EP0550483A1

EP0550483A1 - Process for extracting by flotation the minerals contained in non-pyritiferous ores

Info

Publication number: EP0550483A1
Application number: EP91916056A
Authority: EP
Inventors: Berthold Schreck; Rita Köster; Reinhard Bunte
Original assignee: Henkel AG and Co KGaA
Current assignee: Henkel AG and Co KGaA
Priority date: 1990-09-24
Filing date: 1991-09-16
Publication date: 1993-07-14
Also published as: CA2092440A1; AU8510191A; FI931267A; TR25169A; FI931267A0; MX9101215A; WO1992004981A1; DE4030160A1; ZA917574B

Abstract

Des sels de produits d'estérification de l'acide maléique avec des esters partiels d'oligoglycérine, ayant la formule (I), dans laquelle R1, R2, R3 et R4 représentent indépendamment les uns des autres hydrogène, un résidu acyle aliphatique saturé ayant 8 à 18 atomes de carbone ou un résidu CO-CH=CH-COOX; X désigne un métal alcalin ou ammonium et N est égal à 0 ou est compris entre 1 et 18, à condition qu'au moins un des substituants R1 à R4 représente un résidu acyle et au moins un de ces substituants représente un résidu CO-CH=CH-COOX, sont utiles, éventuellement mélangés à d'autres agents tensioactifs anioniques ou non ioniques, comme collecteurs lors de la flottation de minerais non sulfurés, notamment l'apatite.Salts of maleic acid esterification products with partial oligoglycerin esters, having the formula (I), in which R1, R2, R3 and R4 independently of one another represent hydrogen, a saturated aliphatic acyl residue having 8 to 18 carbon atoms or a residue CO-CH = CH-COOX; X denotes an alkali metal or ammonium and N is equal to 0 or is between 1 and 18, provided that at least one of the substituents R1 to R4 represents an acyl residue and at least one of these substituents represents a CO-CH residue = CH-COOX, are useful, optionally mixed with other anionic or nonionic surfactants, as collectors during the flotation of non-sulfurized ores, in particular apatite.

Description

Process for the extraction of minerals from non-sulfidic ores by flotation

The invention relates to a process for extracting minerals from non-sulfidic ores by flotation, in which salts of esterification products of maleic acid with oligoglycerol partial esters, optionally in a mixture with other anionic or nonionic surfactants, are used as collectors.

Flotation is a generally used sorting process for separating valuable minerals from the gangue, which is used to prepare mineral ores. Usually, the ore is first ground and dry, but preferably wet, and suspended in water. Subsequently, a collector is added, often in conjunction with other reagents, which include foaming agents, regulators, pushers (deactivators) and / or Beieber (activators), to separate the valuable minerals from the gangue minerals in the ore during the subsequent flotation supports. Before air is blown into the suspension in order to generate foam on its surface and to start the flotation, these reagents are usually allowed to act on the finely ground ore for a certain time (conditioning). The collector causes the surface of the minerals to become hydrophobic, so that these minerals adhere to the gas bubbles formed during the aeration. The hydrophobization of the mineral Ingredients are selected in such a way that the undesirable components of the ore do not adhere to the gas bubbles and remain behind, while the mineral-containing foam is stripped off and further processed. The aim of the flotation is to extract the valuable mineral of the ores in the highest possible yield and at the same time to obtain the best possible enrichment of the valuable mineral.

In the flotative processing of non-sulfidic ores, mainly anionic or cationic surfactants are used as collectors. These have the task of adsorbing as selectively as possible on the surface of the valuable minerals in order to ensure a high concentration in the flotation concentrate. In addition, the collectors should develop a stable, but not too stable, flotation foam.

The collectors frequently used in the flotation of non-sulfidic ores, such as. B. fatty acids or alkyl sulfosuccinates [Aufberei¬ tionstechnik, 26, 632 (1985)], but in many cases do not lead to a satisfactory yield of valuable minerals with economically justifiable collector quantities.

The object of the invention was therefore to provide collectors with improved properties in the sense of a more economical design of the flotation process.

