Mineral processing

Abstract

According to the invention there is provided a method of processing a mixture of minerals including the steps of: (a) providing a mixture of minerals which includes a metal containing mineral and one or more unwanted gangue minerals; (b) achieving a contact between the mixture of minerals and polymeric material that includes a mineral binding moiety which selectively binds to the metal containing mineral; and (c) separating the gangue minerals and the polymeric material which has the metal containing mineral bound thereto.

Claims

1. A method of processing a mixture of minerals including the steps of: (a) providing a mixture of minerals which includes a metal containing mineral and one or more unwanted gangue minerals; (b) achieving a contact between the mixture of minerals and polymeric material that includes a mineral binding moiety which selectively binds to the metal containing mineral; and (c) separating the gangue minerals and the polymeric material which has the metal containing mineral bound thereto, wherein the polymeric material includes a polymer formed by polymerising a polymeric precursor which includes a group of sub-formula (I) ##STR00037## where R.sup.1 is i) CR.sup.a, where R.sup.a is hydrogen or alkyl, ii) a group N.sup.+R.sup.13 (Z.sup.m).sub.1/m, S(O).sub.pR.sup.14, or SiR.sup.15 where R.sup.13 is hydrogen, halo, nitro, or hydrocarbyl, optionally substituted or interposed with functional groups, R.sup.14 and R.sup.15 are independently selected from hydrogen or hydrocarbyl, Z is an anion of charge m, p is 0, 1 or 2 and q is 1 or 2, iii) C(O)N, C(S)N, S(O).sub.2N, C(O)ON, CH.sub.2ON, or CHCHR.sup.cN where R.sup.c is an electron withdrawing group, or iv) OC(O)CH, C(O)OCH or S(O).sub.2CH; in which R.sup.12 is selected from hydrogen, halo, nitro, hydrocarbyl, optionally substituted or interposed with functional groups, or R.sup.3R.sup.5Y.sup.1; R.sup.2 and R.sup.3 are independently selected from (CR.sup.7R.sup.8).sub.n, or a group CR.sup.9R.sup.10, CR.sup.7R.sup.8CR.sup.9R.sup.10 or CR.sup.9R.sup.10CR.sup.7R.sup.8 where n is 0, 1 or 2, R.sup.7 and R.sup.8 are independently selected from hydrogen or alkyl, and either one of R.sup.9 or R.sup.10 is hydrogen and the other is an electron withdrawing group, or R.sup.9 and R.sup.10 together form an electron withdrawing group; R.sup.4 and R.sup.5 are independently selected from CH or CR.sup.11 where CR.sup.11 is an electron withdrawing group, the dotted lines indicate the presence or absence of a bond, X.sup.1 is a group CX.sup.2X.sup.3 where the dotted line bond to which it is attached is absent and a group CX.sup.2 where the dotted line to which it is attached is present, Y.sup.1 is a group CY.sup.2Y.sup.3 where the dotted line to which it is attached is absent and a group CY.sup.2 where the dotted line to which it is attached is present, and X.sup.2,X.sup.3,Y.sup.2 and Y.sup.3 are independently selected from hydrogen, fluorine or other substituents.

2. A method of processing a mixture of minerals including the steps of: (a) providing a mixture of minerals which includes a metal containing mineral and one or more unwanted gangue minerals; (b) achieving a contact between the mixture of minerals and polymeric material that includes a mineral binding moiety which selectively binds to the metal containing mineral; and (c) separating the gangue minerals and the polymeric material which has the metal containing mineral bound thereto, wherein the polymeric precursor is a compound of structure [X] ##STR00038## where R.sup.6 is one or more of a bridging group, an optionally substituted hydrocarbyl group, a perhaloalkyl group, a siloxane group, an amide, or a partially polymerised chain containing repeat units, R.sup.22 is O or S, and R.sup.6 includes the mineral binding moiety, or in conjunction with CR.sup.22 forms the mineral binding moiety.

3. A method according to claim 2 in which the mineral binding moiety is a thionocarbamate, thiourea, thiol, thiocycloalkane, thiophosphate or xanthogen formate containing functional group.

4. A method according to claim 3 in which the polymeric precursor is a compound of structure [XI] ##STR00039## where R.sup.6 contains the group NHC(S)O, C(O)NHC(S)O or OC(S)SC(O)O.

5. A method according to claim 4 in which the polymeric precursor is a compound of structure [XII] ##STR00040## where R.sup.20 and R.sup.21 are each independently an alkyl group, optionally substituted or interposed with functional groups, preferably having one to twenty carbon atoms, most preferably having two to twelve carbon atoms, s is 0 or 1, and r is preferably 1 or 2, or a pre-polymer obtained by pre-polymerisation of said compound.

6. A method according to claim 4 in which the polymeric precursor is a compound of structure [XIII] ##STR00041## where R.sup.22 and R.sup.23 are each independently an alkyl group, optionally substituted or interposed with functional groups, preferably interposed with O, and preferably have one to twenty carbon atoms, most preferably two to twelve carbon atoms, and r is preferably 1 or 2, or a pre-polymer obtained by pre-polymerisation of said compound.

7. A method according to claim 2 in which the polymeric precursor is a compound of structure [XIV] ##STR00042## where R.sup.6NH constitutes R.sup.6, and R.sup.6 in combination with NHCS forms the mineral binding moiety.

8. A method according to claim 7 in which the polymeric precursor is a compound of structure [XV] ##STR00043## where R.sup.6OC(O)NH constitutes R.sup.6, and R.sup.6 in combination with OC(O)NHCS forms the mineral binding moiety.

9. A method according to claim 1 in which the polymer formed by polymerising the polymeric precursor encapsulates the mineral binding moiety.

10. A method according to claim 1 in which the polymer formed by polymerising the polymeric precursor is a homopolymer.

11. A method according to claim 1 in which the polymer is a copolymer produced by copolymerising the polymeric precursor with one or more other polymeric precursors and/or with a cross-linker.

12. A method according to claim 1 including the further step of releasing the metal containing mineral from the polymeric material.

13. A method according to claim 1, wherein the polymeric material comprises a polymeric substrate having a surface which has the mineral binding moiety attached thereto.

14. A method according to claim 2 including the further step of releasing the metal containing mineral from the polymeric material.

15. A method according to claim 2, wherein the polymeric material comprises a polymeric substrate having a surface which has the mineral binding moiety attached thereto.

Description

EXAMPLE 1

Attraction of the Copper Sulphide, Chalcopyrite to a Tetraallyl Quaternary Ammonium Polymer Surface Containing the Collector Chemical o,o-Diethyl Thiophosphate

(1) Method

(2) The monomer N,N,N,N-tetraallylpropane-1,3-dimethylammonium p-toluene sulfonate (>99%, 0.965 g) was synthesised in accordance with the method described in Example 7 (synthetic details can also be found in the Applicant's earlier International Publication WO2009/063211), and dissolved in deionised water (0.080 g) using gentle heating and vigorous mixing. The photoinitiator Irgacure 2022 (Ciba SC) (0.0280 g) was then added, followed by the collector chemical potassium O,O-diethyl thiophosphate (Sigma Aldrich, 90%, 0.0285 g) which were thoroughly mixed into the liquid.

(3) A small bead of this mixture was then placed onto a PTFE plate then cured using a FusionUV LH6 high intensity UV lamp with a D-bulb, 100% intensity at 2 m/minute belt speed using a single pass to produce a hard transparent solid.

(4) A sample containing no collector chemical was also made using the same materials and in the same ratio used above but with the omission of O,O-diethyl thiophosphate. This was also cured as a bead of the same size using identical cure conditions.

(5) Two vials each containing approximately 4 g of deionised water and 50 mg of chalcopyrite powder, ground from a larger piece of chalcopyrite crystal using a P100 grade abrasive paper to produce a dark grey powder, were prepared. A polymer bead containing the collector was placed into one vial and a polymer bead containing no collector was placed into the other vial and both vials were sealed and shaken, allowing the chalcopyrite powder to be suspended in the water and then settle evenly on the beads.

