201313866613-A
Country	US
Kind code	B2
Filing date	Apr 19, 2013
Priority date	Apr 23, 2012
Publication date	Jul 12, 2016
Grant date	Jul 12, 2016

Abstract

The present invention relates to a process for separating at least one first material from a mixture comprising this at least one first material and at least one second material, which comprises contacting of the mixture comprising at least one first material and at least one second material with at least one magnetic particle, or contacting of the mixture comprising at least one first material and at least one second material with at least one magnetic particle and at least one surface-modifying substance at the same time, contacting of the mixture from step (A) with at least one surface-modifying substance, if this has not been done in step (A), so that the at least one first material, the at least one surface-modifying substance and the at least one magnetic particle become attached to one another, and separation of the addition product by application of a magnetic field.

First claim

The invention claimed is:

1. A process for separating at least one first material from a mixture comprising at least one first material and at least one second material, which comprises the following steps:
(A) contacting of the mixture comprising at least one first material and at least one second material with at least one magnetic particle and at least one surface-modifying substance at the same time, so that the at least one first material, the at least one surface-modifying substance and the at least one magnetic particle become attached to one another, and optionally in the presence of at least one dispersant,
(B) optionally, adding at least one dispersion medium to the mixture obtained in step (A) to give a dispersion having a suitable concentration,
(C) separating the addition product from step (A) or (B) from the mixture by application of a magnetic field,
(D) optionally, cleavage of the addition product which has been separated off in step (C) to obtain the at least one first material and the at least one magnetic particle separately.

2. The process according to claim 1 , wherein the first material is a hydrophobic metal compound or coal and the second material is a hydrophilic metal compound.

3. The process according to claim 2 , wherein the at least one hydrophobic metal compound is selected from the group consisting of sulfidic ores, oxidic ores, carbonate-comprising ores, noble metals in elemental form, compounds comprising noble metals and mixtures thereof.

4. The process according to claim 2 , wherein the at least one hydrophilic metal compound is selected from the group consisting of oxidic metal compounds, hydroxidic metal compounds and mixtures thereof.

5. The process according to claim 1 , wherein the surface-modifying substance is a substance of the general formula (I)
A-Z  (I)

where
A is a linear or branched C 2 -C 30 -alkyl, C 3 -C 30 -heteroalkyl, optionally substituted C 6 -C 30 -aryl, optionally substituted C 6 -C 30 -heteroaryl, C 6 -C 30 -aralkyl, and

Z is a group by means of which the compound of the general formula (I) binds to the at least one hydrophobic material.

6. The process according to claim 5 , wherein Z is selected from the group consisting of anionic groups —(X) n —PO 3 2− , —(X) n —PO 2 S 2− , —(X) n —PS 3 2− , PS 2 − , —(X) n —POS − , —(X) n —CO 2 − , —(X) n —C(S)NHOH and —(X) n —S − where X is selected from the group consisting of O, S, NH and CH 2 and n=0, 1 or 2, with, and optionally, cations selected from the group consisting of hydrogen, NR 4 + with R being independently of one another hydrogen and/or C 1 -C 8 -alkyl, hydroxy-substituted C 1 -C 8 -alkyl or -heteroalkyl, alkali- or earth alkali metals.

7. The process according to claim 1 , wherein the at least one magnetic particle is selected from the group consisting of magnetic metals, ferromagnetic alloys of magnetic metals, magnetic iron oxides, hexagonal ferrites and mixtures thereof.

8. The process according to claim 1 , wherein the at least one magnetic particle is selected from the group consisting of
a. iron,
b. cobalt,
c. nickel
d. mixtures of iron, cobalt and/or nickel,
e. NdFeB,
f. SmCo
g. and mixtures of NdFeB and SmCo,
h. magnetite,
i. maghemite,
j. cubic ferrites of the general formula (II)
M 2+ x Fe 2+ 1-x Fe 3+ 2 O 4   (II)

where
M is selected from among Co, Ni, Mn, Zn and mixtures thereof and
x is ≦1,

k. hexagonal ferrites and
l. mixtures thereof.

9. The process according to claim 1 , wherein the dispersion medium is water.

10. The process according to claim 1 , wherein the mixture comprising at least one first material and at least one second material is milled to particles having a size of from 100 nm to 100 μm before or during step (A).

11. The process according to claim 1 , wherein contacting the mixture comprising at least one first material and at least one second material with at least one magnetic particle and at least one surface-modifying substance at the same time in step (A) is achieved by addition of a mixture, of least one magnetic particle and at least one surface-modifying substance.

12. The process according to claim 1 , wherein contacting the mixture comprising at least one first material and at least one second material with at least one magnetic particle and at least one surface-modifying substance at the same time in step (A) is achieved by addition of a dispersion, of least one magnetic particle and at least one surface-modifying substance.

Assignees

• Basf Se

Inventors

• Michailovski Alexej
• Charoensirisomboon Piyada
• Rieger Reinhold
• Domke Imme
• Shishkov Igor
• Wu Hua
• Zhang Xinya
• Morbidelli Massimo

Classifications

• B03C1/01 Primary

  by addition of magnetic adjuvants · CPC title