The invention relates to a process for the extraction of minerals from non-sulfidic ores by flotation, in which ground ore is mixed with water to form a suspension, air is introduced into the suspension in the presence of a reagent system and the resulting foam together with the foam contained therein separates floated solids, and also as a collector

Salts of esterification products of maleic acid with oligoglycerol partial esters which follow the formula (I),

Rl-0-CH2-CH-CH ₂ -0- [CH2-CH-CH ₂ ] n-0-R ² (I)

I I

0-R ³ 0-R ⁴

in the

R, R ² , R ³ and R ⁴ independently of one another are hydrogen, a saturated aliphatic acyl radical having 8 to 18 carbon atoms or a CO-CH = CH-COOX radical,

X is an alkali metal or ammonium and n is 0 or numbers from 1 to 18

with the proviso that at least one of the substituents R to R ^ is an acly radical and at least one is a CO-CH = CH-COOX radical.

The use of salts of the formula (I) in which n is from 2 to 5 and R ^{1 is a} saturated acyl radical having 12 to 18 carbon atoms is particularly advantageous for the flotation.

In the sense of the present invention, salt-type minerals, e.g. B. fluorite, Scheelite, barite, apatite, iron oxides and other metal oxides, e.g. B. to understand the oxides of titanium and zirconium, as well as certain silicates and aluminosilicates. The salts of the esterification products of maleic acid with oligoglycerol partial esters are known substances and can be prepared by the relevant methods of preparative organic chemistry. For example, one can convert oligoglycerols, ie self-condensation products of glycerol with average degrees of condensation from 2 to 20, with fatty acids to oligoglycerol partial esters that still have free hydroxyl groups, esterify one or two of these OH functions with maleic acid, and the Then neutralize the non-esterified acid functions of the dicarboxylic acid component with an aqueous alkali solution. Corresponding methods are in Seifen-Öle-Fette-Wwachs 104, 3 (1978) and Parfum.Kosm. 60, 37 (1979).

Typical fatty acids which may be present as components in the salts of the formula (I) are caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, pal itic acid and stearic acid. As usual in fat chemistry, the fatty acids can also be present as technical mixtures, such as those found in B. after pressure splitting of natural fats and oils (eg coconut oil, palm oil, palm kernel oil, rapeseed oil, sunflower oil or beef tallow) and subsequent hardening.

The reaction of the fatty acid with the oligoglycerin leads to a statistical mixture of esters of different substitution patterns. For the production of oligoglycerol partial esters, oligoglycerin and fatty acid are used in a molar ratio of 1: 1 to 1: 2. Under these conditions, the resulting esterification products according to formula (I) have at least one primary fatty acid ester group. According to the number of free hydroxyl groups in the resulting oligoglycerol partial esters, there follows subsequent esterification with maleic acid or maleic anhydride, likewise statistical laws. If primary hydroxyl groups are still present, it can be assumed that these are the first to be esterified. The reaction of partial oligoglycerin esters and maleic acid takes place in a molar ratio of 1: 1 to 1: 2. The formation of oligoglyceryl esters which are bridged via a maleic acid residue is also possible, albeit a minor one. The salts of these esterification products to be used according to the invention thus represent complex mixtures.

The process according to the invention permits the use of the salts of esterification products of maleic acid with oligoglycerol partial esters as collectors for the extraction of minerals from non-sulphide ores by flotation alone or in the presence of further anionic or nonionic surfactants.

For the purposes of the invention, anionic surfactants are to be understood as meaning fatty acids, alkyl sulfates, alkyl ether sulfates, alkyl sulfosuccinates, alkyl sulfosuccinamates, alkyl benzene sulfonates, alkyl sulfonates, petroleum sulfonates, acyl lactylates, sarcosides, alkyl phosphates and alkyl ether phosphates. All of these anionic surfactants are known compounds, the preparation of which - unless otherwise stated - e.g. in J. Falbe, U. Hasserodt (ed.), "Catalysts, surfactants and mineral oil additives, Thieme Verlag, Stuttgart, 1978 or J. Falbe (ed.)" Surfactants in Consumer Products ", Springer Verlag, Berlin, 1986 is.

The fatty acids here are, in particular, the vegetable or animal fats and oils, for example by fat splitting and optionally fractionation and / or separation after the Crosslinking process, straight-chain fatty acids of the formula (II) into consideration,

R ⁵ -C00Y (II)

in which V \ - represents an aliphatic hydrocarbon radical having 12 to 18 carbon atoms and 0, 1, 2 or 3 double bonds and Y represents an alkali metal, alkaline earth metal or an ammonium radical. The sodium and potassium salts of oleic and tall oil fatty acids are of particular importance.