(6) The samples were left for 4 hours, after which the beads were extracted and placed into separate beakers of water (200 ml) followed by gentle stirring of the water to remove any loose mineral grains on the surface. The beads were then extracted and placed onto a PTFE plate for examination.

(7) Another reference sample bead containing no collector was also added to deionised water for 4 hours to test for any colour change of the polymer itself in water.

(8) Results

(9) The bead containing the collector chemical O,O-diethyl thiophosphate was darker in appearance than the reference sample without collector and much darker than a polymer bead containing collector that had not been placed into water and chalcopyrite.

(10) The other reference sample bead of the same polymer containing no collector showed no change in appearance when added only to deionised water after 4 hours, suggesting the darkening in colour was attributable to the build up of chalcopyrite on the polymer surface.

(11) ##STR00025##
N,N,N,N-tetraallylpropane-1,3-dimethylammonium p-toluene sulfonate

EXAMPLE 2

Attraction of the Copper Sulphide, Chalcopyrite to a Tetraallyl Quaternary Ammonium Polymer Surface Containing the Collector Chemical o,o-Diethyl Thiophosphate after a Longer Duration of Exposure to Chalcopyrite

(12) Method

(13) Experiment 1 was repeated except that the polymer bead containing the collector and the reference sample without collector were placed in the chalcopyrite and deionised water mixture for 24 hours.

(14) Results

(15) The polymer bead containing the collector was even darker in appearance compared to the one that was left for 4 hours. The difference in appearance between the bead containing the collector and the reference bead no collector was even greater than that after 4 hours duration.

EXAMPLE 3

Removal of Copper Mineral from a Tetraallyl Quaternary Ammonium Polymer Surface Using Ultrasonic Treatment

(16) Method

(17) The monomer N,N,N,N-tetraallylpropane-1,3-dimethylammonium p-toluene sulfonate (>99%, 1.47 g) was dissolved in deionised water (0.28 g) using gentle heating. The collector chemical potassium O,O-diethyl thiophosphate (Sigma Aldrich, 90%, 0.13 g) was dissolved into the mixture, followed by the addition of the photoinitiator Irgacure 2022 (Ciba SC) (approx. 40 mg) with thorough mixing.

(18) Part of the mixture was then placed between two glass slides and cured using a FusionUV LH6 high intensity UV lamp with a D-bulb, 100% intensity at 4 m/minute belt speed with two passes to produce a transparent solid.

(19) A polymer film was then recovered from the microscope slides, which was then placed into a mixture containing approximately 200 mg of each of the following powders: Cu(I) sulphide (325 mesh), Cu(II)sulphide (100 mesh), Cu(I)oxide (<5 microns) and Cu metal powders (10-425 microns) in deionised water (100 ml). The resulting mixture was shaken gently to disperse the minerals, enabling a uniform layer to remain over the polymer film.

(20) After 2 hours the film was removed from the mixture and placed into a beaker of deionised water (200 ml) and gently shaken to remove any loose mineral on the surface. The film was then removed and placed into a beaker containing approximately 100 ml of water and then treated in an ultrasonic bath for a duration of 3 seconds.

(21) Results

(22) Almost all of the copper mineral was seen to instantly detach from the film after the ultrasonic treatment was started.

EXAMPLE 4

Synthesis of O-[4-(diallylamido)-butyl]butylcarbamothioate (a diallylamide monomer containing an alkyl thionocarbamate group)

Preparation of the amido alcohol intermediate, N,N-diallyl-4-hydroxy-butanamide

(23) Gamma butyrolactone (171.0 g, 1.99 mol) and diallylamine (490.0 g, 5.04 mol) were mixed together and heated to 120 C. The mixture was stirred at this temperature for 33 h. A portion (200 g) was stripped, ramping to 110 C. in vacuo (30 mBar), this removed diallylamine but not the gamma butyrolactone.

(24) FTIR (Thin Film): 3420, 3082, 1773, 1630, 1196, 993, 927 cm.sup.1.

(25) From the material stripped at 110 C. in vacuo 70 g was taken up in ethyl acetate (200 ml), dried (MgSO.sub.4), then passed through a plug of silica, flushing through with further ethyl acetate (2200 ml). The solvent was removed in vacuo.

(26) The amido alcohol, containing trace gamma butyrolactone (13.2 g, 0.06 mol) was mixed with water tap water (260 ml) in a flask. To this mixture was added sodium hydroxide (1.4 g, 0.035 mol). The mixture was heated to 70 C. for 16 h. The temperature was increased to reflux and held at this temperature for 2 h. The reaction was allowed to cool to room temperature. Dichloromethane (100 ml) was charged to the flask. The layers were separated. The aqueous was extracted with a dichloromethane (100 ml). The layers were separated and the organics were combined, dried (MgSO.sub.4) and concentrated in vacuo. This gave 6.0 g (45% recovery).

(27) FTIR (Thin Film): 3419, 3083, 1629, 1196, 993, 926 cm.sup.1.

(28) ##STR00026##

N,N-diallyl-4-hydroxy-butanamide

Synthesis of O-[4-(diallylamido)-butyl]butylcarbamothioate

(29) N,N-diallyl-4-hydroxy-butanamide, containing gamma-butyrolactone (15.0 g, 0.07 mol) was charged to a flame dried flask. Butyl isothiocyanate (14.7 g, 0.08 mol) was added dropwise from via a dropping funnel. The mixture was warmed to 60 C. and left stirring at this temperature for 18 h. The mixture was allowed to cool to room temperature. Dibutyl tin dilaurate (0.25 g, 0.4 mmol) was added dropwise. The mixture was heated to 60 C. and left stirring for 64 h. After this time the reaction temperature was increased to 101 C. for 42 h. The mixture was allowed to cool to room temperature. Residual butyl isothiocyanate was stripped from the reaction in vacuo. This gave a brown oil (21.9 g, 92% crude yield).

(30) FTIR (Thin Film): 3326, 3082, 1774, 1716, 16, 1546, 1196, 993, 925 cm.sup.1.

(31) ##STR00027##

EXAMPLE 5

Synthesis of O-[4-(diallylamido)butyl]acetylcarbamothioate (a diallylamide monomer containing a alkylcarbonyl thionocarbamate group)

(32) N,N-diallyl-4-hydroxy-butanamide (5.8 g, 0.03 mol) was charged to a flame dried flask. Acetyl isothiocyanate (3.2 g, 0.03 mol) was added dropwise, under nitrogen. With the aid of a water bath the reaction temperature was maintained below 30 C. The reaction was heated to 30 C. and stirred at this temperature for 18 h. A further portion of N,N-diallyl-4-hydroxy-butanamide (0.5 g, 0.02 mol) was charged and the mixture was stirred for 5 h. The reaction mixture was then heated in vacuo (91 C./30 mBar) over 2.5 h.

(33) A portion of the reaction mixture was removed (2.8 g, 0.01 mol) was dissolved in tetrahydrofuran (25 ml). To this solution was charged sodium hydroxide (0.11 g, 0.003 mol) and warm tap water (25 ml). The mixture was left to stir at ambient temperature overnight. To this mixture was charged dichloromethane (100 ml). The layers were separated and the aqueous layer was further extracted with dichloromethane (250 ml). The combined organics were dried (MgSO.sub.4) taken up in ethyl acetate (50 ml) and passed through a plug of silica. The ethyl acetate was removed in vacuo and the oil was purified by silica flash column chromatography (eluant: 40-60 C. petrol/ethyl acetate 3:1). This gave a yellow oil (0.48 g, 17% recovery, 5.6% overall) that was 95% pure by 1H NMR analysis.