Suitable alkyl sulfates are the water-soluble salts of sulfuric acid half-esters of fatty alcohols of the formula (III)

in which represents a linear or branched alkyl radical having 8 to 22, preferably 12 to 18 carbon atoms and Z represents an alkali metal or an ammonium radical.

Suitable alkyl ether sulfates are the water-soluble salts of sulfuric acid semiesters of fatty alcohol polyglycol ethers of the formula (IV)

R7- (0CH CH) _n 0S0 ₃ Z (IV)

I.

R ^β

in the R? represents a linear or branched alkyl radical having 8 to 22, preferably 12 to 18 carbon atoms, hydrogen or a methyl group and n represents 1 to 30, preferably 2 to 15 and Z has the meaning given above. Suitable alkylsulfosuccinates are sulfosuccinic acid monoesters of fatty alcohols of the formula (V)

R ⁹ -00C-CH ₂ -CH-C00Z (V)

I.

S03Z

in which R ^ represents a linear or branched alkyl radical having 8 to 22, preferably 12 to 18 carbon atoms and Z has the meaning given above.

Suitable alkylsulfosuccinamates are sulfosuccinic acid monoamides of fatty amines of the formula (VI),

RiO-NH-OC-CH ^ CH-COOZ (VI)

I SO3Z

in the R ^ O for a linear or branched alkyl radical with 8 to

22, preferably 12 to 18 carbon atoms and Z has the meaning given above.

Suitable alkylbenzenesulfonates are substances of the formula (VII)

R ¹¹ -C6H4-S03Z (VII)

in which R ^{11 represents} a straight-chain or branched alkyl radical having 4 to 16, preferably 8 to 12 carbon atoms and Z has the meaning given above.

Suitable alkyl sulfonates are substances of the formula (VIII)

R ¹² -Sθ3Z (VIII) in which R * 2 represents a straight-chain or branched alkyl radical having 12 to 18 carbon atoms and Z has the meaning given above.

Suitable petroleum sulfonates are substances which are obtained by reacting lubricating oil fractions with sulfur trioxide or oleu and then neutralizing with sodium hydroxide solution. Products in which the hydrocarbon residues predominantly have chain lengths of 8 to 22 carbon atoms are particularly suitable here.

Suitable acyl lactylates are substances of the formula (IX)

13_CO-0-CH-COOZ (IX)

I.

CH ₃

in which R ^{13 represents} an aliphatic, cycloaliphatic or alicyclic, optionally substituted with hydroxyl groups, hydrocarbon radical having 7 to 23 carbon atoms and 0, 1, 2 or 3 double bonds and Z has the meaning given above. The production and use of acyl lactylates in flotation is described in DE-A-3238060.

Suitable sarcosides are substances of the formula (X)

CH ₃

I.

R ¹ -C0-H-CH ₂ -C00H (X)

in which R * represents an aliphatic hydrocarbon radical having 12 to 22 carbon atoms and 0, 1, 2 or 3 double bonds. Suitable alkyl phosphates and alkyl ether phosphates are substances of the formulas (XI) and (XII)

and

R ¹⁵ - (0CH ₂ CH ₂ ) p0 0

P (XII)

/ \ ZO OZ

in which R-- and R ¹ ^ independently of one another represent an alkyl or alkenyl radical with 8 to 22 carbon atoms and p and q in the case of the alkyl phosphates for zero, in the case of the alkyl ether phosphates for numbers from 1 to 15 and Z has the meaning given above be¬ sits.

If the salts to be used according to the invention are used in a mixture with alkyl phosphates or alkyl ether phosphates, the phosphates can be present as mono- or diphosphates. In this case, preference is given to using mixtures of mono- and dialkylphosphates as are obtained in the industrial production of such compounds.

For the purposes of the invention, nonionic surfactants are to be understood as meaning fatty alcohol polyglycol ethers, alkylphenol polyglycol ethers, fatty acid polyglycol esters, fatty acid amide polyglycol ethers, fatty amine polyglycol ethers, mixed ethers, hydroxy mixed ethers and alkyl glycosides. All of these nonionic surfactants are Known compounds whose preparation - unless otherwise stated - for example in J.Falbe, U. Hasserodt (ed.), "Catalysts, surfactants and mineral oil additives, Thieme Verlag, Stuttgart, 1978 or J.Falbe (ed.)" Surfactants in Consu er Products ", Springer Verlag, Berlin, 1986.

Suitable fatty acid alcohols are addition products of an average of n moles of ethylene and / or propylene oxide with fatty alcohols, which follow the formula (XIII),

R17 (OCH ₂ CH) _Π OH (XΠI)

I.

R8

in which R * 7 represents a linear or branched alkyl radical having 8 to 22, preferably 12 to 18 carbon atoms, hydrogen or a methyl group and n represents numbers from 1 to 30, preferably 2 to 15.

Suitable alkylphenol polyglycol ethers are addition products of an average of n moles of ethylene and / or propylene glycol with alkylphenols which follow the formula (XIV)

Rl8-C ₆ H4- (0CH ₂ CH) _n 0H (XIV)

!

R ^β

in which R * 8 represents an alkyl radical having 4 to 15, preferably 8 to 10 carbon atoms and R ⁸ and n have the meanings given above. Suitable fatty acid polyglycol esters are adducts of an average of n moles of ethylene and / or propylene oxide with fatty acids which follow the formula (XV)

R ¹ 9-C0 (0CH ₂ CH) _n 0H (XV)

in which R ¹ ^ represents an aliphatic carbon radical having 5 to 21 carbon atoms and 0, 1, 2 or 3 double bonds and R and n have the meanings given above.

Suitable fatty acid amide polyol ethers are addition products of an average of n moles of ethylene oxide and / or propylene oxide onto fatty acid amides which follow the formula (XVI)

R20-C0-NH (0CH ₂ CH) _n 0H (XVI)

in which R ^ O represents an aliphatic hydrocarbon radical having 5 to 21 carbon atoms and 0, 1, 2 or 3 double bonds and RÖ and n have the meanings given above.

Suitable fatty amine polymer ethers are addition products of an average of n moles of ethylene oxide and / or propylene oxide onto fatty acids which follow the formula (XVII)

R ¹ -HH (0CH ₂ CH) _n 0H (XVII)

in which R21 represents an alkyl radical having 6 to 22 carbon atoms and R8 and n have the meanings given above. Suitable mixed ethers are reaction products of fatty alcohol polyglycol ethers with alkyl chlorides of the formula (XVIII)

R ²² - (0CH ₂ CH) _n -0-R ²³ (XVIII)

I R8

in which R ^{22 represents} an aliphatic carbon radical having 6 to 22 carbon atoms and 0, 1, 2 or 3 double bonds, R ²³ represents an alkyl radical having 1 to 4 carbon atoms and R and n have the meanings given above.

Suitable Hroxroxy mixed ethers are substances of the formula (XIX)

R ² -CH-CH ₂ - (0CH ₂ CH) _n -0-R ²⁵ (XIX)

I I

OH R8

in which R ^{24 represents} an alkyl radical having 6 to 16 carbon atoms, R 5 represents an alkyl radical having 1 to 4 carbon atoms and R ⁸ and n have the meanings given above. The preparation of the hydroxy mixed ethers is described in German patent application DE-A-37 23 323.

Substances of the formula (XX) are suitable as alkyl α-coscosides,

R ²⁶ -0- (G) _x (XX)

in which G represents a symbol for a glycose unit derived from a sugar with 5 or 6 carbon atoms, x for a number between 1 and 10 and R ^ for an aliphatic hydrocarbon radical with 6 to 22 carbon atoms and 0, 1, 2 or 3 double bonds. G is preferably a Glucose unit and x for numbers from 1.1 to 1.6. The preparation of the alkyl glycosides is described, for example, in German patent application DE-A-3723826.

If the salts of esterification products of maleic acid with oligoglycerol partial esters are not used alone, but in a mixture with other anionic or nonionic surfactants, these mixtures advantageously have a content of 5 to 95% by weight, preferably 10 to 60% by weight, of the salts of esterification ¬ products of maleic acid with oligoglycerol partial esters.

To achieve economically useful results in the floating of non-sulfidic ores, the surfactant mixture must be used in a certain minimum amount. However, a maximum amount of surfactant mixture must not be exceeded, since otherwise the foam formation becomes too strong and the selectivity towards the valuable minerals decreases.