(34) FTIR (Film): 3459, 3082, 1738, 1651, 1546, 1196, 994, 928 cm.sup.1.

(35) .sup.1H NMR (CDCl.sub.3): 1.7 (br, 0.6H), 1.95 (m, 1.9H), 2.05 (s, 2.9H), 2.3 (s, 0.8H), 2.4 (t, 1.9H), 3.85 (d, 2.1H), 3.95 (d, 2.1H), 4.1 (t, 2.0H), 5.15 (m, 4.2H), 5.7 (m, 2.0H) ppm.

(36) ##STR00028##

O-[4-(diallylamido)butyl]acetylcarbamothioate

EXAMPLE 6

Collection of chalcopyrite powder (CuFeS2) onto a polymer film consisting of a copolymer poly(N,N,N,N-tetraallylethanediamide-co-O-[4-(diallylamido)butyl]acetylcarbamothioate)

(37) A mixture of the difunctional monomer N,N,N,N-tetraallylethanediamide and the monofunctional monomer O-[4-(diallylamido)butyl]acetylcarbamothioate) was made in the ratio of 3:1 w/w respectively. The photointiator Irgacure 2022 (Ciba SC) (3 wt %) was then added and mixed thoroughly with gentle warming. This mixture was then deposited as thin film onto a uPVC substrate and then polymerised to a solid copolymer using a high intensity UV lamp (Fe doped mercury bulb, 200 W/cm, 2 passes at 2 metres/minute).

(38) A reference sample was also made containing no thionocarbamate groups in the polymer; a mixture of the monomers N,N,N,N-tetraallylethanediamide and N,N-diallylhexanamide was made in the ratio of 3:1 w/w respectively. N,N-diallylhexanamide was synthesised in accordance with Example 10. The photointiator Irgacure 2022 (Ciba SC) (3 wt %) was then added and mixed thoroughly with gentle warming. This was cured identically to the mixture above containing the thionocarbamate functionalised monomer.

(39) Both samples were cleaned in deionised water and then placed into separate slurries each containing 50 mg of chalcopyrite, ground from a large crystal using a P100 abrasive paper, and 50 ml of deionised water for 18 hours.

(40) Results

(41) Each polymer sample was removed from the slurry. The polymer sample containing O-[4-(diallylamido)butyl]acetylcarbamothioate had attracted more chalcopyrite than the reference sample, demonstrated by its darker appearance, which was then washed off under a stream of water to yield free chalcopyrite powder.

(42) ##STR00029##

N,N,N,N-Tetraallylethanediamide

Synthesis of N,N,N,N-Tetraallylethanediamide

(43) Fresh, dry oxaloyl chloride (ClOOCCOOCl) (200 mmoles) was placed into a 3-necked round bottomed (RB) flask with 200 ml of dry dichloromethane. Freshly distilled diallylamine (400 mmoles) was added to triethylamine (400 mmoles), further diluted (1:1 v/v) in dry dichloromethane then added into a dropping funnel and placed onto the reaction flask. Nitrogen gas was pumped through the vessel through the other two necks. To neutralise HCl produced, the waste gas was bubbled through a CaCO.sub.3 solution. The reaction vessel was then placed into a salt water/ice bath and once the contents were cooled the diallylamine/triethylamine/DCM was added dropwise to the acid chloride solution with continual magnetic stirring of the mixture. The temperature was monitored and maintained between 5-10 C. The dropping of the diallylamine and triethylamine was stopped after three hours and the reaction was left to stir for another hour.

(44) Thin layer chromatography using ethyl acetate and an alumina was used to monitor the reaction comparing starting material to the product. Iodine was used to develop the plate and the reaction product could be seen as a spot that had been eluted much further than the starting material.

(45) To remove the amine chloride and excess diallylamine the reaction liquor was washed in 3M HCl. The monomer stayed in the DCM fraction and was removed using a separating funnel. Two washes of 100 ml HCl were used. The solvent was then removed in a rotary evaporator.

(46) The product was added to dichloromethane (1:1 v/v) and passed through a silica gel (Merck, grade 60 for chromatography) column with dichloromethane as the eluent.

EXAMPLE 7

Synthesis of N,N,N,N-tetraallyl propane dimethylammonium dithiosphosphate (a quaternary ammonium monomer containing a collector group as an anion)

Synthesis of Diamine Intermediate A

(47) 1,3-dibromopropane (99%, 150.0 g, 0.7429 moles), potassium carbonate (97%, 456 g, 3.2996 moles) and 2-propanol (400 ml) were added to an RB reaction flask and brought to reflux with stirring. Diallylamine (99%, 160.5 g, 1.6519 moles), was added to the reaction mixture gradually over an hour and reflux maintained for 120 hours before cooling to room temperature. The mixture was then filtered and the volatiles removed under vacuum. A yellow oil was produced, which was further purified by column chromatography using silica (60 ) and DCM as eluent. After removal of the DCM a pale yellow oil was produced (density=0.86 g/cm.sup.3, yield=80%).

Synthesis of N,N,N,N-tetraallyl propane dimethaminium dithiosphosphate

(48) The diamine intermediate A (6.4 g) was added to anhydrous 2-propanol (200 ml) and stirred at room temperature followed by the addition of o,o-dithiophosphate (9.213 g) over 30 minutes to produce a quaternary ammonium salt (pH=6.5). The 2-propanol was then removed in vacuum to produce the quaternary diallyl ammonium monomer. Yield 95%.

(49) The monomer can be polymerised using the principles described in Example 1.

EXAMPLE 8

Collection of a chalcopyrite rich mineral using a copolymer consisting of poly(N,N-diallyl ethoxycarbonyl thionourea-co-N,N,N,N-tetraallyl ethanediamide)

Synthesis of N,N-diallyl ethoxycarbonyl thionourea (ethyl[di(allyl)carbamothioyl]carbamate)

(50) Ethoxycarbonyl isothiocyanate (98%, 5.00 g) was added dropwise to a mixture of freshly distilled diallylamine (4.0 g) and dichloromethane (50 ml) with continuous stirring for approximately 30 minutes. An exotherm was seen on addition of the isothiocyanate and the temperature was allowed to rise from room temperature to reflux temperature (40 C.). The mixture was left to react for a further 90 minutes after which the mixture was added to ethyl acetate (150 ml) and passed through a short path silica column (6 cm depth) under a partial vacuum. The solution was then filtered and processed in a rotary evaporator to remove any volatiles. Yield=89%

(51) .sup.1H NMR (500 MHz, CDCl.sub.3) /ppm=1.3 (t), 4.2 (q), 4.5 (m), 5.2 (d), 5.85 (m), 7.3 (s)

(52) N,N,N,N-tetraallyl ethanediamide was synthesised in accordance with Example 6.

(53) N,N-diallyl ethoxycarbonyl thionourea and N,N,N,N-tetraallyl ethanediamide crosslinker were added together as a 1:1 (w/w) mixture with the photoinitiator Irgacure 2022 added as 3.5% by weight to the total monomer mixture. This was mixed thoroughly and coated onto a flat piece of poly(carbonate) measuring 10 cm15 cm using a sponge roller until an even coating was made at a weight of approximately 3 gsm. The sample was passed under a focused high intensity UV lamp (FusionUV LH6, D bulb, 100% intensity with 5 passes at 3.5 m/minute).