The amounts in which the salts of esterification products of maleic acid to be used according to the invention with oligoglycerol partial esters or their mixtures with other anionic or nonionic surfactants are used depend on the type of ores to be floated and on their content of valuable minerals. Accordingly, the amounts required in each case can vary within wide limits. In general, the salts of esterification products of maleic acid to be used according to the invention with oligoglycerol partial esters or their mixtures with anionic or nonionic surfactants in amounts of 50 to 2000, preferably 100 to 1500 g, per ton of crude ore. The method according to the invention includes the use of reagents customary for flotation, such as foaming agents, regulators, activators, deactivators, etc. The flotation is carried out under the conditions of the prior art methods. In this context, reference is made to the following references on the technological background of ore processing: H.Schubert, "Processing solid mineral substances", Leipzig, 1967; DBPuchas (Ed.), "Solid / liquid separation equipment scale-up", Croydon, 1977; ESPerry, CJVanOss, E. Grush a (Ed.), Separation and Purification Methods, New York, 1973-1978.

A preferred field of application of the method is the flotation of salt-type minerals, in particular apatite ores.

The following examples are intended to explain the subject matter of the invention in more detail:

Examples

I. Collectors and co-collectors used

A) Collector of the general formula (I)

The composition of the collectors of the general formula (I) used

Rl-0-CH ₂ -CH-CH2-0- [CH2-CH-CH ₂ ] _n -0-R ² (I) 0-R ³ 0-R ⁴

can be seen in Tab. 1.

Tab. 1: Composition of the collectors used

R ¹ R ² R ³ R ⁴ n

A2 C12 / 14-CO H CO-CH = CH-COONa CO-CH-CH-COONa 0

A3 C12 / 14-CO H H C0-CH = CH-C00Na 0

A4 C12 / 14-CO C12 / 14-CO C0-CH = CH-C00Na C0-CH = CH-C00Na 0

A5 C12 / 14-CO H CO-CH = CH-COONa CO-CH = CH-COONa 3

A6 C _{_8/10} -C0 HH CO-CH = CH-COONa 3

A7 C12 / 14-CO H H CO-CH = CH-COONa 3

A8 Cs / io-OHH CO-CH = CH-COONa 0 B) Co-collector

Bl) alkyl sulfosuccinate Na / NH4 salt based on maleic acid mono-oleyl / cetyl (l: l) ester

B2) oleic acid sodium salt, iodine number 95, Edenor ( ^R ) ATiOs (crude), from Henkel

B3) oleic acid sodium salt, iodine number 98, based on beet oil (new cultivation with approx. 90% by weight oleic acid)

C) pusher

Cl) Phenol-formaldehyde condensation product Suspendol ( ^R ) PPK, from Henkel

II. Preparation of the Salts of Esterification Products of Maleic Acid with Oliqoqlvcerinestern

Na salt of a maleic acid half-ester of diglycerol ono laurate (A3). 498 g (3 mol) of technical diglycerol were placed in a 1-1-necked three-necked flask with stirrer, reflux condenser, water separator and internal thermometer, and 625 g (3 mol) of a technical lauric acid (C chain distribution: 2% by weight CJO _» 72 wt .-% Ci2 _ι ² 6 wt .-% (44) The reaction mixture was heated to nitrogen at a temperature of T = 180 to 200 ° C over a period of t = 4 h, the The crude esterification product was then heated under reduced pressure of 15 mbar for a further 2 h at 180 to 200 ° C. The diglycerol monolaurate obtained showed the following key figures:

Hydroxyl number: 420 saponification number: 167

Acid number: 0.8

54.9 g (0.56 mol) of maleic anhydride were added in portions to 200 g (0.56 mol) of the diglycerol monolaurate obtained at a temperature of 60 to 70 ° C. and the mixture was stirred at 100 ° C. for 3 h. The resulting acidic maleic acid half-ester of diglycerol monoaurate was then neutralized with aqueous sodium hydroxide solution and adjusted to pH = 7. Na salt of the maleic acid half-ester of the pentaglycerin mono-Cg / io fatty acid ester (A6). Analogous to the preparation of A3, 776 g (2 mol) of technical pentaglycerol were mixed with 309 g (2 mol) of a Cβ / io fatty acid mixture (C chain distribution: 2% by weight C-, 60% by weight Cg, 35% by weight. % Cio, 3% by weight (2) firstly reacted for 7 hours at 180 to 200 ° C. and normal pressure and then for 1 hour at 180 to 200 ° C. and a reduced pressure of 15 mbar. The partial pentaglycerol fatty acid ester showed the following key figures :

Hydroxyl count: 612 saponification number: 108 acid number: 0.3

207 g (0.4 mol) of the pentaglycerol partial ester obtained were then reacted with 39.2 (0.4 mol) of maleic anhydride at 100 ° C. for 3 h and subsequently neutralized.