(54) ##STR00030##

N,N-diallyl ethoxycarbonyl thionourea

(55) The coated panel was placed in a horizontal testing jig that could expose the sample to a slurry over an area of 112 cm.sup.2, 2.0 cm depth. A body of mineral containing chalcopyrite as the major component (42% w/w) with the remainder a mixture of mostly iron sulphides (Pyrrhotite 20% w/w), (Pyrite 16% w/w), was ground in a ball mill to a size fraction of less than 106 m (particle size distribution D10 [5.68 m] D50 [37.29 m], D90 [106.9 m]). 2.0 g of this mineral powder was added to 200 ml of deionised water to make a slurry that was thoroughly dispersed before adding to the test jig that contained the sample panel. The test jig was left stationary for 20 minutes after which the excess mineral was poured away and the mineral adhered to the polymer surface collected using filtration from a mineral concentrate. The mineral collected was thoroughly dried and weighed. This test was repeated several times, with an average taken of the weight collected per unit area of polymer surface compared to a reference polymer that did not contain a thionourea group (see reference sample)

(56) The sample containing the thionourea collector group gave an increase of 32% in weight of mineral collected compared to a reference polymer (Example 10) made with N,N-diallylhexanamide replacing N,N-diallylthionourea.

EXAMPLE 9

Collection of a chalcopyrite rich mineral using a copolymer consisting of poly(2-{2-[2-(2-ethylethoxy xanthogen formate)ethoxy)ethoxy)ethyl-N,N-diallylcarbamate-co-N,N,NN-tetraallyl ethanediamide)

Synthesis of a monomer 2-{2-[2-(2-ethylethoxy xanthogen formate)ethoxy)ethoxy)ethyl-N,N-diallylcarbamate

(57) Triethyleneglycol bischloroformate (97%, Alfa-Aesar, 275.08 g), dry tetrahydrofuran (43.5 g) and triethylamine (101.2 g) were mixed with continuous stirring at 25 C. Diallylamine (97.16 g) was added dropwise to the stirred mixture over 30 minutes so that the exotherm did not rise above 30 C. with the reaction was left to proceed for a further hour. Potassium ethyl xanthogen formate (96%, Aldrich, 160.3 g) was then charged into the reaction mixture over 15 minutes and maintained at 25 C. for 1 hour with continuous stirring. The temperature was raised to 50 C. and maintained for another hour. After cooling, the mixture was filtered then washed with 2100 ml of water. Residual water was removed with anhydrous MgSO.sub.4 before re-filtering after which the sample was further purified by removal of crystalline residues. Solvent was then removed using a rotary evaporator.

(58) .sup.1H NMR (CDCl.sub.3) /ppm=1.1 (t), 1.3 (weak, t), 1.4 (weak, m), 3.3 (m), 3.55 (m), 3.65 (m), 3.75 (m), 4.2 (weak, m), 4.3 (s), 4.7 (s), 5.2 (m), 5.8 (m)

(59) N,N,N,N-tetraallyl ethanediamide was synthesised in accordance with Example 6.

(60) The xanthogen formate containing monomer (2-{2-[2-(2-ethylethoxy xanthogen formate)ethoxy)ethoxy)ethyl-N,N-diallylcarbamate and the crosslinker N,N,N,N-tetraallyl ethanediamide were added together as a 1:1 (w/w) mixture with the photoinitiator Irgacure 2022 added as 3.5% by weight to the total monomer mixture. This was mixed thoroughly and coated onto a flat piece of poly(carbonate) measuring 10 cm15 cm using a sponge roller until an even coating was made at a weight of approximately 3 gsm. The sample was passed under a focused high intensity UV lamp (FusionUV LH6, D bulb, 100% intensity with 5 passes at 3.5 m/minute).

(61) ##STR00031##

2-{2-[2-(2-ethylethoxy xanthogen formate)ethoxy)ethoxy)ethyl-N,N-diallylcarbamate

(62) The coated panel was placed in a horizontal testing jig that could expose the sample to a slurry over an area of 112 cm.sup.2, 2.0 cm depth. A body of mineral containing chalcopyrite as the major component (42% w/w) with the remainder a mixture of mostly iron sulphides (Pyrrhotite 20% w/w), (Pyrite 16% w/w), was ground in a ball mill to a size fraction of less than 106 m (particle size distribution D10 [5.68 m] D50 [37.29 m], D90 [106.9 m]). 2.0 g of this mineral powder was added to 200 ml of deionised water to make a slurry that was thoroughly dispersed before adding to the test jig that contained the sample panel. The test jig was left stationary for 20 minutes after which the excess mineral was poured away and the mineral adhered to the polymer surface collected using filtration from a mineral concentrate. The mineral collected was thoroughly dried and weighed. This test was repeated several times, with an average taken of the weight collected per unit area of polymer surface compared to a reference polymer that replaced the xanthogen formate group with an alkyl group.

(63) The sample containing the xanthogen formate collector group gave an increase of 139% in weight of mineral collected compared to a reference polymer made with N,N-diallylhexanamide (Example 10) instead of the xanthogen formate modified monomer.

EXAMPLE 10

Collection of a chalcopyrite rich mineral using a copolymer consisting of poly(N,N-diallyl hexanamide-co-N,N,N,N-tetraallyl ethanediamide) as a reference

(64) N,N-diallyl hexanamide and N,N,N,N-tetraallyl ethanediamide crosslinker were added together as a 1:1 (w/w) mixture with the photoinitiator Irgacure 2022 added as 3.5% by weight to the total monomer mixture. This was mixed thoroughly and coated onto a flat piece of poly(carbonate) measuring 10 cm15 cm using a sponge roller until an even coating was made at a weight of approximately 3 gsm. The sample was passed under a focused high intensity UV lamp (FusionUV LH6, D bulb, 100% intensity with 4 passes at 3.5 m/minute).

(65) ##STR00032##

N,N-diallylhexanamide

(66) The coated panel was placed in a horizontal testing jig that could expose the sample to a slurry over an area of 112 cm.sup.2, 2.0 cm depth. A body of mineral containing chalcopyrite as the major component (42% w/w) with the remainder a mixture of mostly iron sulphides (Pyrrhotite 20% w/w), (Pyrite 16% w/w), was ground in a ball mill to a size fraction of less than 106 m (particle size distribution D10 [5.68 m] D50 [37.29 m], D90 [106.9 m]). 2.0 g of this mineral powder was added to 200 ml of deionised water to make a slurry that was thoroughly dispersed before adding to the test jig that contained the sample panel. The test jig was left stationary for 20 minutes after which the excess mineral was poured away and the mineral adhered to the polymer surface collected using filtration from a mineral concentrate. The mineral collected was thoroughly dried and weighed. This test was repeated several times, with an average taken of the weight collected per unit area of polymer surface (20.4 g/m.sup.2).

Synthesis of N,N-diallylhexanamide

(67) Diallylamine (99%, 37.0 g), triethylamine (99%, 40.0 g) and dichloromethane (99+%, 50 ml) were mixed and added dropwise to a cooled (0 C.) mixture of hexanoyl chloride (99%+, 50.0 g) in dichloromethane (99+%, 200 ml). Temperature was maintained between 0-10 C. with continuous stirring for several hours to allow all of the diallylamine mixture to be added. The reaction mixture was then left to come to room temperature.

(68) The reaction mixture was then washed in dilute HCl (3 M, 500 ml) and the organic layer separated. Washing of the organic layer was repeated in water or weak brine, followed by drying of the organic layer with anhydrous magnesium sulphate. Dichloromethane and other volatiles were then removed under vacuum to produce a pale yellow liquid, which was then purified further by column chromatography using silica gel (60 ) and dichloromethane as eluent to yield an almost colourless oil. Yield 70%.

(69) .sup.1H NMR (CDCl.sub.3) /ppm: 0.85 (t), 1.25 (m), 1.6 (m), 2.25 (t), 3.8 (d), 3.9 (d), 5.1 (m), 5.7 (m)

EXAMPLE 11

Collection of a chalcopyrite rich mineral using a copolymer consisting of poly(N,N,N,N-tetraallylpropane-1,3-dimethylammonium tosylate-co-N,N-diallylbutane methyl ammonium tosylate) and the collector O,O-diethyl thiophosphate (potassium O,O-diethyl thiophosphate) encapsulated within the polymer

Synthesis of N,N-diallylbutane methylammonium tosylate

(i) Preparation of N,N-diallylbutan-1-amine intermediate

(70) Diallylamine (563.9 g, 5.8 mol) and deionised water (875 ml) were charged to a round bottomed flask equipped with thermometer, condenser and magnetic stirrer bar. Gradually n-butylbromide (194.3 g, 1.4 mol) was added dropwise. The reaction mixture was heated to 60 C. and held at this temperature for 24 h. The reaction was cooled to 40 C. and potassium hydroxide (188 g, 50 wt % solution, 3.3 mol) was charged slowly. Stirring was stopped and the reaction was allowed to settle into layers. The top layer was removed. The lower layer was extracted with dicholoromethane (DCM, 3400 ml). The combined DCM extracts were stripped as a fraction with a second fraction of crude product. The crude product was distilled (T.sub.oil=50 C. to 87 C., 30 mBar) to give a clear oil (165.6 g, 76%).

(71) FTIR (Film): 3078, 1643, 995, 917 cm.sup.1.

(72) .sup.1H NMR (CDCl.sub.3): 0.85 (m, 1.1H, imp), 0.95 (t, 3.2H), 1.25 (m, 2.8H), 1.45 (m, 2.2H), 1.65 (br, 2.2H), 2.4 (m, 2H), 3.1 (d, 4H), 3.25 (m, 0.3H, imp), 5.1 (m, 4.2H), 6.85 (m, 2.1H).

(ii) Preparation of Product

(73) N,N-Diallylbutan-1-amine (162.7 g, 1.06 mol) and toluene (732 ml) were charged to a reactor equipped with mechanical stirrer, thermometer, condenser and nitrogen inlet. The mixture was heated to reflux. Methyl-para-toluene sulfonate (186 g, 1 mol) was gradually charged to the reactor over 1 h 20 minutes. After a further 2 h refluxing the mixture was cooled to ambient temperature. The reaction mixture was charged to a separating funnel and the crude product layer was run off. The crude product is gradually stripped in vacuo (30 mBar), gradually increasing the oil bath temperature to 150 C. The crude product is held under these conditions for 3.5 h then cooled to ambient under a nitrogen purge. A viscous golden brown oil is obtained (293 g, 86%).

(74) FTIR (Film): 3700-3100 (br), 3088, 3029, 2964, 2875, 1644, 1478, 1215, 1191, 1122, 1035, 1012, 683 cm.sup.1.

(75) .sup.1H NMR (CDCl.sub.3): 0.85 (t, 2.7H), 1.25 (m, 1.8H), 1.65 (m, 1.8H), 2.3 (s, 3.1H), 2.45 (br, 0.9H), 2.9 (m, 0.2H, imp), 3.1 (2s, 3H), 3.2 (m, 1.6H), 3.65 (m, 0.4H, imp), 4.0 (m, 3.3H), 4.05 (m, 0.3H), 5.45 (m, 0.4H), 5.6 (2d, 3.6H), 5.85 (m, 1.7H), 6.0 (m, 0.3H), 7.1 (t, 2H), 7.75 (t, 2H), 10.15 (m, 0.07H, imp).

(76) ##STR00033##

N,N-diallylbutane methylammonium tosylate

(77) The monomer N,N,N,N-tetraallylpropane-1,3-dimethylammonium tosylate was synthesised in accordance with the method described in Example 7. Synthetic details can also be found in the Applicant's earlier International Publication WO2009/063211.

(78) A mixture containing the monomers N,N,N,N-tetraallylpropane-1,3-dimethylammonium tosylate (14.037 g) and N,N-diallylbutane methyl ammonium tosylate (21.070 g) with potassium O,O-diethyl thiophosphate (0.848 g), deionised water (0.889 g) was heated to 80 C. for several hours with ultrasonic treatment to help dissolve potassium O,O-diethyl thiophosphate. The sample was cooled and the photo-initiator Irgacure 2022 added (0.732 g) with the sample again heated and mixed in similar way to produce a viscous liquid that was applied onto a polycarbonate panel (10 cm15 cm, 2 mm thick) as uniform layer 1-2 mm thick over an 8 cm8 cm area. This was cured by passing under a high intensity UV lamp 3 times at 2.0 m/minute (Fusion UV LH6, D bulb, 100% power) to produce a solid film.

(79) The coated panel was placed in a horizontal testing jig, that could contain a slurry in a volume of dimensions 8 cm8 cm area, 1.0 cm depth. A body of mineral containing chalcopyrite as the major component (42% w/w) with the remainder a mixture of mostly iron sulphides (Pyrrhotite 20% w/w), (Pyrite 16% w/w), was ground in a ball mill to a size fraction of less than 106 m (particle size distribution D10 [5.68 m] D50 [37.29 m], D90 [106.9 m]). 0.3 g of this mineral powder was added to 30 ml of deionised water to make a slurry that was thoroughly dispersed before adding to the test jig that contained the sample panel. The test jig was left stationary for 20 minutes after which the excess mineral was poured away and the mineral adhered to the polymer surface collected using filtration from a mineral concentrate. The mineral collected was thoroughly dried and weighed. This test was repeated several times, with an average taken of the weight collected per unit area of polymer surface compared to a reference polymer that did not contain any potassium O,O-diethyl thiophosphate

(80) Reference Polymer

(81) A sample was made identically to the above sample panel, apart from no potassium O,O-diethyl thiophosphate being added. This panel was also tested identically to samples with the potassium O,O-diethyl thiophosphate.

(82) The sample containing the collector material potassium O,O-diethyl thiophosphate collector gave an increase of 24% in weight of mineral collected compared to the reference polymer.

EXAMPLE 12

Collection of chalcopyrite rich mineral using a copolymer consisting of poly(N,N,N,N-Tetraallylpropane-1,3-dimethylammonium tosylate-co-N,N-diallylbutane methyl ammonium tosylate-co-1,1-diallyl piperidinium O,O-diethyl thiophosphate)

Synthesis of 1,1-diallyl piperidinium O,O-diethyl thiophosphate

(i) Synthesis of N,N-diallylpiperidine bromide intermediate

(83) A mixture of potassium carbonate (103.66 g), isopropanol (78.50 g) and allyl bromide (133.08 g) were charged into a flask and left stirring at room temperature. Piperidine (42.58 g) was added dropwise over 1 hour with constant stirring with an instant exotherm observed. Temperature was maintained below 50 C. with occasional rises to 60 C. seen straight after addition of piperidine. The reaction was then brought to reflux and held for 24 hours with constant stirring. The mixture was then left to cool to approximately 50 C. for work up. The warm reaction mixture was filtered to remove potassium carbonate and precipitated salts formed during the reaction. The solids were washed in dichloromethane to remove residual product and added to the filtered reaction product. Rotary evaporation was used to remove solvent and volatiles until a soft, amber coloured solid remained. Toluene was then added (300 ml) to wash the product, which was then filtered under vacuum followed by rewashing with toluene until the toluene liquid fraction was clear. Washing with acetone was performed to yield an off-white powder that was then dried at 60 C.

(84) Yield 60.4%

(85) .sup.1H NMR (CDCl.sub.3) : 1.8 (m), 1.9 (m), 3.7 (m), 4.25 (m), 5.75 (m), 5.95 (m)

(ii) Preparation of Product

(86) O,O-Diethyl thiophosphate potassium salt (10.0 g, 0.048 mol) and methanol (150 ml) were charged to a flame dried flask. In a separate flame dried flask 1,1-diallylpiperidinium bromide (11.8 g, 0.048 mol) was dissolved in methanol (30 ml), this solution was charged to the first flask, washing in with methanol (20 ml). The reaction mixture was heated to reflux and held at this temperature for 24 h and then cooled to room temperature. The solvent was removed in vacuo. The residual slurry was dissolved in chloroform (60 ml) and solids were removed by decanting the chloroform solution. Further chloroform was added (20 ml). The chloroform solution was washed with deionised water (5 ml). The layers were separated and the chloroform layer was washed with further deionised water (5 ml). The chloroform was removed in vacuo to give a clear yellow oil (14.4 g, 89%).