III. Flotation experiments in the modified Hallimond tube

Examples 1-10, Comparative Examples VI-V4

Flotation of Swedish apatite ore. A Swedish apatite ore with the following composition, based on the main components, was used as the flotation task:

The ore was already ground up in the slurry. After wet sieving, a particle size fraction of 50-100 μm was used as the task. A modified Hallimond tube with a volume of 165 ml and a stirring speed of 400 rpm was used as the flotation cell. 2 g of ore (dry content) were conditioned and floated at pH 10 (adjusted with sodium hydroxide) in water at 20 ° d (calcium ions only). The conditioning time for the hardening water was 5 minutes, for the collector 10 minutes; the flotation was carried out over a period of 2 minutes.

The collectors according to the invention were used alone or in a mixture with the co-collectors (alkyl sulfosuccinate sodium salt, B1 and oleic acid sodium salt, B2); B1 and B2 were also used individually as reference substances. The results are summarized in Table 2. Examples 1-10 show that salts of esterification products of maleic acid with oligoglycerol partial esters can advantageously be used both as collectors, but in particular as co-collectors in a mixture with other anionic or nonionic surfactants in the flotation of non-sulfidic ores.

Tab. 2: Flotation of Swedish apatite ore in the modified halli tube; Percentages as% by weight

E.g. collector EM MA GI G2 G3 PA g / t%%%%%

1 AI 200 24 39 1.9 2.8 47

2 A2 200 20 41 1.0 2.6 40

3 A3 (50 wt.) 200 33 40 1.0 1.9 64 bl (50 wt.%)

4 A4 (50% by weight) 200 43 37 1.3 2.4 79 Bl (50% by weight)

5 A5 (50% by weight) 200 34 39 0.8 1.5 65 Bl (50% by weight)

6 A6 (50% by weight) 200 31 40 1.0 1.9 62 Bl (50% by weight)

7 A3 (50% by weight) 100 22 38 1.2 1.7 41 B2 (50% by weight) Contin. Tab. 1: Flotation of Swedish apatite ore in the modified Hallimond tube; Percentages as% by weight

IV. Flotation experiments in the Denver cell

Examples 11 to 18: Comparative Example V5:

Flotation of apatite ore. A low-grade apatite ore with a high proportion of the silicate type of the following composition, based on the main components, was used as the flotation task:

The flotation task had the following grain size distribution:

- 40 μm 20.8% by weight

40 - 100 μm 19.0% by weight

100 - 200 μm 29.1% by weight

200 - 500 μm 26.5% by weight

> 500 μm 4.6% by weight

The collectors according to the invention were used alone and in combination with an alkyl sulfosuccinate Na / NH4 salt (B1) or a technical oleic acid (B3) as co-collectors, the mixture ratio collector: co-collectors 33: 67 to 67: 33 Parts by weight. Technical oleic acid, which was brought into solution with sodium hydroxide solution (B3), served as the reference substance.

In the pre-flotation, a Denver laboratory flotation machine type D1 was floated in the 2-1 cell, the cleaning stages (2 to 4 Post-cleanings) were carried out in a corresponding 1-1 cell. Water of 3 ° d was used as the flotation water; the cloud density during pre-flotation was approx. 500 g / 1. A phenol-formaldehyde condensate (Cl) was used in a dosage of 200 g / t. The pH of the slurry was adjusted to 10 with sodium hydroxide.

The conditioning of the reagents was carried out with stirring at a stirrer speed of 1000 rpm, the conditioning time for pushers and collectors was 5 minutes in each case. The flotation was carried out at a speed of 1100 rpm (2-1 cell) or 1000 rpm (1-1 cell), the flotation time was approximately 4 minutes, during which the flotation foam was removed manually.

In the cleaning flotations, the flotation concentrate of the pre-flotation (rougher concentrate) was added to the 1-1 cell without the addition of reagents and flotated at 1000 rpm for about 4 minutes. Examples 11, 14, 16 and 18 and comparative example V5 were each carried out with four, examples 12 and 15 with three and examples 13 and 17 with two cleaning stages. The results obtained are summarized in Table 3.