(87) FTIR (Film): 3406, 3085, 1642, 1469, 1165, 1042, 937 cm.sup.1.

(88) .sup.1H NMR (CDCl.sub.3) : 1.2 (t, 5.8H), 1.75 (m, 2H), 2.7 (br, 1.7H, imp), 3.6 (t, 4H), 3.95 (m, 3.8H), 4.1 (t, 4.0H), 5.65 (d, 2H), 5.75 (d, 2.0H) 5.95 (m, 2H) ppm.

(89) The syntheses of N,N,N,N-Tetraallylpropane-1,3-dimethylammonium tosylate and N,N-diallylbutane methyl ammonium tosylate are described in Example 11.

(90) N,N,N,N-Tetraallylpropane-1,3-dimethylammonium tosylate (5.00 g) was heated until molten and mixed with N,N-diallylbutane methyl ammonium tosylate (2.50 g) and reheated to 80 C. with periodic mixing in an ultrasonic bath. 1,1-diallyl piperidinium O,O-diethyl thiophosphate (2.50 g) was then added to the mixture, which was maintained at 80 C. for one hour until fully dissolved and dispersed with periodic treatment in an ultrasonic bath. Irgacure 2022 was then added at 2% by weight of total monomers to produce a viscous liquid that was applied onto a polycarbonate panel (10 cm15 cm, 2 mm thick) as uniform layer 1-2 mm thick over an 8 cm8 cm area. This was cured by passing under a high intensity UV lamp 2 times at 3.0 m/minute (Fusion UV LH6, D bulb, 100% power) to produce a solid film.

(91) The coated panel was placed in a horizontal testing jig, that could contain a slurry in a volume of dimensions 8 cm8 cm area, 1.0 cm depth. A body of mineral containing chalcopyrite as the major component (42% w/w) with the remainder a mixture of other minerals that included mainly iron sulphides (Pyrrhotite 20% w/w), (Pyrite 16% w/w), was ground in a ball mill to a size fraction of less than 106 m. (Distribution D10 [5.68 m] D50 [37.29 m], D90 [106.9 m])). 0.3 g of this mineral powder was added to 30 ml of deionised water to make a slurry that was thoroughly dispersed before adding to the test jig that contained the sample panel. The test jig was left still for 20 minutes after which the excess mineral was poured away and the mineral adhered to the polymer surface collected using filtration from a concentrate of the collected mineral in water. The mineral collected was thoroughly dried and weighed. This test was repeated several times, with an average taken of the weight collected per unit area of polymer surface compared to a reference polymer that did not contain any O,O-diethyl thiophosphate.

(92) Reference Panel

(93) A sample was made in an identical way to the polymer containing the thiophosphate unit but with all of the 1,1-diallyl piperidinium O,O-diethyl thiophosphate replaced with N,N-diallylbutane methylammonium tosylate to make a poly(N,N,N,N-Tetraallylpropane-1,3-dimethylammonium tosylate-co-N,N-diallylbutane methyl ammonium tosylate) copolymer. This panel was also tested identically to samples with the O,O-diethyl thiophoshphate.

(94) The sample containing the collector material O,O-diethyl thiophosphate collector gave an increase of 14% increase in weight of mineral collected compared to the reference polymer.

EXAMPLE 13

Collection of a Chalcopyrite Rich Mineral Using a Polymer Surface Consisting of Functionalised Poly(Ethyleneimine) Grafted onto a Poly(Glycidyl Methacrylate-Co-Ethyleneglycol Dimethacrylate) Surface

(95) A nylon 6,6 panel (dimensions 10 cm15 cm) was coated with a thin layer a 2-3 microns thick of a mixture consisting of glycidyl methacrylate (97%, Aldrich, 0.81 g), ethyleneglycol dimethacrylate crosslinker (98%, Alfa Aesar, 0.20 g) and the photoinitiator Irgacure 2022 (0.025 g). This was cured using a high intensity UV lamp (FusionUV LH6, D bulb, 100% intensity with 6 passes at 3.5 m/minute).

(96) Poly(ethylene imine) (PEI, branched, 10,000 molecular weight, 99%, Alfa Aesar) was applied neat as a thin, even coating over the methacrylate coating and then left at 80 C. for 1 hour. After this the excess PEI was removed by washing water and then 2-propanol with gentle wiping of the surface to help remove any residues. After drying a hard surface was retained but was far more hydrophilic than the methacrylate coating with FT-IR spectroscopy showing spectral changes consistent with the addition of PEI.

(97) To convert available amine groups present on the attached PEI chains to thionourea collector groups an even coating of ethoxy carbonyl isothiocyanate (ECITC) was then spread over the panel and left at room temperature for 45 minutes. Excess ECITC was wiped off the surface and the surface was then cleaned thoroughly in 2-propanol and dried.

(98) The coated panel was placed in a horizontal testing jig that could expose the sample to a slurry over an area of 112 cm.sup.2, 2.0 cm depth. A body of mineral containing chalcopyrite as the major component (42% w/w) with the remainder a mixture of mostly iron sulphides (Pyrrhotite 20% w/w), (Pyrite 16% w/w), was ground in a ball mill to a size fraction of less than 106 m (particle size distribution D10 [5.68 m] D50 [37.29 m], D90 [106.9 m]). 2.0 g of this mineral powder was added to 200 ml of deionised water to make a slurry that was thoroughly dispersed before adding to the test jig that contained the sample panel. The test jig was left stationary for 20 minutes after which the excess mineral was poured away and the mineral adhered to the polymer surface collected using filtration from a mineral concentrate. The mineral collected was thoroughly dried and weighed. This test was repeated several times, with an average taken of the weight of collected mineral per unit area of polymer surface and gave an increase of approximately 110% in weight of mineral collected compared to a reference polymer made with poly(N,N-diallylhexanamide-co-N,N,N,N-tetraallylethanediamide).

EXAMPLE 14

Collection of a chalcopyrite rich mineral using a thiocarbamate functionalised methacrylate polymer poly(O-ethyl O-(3-methyl-2-oxobut-3-en-1-yl)imidothiodicarbonate)

(99) 2-Hydroxy ethyl methacrylate (Aldrich, 14.9 g, 0.114 mol) and THF (28 g) were charged to a round bottomed flask equipped with magnetic stirrer bar, condenser and nitrogen inlet. 4-Methoxyphenol (0.23 g, 0.0019 mol) was charged to flask. Ethoxycarbonyl isothiocyanate (Alfa Aesar, 97%15.5 g, 0.118 mol) was gradually charged to the flask. The reaction mixture was heated at 62 C. for 16 h then refluxed for 3 h. A further portion of 2-hydroxy ethyl methacrylate (0.5 g g, 0.004 mol) was charged and reflux was maintained for 4 h.

(100) A portion of the reaction mixture (14.4 g) was treated with water (80 ml) and sodium hydroxide (0.07 g, 1.75 mmol) at 60 C. for 4 h. DCM (160 ml) was added to the reaction mixture, the layers were then separated and the aqueous layer was further extracted with DCM (160 ml). The DCM solution was dried (MgSO.sub.4), filtered and stripped. This gave 6.6 g of an oil (21%). The remaining reaction mixture (44.5 g) was treated in a similar manner with water (247 ml) and sodium hydroxide (0.2 g). The reaction mixture was extracted with DCM (2250 ml), dried (MgSO.sub.4) and stripped. Toluene (250 ml) was added to the stripped oil and stripped this gave the monomer O-ethyl 0-(3-methyl-2-oxobut-3-en-1-yl)imidothiodicarbonate as an oil (23.6 g, overall 30.2 g, 98%).

(101) ##STR00034##

O-ethyl 0-(3-methyl-2-oxobut-3-en-1-yl)imidothiodicarbonate

(102) FTIR (Film): 3517, 3259, 2982, 1770, 1720, 1636, 1521, 1251, 1232, 1171, 1097, 948, 769 cm.sup.1.

(103) .sup.1H NMR (CDCl.sub.3): 1.25 (t, 3.1H), 1.95 (s, 3H), 4.2 (q, 1.9H), 5.15 (m, 4.2H), 4.3 (m, 0.3H, imp), 4.45 (t, 2.2H), 2.25 (t, 1.9H), 5.1 (s, 1H), 6.15 (s, 1H), 8.25 (br, 0.9H).

(104) MS (CH.sub.2Cl.sub.2): C.sub.10H.sub.15NO.sub.5S requires 261.0671. found 261.0666.

(105) A mixture containing this thiocarbamate functionalised methacrylate monomer (0.747 g), ethyleneglycol dimethacrylate (Alfa-Aesar, 0.752 g) and the photo-intiator Irgacure 2022 (0.039 g) was deposited as a thin film, of several grams per square metre coating weight, onto several polycarbonate panels (10 cm20 cm2 mm thickness) using a soft roller. The coated panel was placed in a horizontal testing jig that could expose the sample to a slurry over an area of 15 cm.sup.2, 2.0 cm depth. A body of mineral containing chalcopyrite as the major component (42% w/w) with the remainder a mixture of mostly iron sulphides (Pyrrhotite 20% w/w), (Pyrite 16% w/w), was ground in a ball mill to a size fraction of less than 106 m (particle size distribution D10 [5.68 m], D50 [37.29 m], D90 [106.9 m], D3,2 [12.36 m], D4,3 [46.75 m]). 2.0 g of this mineral powder was added to 200 ml of deionised water to make a slurry that was thoroughly dispersed before adding to the test jig that contained the sample panel. The test jig was left stationary for 20 minutes after which the excess mineral was poured away and the mineral adhered to the polymer surface collected using filtration from a mineral concentrate. The mineral collected was thoroughly dried and weighed. This test was repeated several times, with an average taken of the weight collected per unit area of polymer surface compared to a reference polymer that did not contain a thiocarbamate group

(106) The sample containing the thiocarbamate collector group collected 4.18 mg/cm.sup.2 (an increase of 101% in weight of mineral collected compared to a reference polymer made with N,N-diallylhexanamide and N,N-tetraallylethanediamide).

EXAMPLE 15

Collection of a chalcopyrite rich mineral using a functionalised silane polymer poly(ethyl {[3-(triethoxysilane)propyl]carbamothioyl}carbamate) made by sol-gel process

Synthesis of ethyl {[3-(triethoxysilane)propyl]carbamathioyl}carbamate) monomer

(107) (3-Aminopropyl)triethoxysilane (Sigma-Aldrich, >98%, 23.9 g, 0.108 mol) was charged to a flame dried round bottomed flask equipped with magnetic stirrer bar, condenser and nitrogen inlet. 4-Methoxyphenol (0.23 g, 0.0019 mol) was charged to flask. Ethoxycarbonyl isothiocyanate (Alfa Aesar, >97%, 13.8 g, 0.105 mol) was gradually charged to the flask. The reaction mixture was heated at 45-60 C. for 5 h. This gave a clear yellow oil product (32.8 g, 87%) which 94% pure by NMR analysis.

(108) FTIR (Film): 3289, 2975, 2927, 2885, 1713, 1547, 1245, 1097, 994, 948, 768 cm.sup.1.

(109) .sup.1H NMR (CDCl.sub.3): 0.15 (m, 2H), 1.2 (t, 9H), 1.3 (t, 2.8H), 1.5 (m, 0.1H, sm), 1.75 (quin, 1.9H), 2.7 (m, 0.1H, sm), 3.65 (t, 1.8H), 3.7 (q, 0.3H, sm), 3.8 (q, 5.7H), 4.2 (q, 1.9H), 9.7 (br, 0.9H).

(110) Ethyl {[3-(triethoxysilane)propyl]carbamothioyl}carbamate (0.76 g), acetic acid (pH3.0) (1.01 g) and isopropanol (2.0 g) were mixed together and heated to 50 C. in an oil bath for 6 hours with constant stirring. The solution was cooled to room temperature and left for 24 hours. The mixture was then spread over a 2 mm thick 10 cm20 cm poly(carbonate) plaque as a 1 mm layer over the whole surface. This was placed into a flat-based glass container, sealed by placing a glass lid on top and placed into an oven at 50 C. for a further 6 hours. The sample was then cooled and left at ambient for a further 18 hours with the lid partially open. The sample was reheated to 50 C. still within the partially opened chamber for a further 6 hours and then left to cool to ambient and stored at this temperature for 5 days. The sample was then placed in a glass container with no lid for a further 3 hours at 50 C. and left to cool to produce a hard clear coating.

(111) ##STR00035##

ethyl {[3-(triethoxysilane)propyl]carbamothioyl}carbamate

(112) The coated panel was placed in a horizontal testing jig that could expose the sample to a slurry over an area of 15 cm.sup.2, 2.0 cm depth. A body of mineral containing chalcopyrite as the major component (42% w/w) with the remainder a mixture of mostly iron sulphides (Pyrrhotite 20% w/w), (Pyrite 16% w/w), was ground in a ball mill to a size fraction of less than 106 m (particle size distribution D10 [5.68 m] D50 [37.29 m], D90 [106.9 m]). 2.0 g of this mineral powder was added to 200 ml of deionised water to make a slurry that was thoroughly dispersed before adding to the test jig that contained the sample panel. The test jig was left stationary for 20 minutes after which the excess mineral was poured away and the mineral adhered to the polymer surface collected using filtration from a mineral concentrate. The mineral collected was thoroughly dried and weighed. This test was repeated several times, with an average taken of the weight collected per unit area of polymer surface compared to a reference polymer that did not contain a thionourea group (see reference sample)

(113) The sample containing the thionourea collector group gave an increase of over twice weight of mineral collected compared to a reference polymer made with N,N-diallylhexanamide replacing N,N,N,N-tetraallylethanediamide.

EXAMPLE 16

Collection of cobalt sulphide (CoS) using a copolymer consisting of poly(N,N-diallyl ethoxycarbonyl thionourea-co-N,N,N,N-tetraallyl ethanediamide)

(114) A coated panel was prepared and placed in a horizontal testing jig in accordance with Example 8. 2.0 g of cobalt sulfide (CoS) with an average particle size of 150 m (100 mesh) was added to 200 ml of deionised water to make a slurry that was thoroughly dispersed before adding to the test jig that contained the sample panel. The test jig was left stationary for 20 minutes after which the excess mineral was poured away and the mineral adhered to the polymer surface collected using filtration from a mineral concentrate. The mineral collected was thoroughly dried and weighed. This test was repeated several times, with an average taken of the weight collected per unit area of polymer surface. This was compared to cobalt disulphide collected from a reference polymer that was made using the same method and test conditions but with N,N-diallylhexanamide used to replace the N,N-diallylthionourea monomer.

(115) The sample containing the thionourea collector group gave an increase of 65% in weight of the cobalt sulfide collected compared to the reference polymer.

EXAMPLE 17

Collection of iron disulphide mineral (pyrite) using a xanthogen formate containing copolymer, poly((2-(2-(2-(2-ethylethoxy xanthogen formate)ethoxy)ethoxy)ethyl-N,N-diallylcarbamate-co-N,N,NN-tetraallyl ethanediamide)

(116) A coated panel was prepared and placed in a horizontal testing jig in accordance with Example 9. 2.0 g of iron disulphide of particle size less than 106 m was added to 200 ml of deionised water to make a slurry that was thoroughly dispersed before adding to the test jig that contained the sample panel. The test jig was left stationary for 20 minutes after which the excess mineral was poured away and the mineral adhered to the polymer surface collected using filtration from a mineral concentrate. The mineral collected was thoroughly dried and weighed. The sample showed a collection of 1.85 mg/cm.sup.2 of iron pyrite.