Tab. 3: Flotation of minor apatite ore in the Denver cell; Percentages as% by weight

Example collector EM FS MA Gi PA 1 g / t

11 A4 266 rt 83.1 0.54 13 et 5.3 5.42 8 conc 11.6 24.24 79

12 A7 267 rt 83.1 1.55 36 et 10.4 6.34 19 conc 6.5 24.83 45

13 AI (40% by weight) 140 rt 83.9 0.49 12 B3 (60% by weight) et 8.6 5.03 12 conc 7.5 35.74 76

14 A6 (33% by weight) 120 rt 86.8 2.22 55 B3 (67% by weight) et 8.6 6.31 16 conc 4.6 22.32 29

Continued Tab. 3: Flotation of minor apatite ore in the Denver cell; Percentages as% by weight

E.g. collector EM FS MA Gi PA AR g / t%%%%

17 A6 (33 wt%) 120 rt 86.8 2.22 55 B3 (67 wt%) et 8.6 6.31 16 conc 4.6 22.32 29

18 A8 (67 wt%) 132 rt 78.8 0.16 4

Bl (33 wt%) et 8.4 1.15 3 conc 12.8 24.82 93

¥ 5 B3 142 rt 72.8 0.37 8 et 14.6 1.31 5 conc 12.6 24.21 87

Legend: EM = amount used by the collector, based on the ore

FS = flotation level

MA = spread quantity

Gl = P2O5 content

Apply PA = P2θ5 ~

AR = number of cleanings rt = mountains of pre-flotation et = mountains of cleaning level conc = concentrate

Claims

1. A process for the extraction of minerals from non-sulfidic ores by flotation, in which ground ore is mixed with water to form a suspension, air is introduced into the suspension in the presence of a reagent system and the resulting foam is separated off together with the floated solids contained therein, thereby characterized in that salts of esterification products of maleic acid with oligoglycerium partial esters which follow the formula (I) are used as collectors,

R ¹ -0-CH ₂ -CH-CH ₂ -0- [CH ₂ -CH-CH2] _n -0-R ² (I)

I I

0-R ³ 0-R ⁴

in the

Rl, R ² , R ³ and R ⁴ independently of one another are hydrogen, a saturated aliphatic acyl radical having 8 to 18 carbon atoms or a C0-CH = CH-C00X radical, X is an alkali metal or ammonium and n 0 or numbers from 1 to 18

with the proviso that at least one of the substituents R 1 to R ^{4 is} an acly radical and at least one is a C0-CH = CH-C00X radical.

2. The method according to claim 1, characterized in that salts of esterification products of maleic acid with oligoglycerol partial esters are used as collectors, in which n in formula (I) represents numbers from 2 to 5.

3. The method according to any one of claims 1 and 2, characterized gekenn¬ characterized in that salts of esterification products of maleic acid with oligoglycerol partial esters are used as collectors, in which R in formula (I) is a saturated acyl radical having 12 to 18 carbon atoms.

4. The method according to at least one of claims 1 to 3, characterized in that mixtures of

a) salts of esterification products of maleic acid with oligoglycerol partial esters and

b) anionic surfactants selected from the group consisting of fatty acids, alkyl sulfates, alkyl ether sulfates, alkyl sulfosuccinates, alkyl sulfosuccinamates, alkyl benzene sulfonates, alkyl sulfonates, petroleum sulfonates, acyl! actyates, sarcosides, alkyl phosphates and alkyl ether phosphates,

be used.

5. The method according to at least one of claims 1 to 3, characterized in that mixtures of

a) salts of esterification products of maleic acid with oligoglycerol partial esters and b) nonionic surfactants selected from the group consisting of fatty alcohol polyglycol ethers, alkylphenol polyglycol ethers, fatty acid polyglycol esters, fatty acid amidopolyglycol ethers, fatty amine polyglycol ethers, mixed ethers, hydroxy mixed ethers and alkyl glycosides,

be used.

6. The method according to any one of claims 4 and 5, characterized gekenn¬ characterized in that mixtures are used, the proportion of salts of esterification products of maleic acid with oligoglycerol partial esters is 5 to 95 wt .-%.

7. The method according to at least one of claims 1 to 6, characterized in that the collectors are used in quantities of 50 to 2000 g / t crude ore.

8. The method according to at least one of claims 1 to 7, characterized in that salt-type minerals are used as raw ores.