EXAMPLE 18

Collection of Chalcopyrite Mineral Using Chalcopyrite Pre-teated with an Amine Functionalised Thionocarbamate Collector with Subsequent Reaction to a Cellulose Surface Modified with Tosyl Ester Functionality

(117) Description

(118) This experiment utilises a solid surface with a different functional chemistry to combine with a chalcopyrite particle pre-treated with a reactive, functionalised collector. The mechanism then consists of: (1) Attachment of collector to chalcopyrite in solution (as in froth flotation) (2) Attachment of collector present on chalcopyrite to an active group on the collecting solid surface
This scheme uses a collector that contains a thionocarbamate on one end of the collector molecule to bond to chalcopyrite with an amine on the other end to bond to a tosyl ester group on a modified cellulose surface. Treatment of chalcopyrite with the collector was performed separately to the attachment of the mineral to the solid surface.
Experiment
Preparation of the Collector Molecule

(119) Ethoxycarbonyl isothiocyanate (5.01 g) in dichloromethane (10 ml) was charged into 50 ml 3-necked flask and cooled to 10 C. 2-dimethylaminoethanol (3.68 g) in dichloromethane (10 ml) was added drop-wise with stirring over 10 minutes. The reaction was then allowed to reach room temperature, after which more dichloromethane was added (30 ml) with stirring maintained for a further 2 hours. Volatiles were then removed using a rotary evaporator to yield a thick yellow oil. Yield >90%.

(120) ##STR00036##

(121) .sup.1H NMR (500 MHz, CDCl.sub.3) /ppm=1.3 (t), 2.85 (s), 2.95 (s), 3.4 (t), 4.2 (q), 4.5 (t)

(122) Preparation of the Chalcopyrite with Collector

(123) A ground chalcopyrite sample (approx. 20 g, 16% Cu, <106 m) was introduced to a dilute solution of and the above amine functionalised collector molecule (0.3 g) in deionised water (200 ml). The mixture was heated to approximately 40 C. and then gently stirred for 30 minutes. The chalcopyrite was filtered and then washed 4 times by removing the chalcopyrite and reintroducing to 200 ml of water with stirring for each cleaning step. The treated chalcopyrite was then dried at 60 C. to produce a green powder, similar in appearance to the mineral initially used.

(124) Preparation of the Modified Cellulose Surface to Collect Chalcopyrite/Collector

(125) A mixture of toluene (100 ml), pyridine (15 ml) and tosyl chloride (0.5 g) was heated to approximately 80 C. in a flat bottomed glass tank. A cellulose filter paper (Whatman no. 2, approx. 8 cm dia.) was dried then introduced to the mixture and the tank then sealed. The paper was left for 45 minutes with periodic gentle mixing of the solution.

(126) The paper was then retrieved, washed in toluene and then acetone thoroughly to remove all residues. The sample was then dried at 55 C. for 30 minutes.

(127) Treatment of the Modified Cellulose with the Chalcopyrite/Collector

(128) The treated cellulose filter paper was then introduced to a slurry containing 2.0 g of treated chalcopyrite in 200 ml of water was introduced to a 2 litre glass beaker with the slurry kept in suspension during addition of the paper. The paper was placed at the bottom of the beaker with the suspension allowed to settle onto the paper. The mixture was then heated to 70-80 C. for one hour after which the paper was gently extracted from the mixture so that a thin layer of mineral remained attached to the surface.

(129) The chalcopyrite that remained on the filter paper was removed by washing the chalcopyrite off the paper in water and re-filtration of the chalcopyrite, which was then thoroughly dried and analysed by XRF.

(130) This experiment was repeated but with slightly more mineral left on the paper after extraction.

(131) Results

(132) XRF analysis showed an average of 18.03% Cu present in the extracted mineral from the modified cellulose. When the experiment was repeated with a slightly thicker layer of collected mineral a value of 17.33% Cu was attained. This was significantly greater than the copper concentration of 16.16% present in the original mineral feedstock.

EXAMPLE 19

Reference Experiment for Collection of Chalcopyrite Mineral Using Chalcopyrite Pre-Treated with an Amine Functionalised Thionocarbamate Collector onto a Cellulose Surface

(133) Description

(134) This experiment provides a reference test for the collection of chalcopyrite onto a modified cellulose surface. The experiment was identical to the one that utilises an amine functionalised thionocarbamate collector group except that the cellulose surface was not treated to contain tosyl ester.

(135) Results

(136) XRF analysis showed an average of 15.94% copper present in the extracted mineral from the unmodified cellulose paper. This was similar to the copper concentration of 16.17% present in the original mineral feedstock.

EXAMPLE 20

Collection of chalcopyrite from a mixture of separately ground chalcopyrite and ore body using a copolymer consisting of poly(N,N-diallyl ethoxycarbonyl thionourea-co-N,N,N,N-tetraallyl ethanediamide)

(137) A coated panel was prepared and placed in a horizontal testing jig in accordance with Example 8. A mineral used for the slurry comprised of a mixture of chalcopyrite (>80% by weight) with a ground ore body that comprised mostly of silicates with approximately 1% chalcopyrite by weight in a ratio of 60:40 chalcopyrite:ore body respectively (particle size distribution D10 [5.93 m], D50 [33.06 m], D90 [104 m] D3,2 [15.89 m], D4,3 [44.55 m]). 2.0 g of this mineral powder was added to 200 ml of deionised water to make a slurry that was thoroughly dispersed before adding to the test jig that contained the sample panel. The test jig was left stationary for 20 minutes after which the excess mineral was poured away and the mineral adhered to the polymer surface collected using filtration from a mineral concentrate. The mineral collected was thoroughly dried and weighed. This test was repeated several times, with an average taken of the weight collected per unit area of polymer surface.

(138) The mineral collected from the thionourea containing polymer group showed an increase in copper level of 12.7% using X-Ray fluorescence spectroscopy compared to the original mineral feedstock with a particle size distribution D10 [8.04 m], D50 [45.03 m], D90 [112.53 m], D3,2 [20.45 m], D4,3 [53.51 m].

EXAMPLE 21

Collection of chalcopyrite from a mixture of separately ground chalcopyrite and ore body using a copolymer consisting of poly(2-(2-(2-(2-ethylethoxy xanthogen formate)ethoxy)ethoxy)ethyl-N,N-diallylcarbamate-co-N,N,N,N-tetraallyl ethanediamide)

(139) A coated panel was prepared and placed in a horizontal testing jig in accordance with Example 9. A mineral used for the slurry comprised of a mixture of chalcopyrite (approx. 80% purity) with a ground ore body that comprised mostly of silicates (only 1% chalcopyrite by weight) in a ratio of 60:40 ratio of chalcopyrite:ore body respectively (particle size distribution D10 [5.61 m] D50 [26.68 m], D90 [96.38 m], D3,2 [14.82 m], D4,3 [46.83 m]). 2.0 g of this mineral powder was added to 200 ml of deionised water to make a slurry that was thoroughly dispersed before adding to the test jig that contained the sample panel. The test jig was left stationary for 20 minutes after which the excess mineral was poured away and the mineral adhered to the polymer surface collected using filtration from a mineral concentrate. The mineral collected was thoroughly dried and weighed. This test was repeated several times, with an average taken of the weight collected per unit area of polymer surface.

(140) The mineral collected from the polymer containing the xanthogen formate group showed an increase in copper level of 16.5% using X-Ray fluorescence spectroscopy compared to the original mineral feedstock with a particle size distribution of D10 [8.52 m] D50 [46.50 m], D90 [112.69 m], D3,2 [21.36 m], D4,3 [54.58 m].