WO2023214425A1 - A selective and efficient process for the extraction of noble metal ions from complex mixtures - Google Patents
A selective and efficient process for the extraction of noble metal ions from complex mixtures Download PDFInfo
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- WO2023214425A1 WO2023214425A1 PCT/IN2023/050401 IN2023050401W WO2023214425A1 WO 2023214425 A1 WO2023214425 A1 WO 2023214425A1 IN 2023050401 W IN2023050401 W IN 2023050401W WO 2023214425 A1 WO2023214425 A1 WO 2023214425A1
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- WIPO (PCT)
- Prior art keywords
- extraction
- niacin
- noble metal
- selective
- ions
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- 229910000510 noble metal Inorganic materials 0.000 title claims abstract description 50
- 238000000605 extraction Methods 0.000 title claims abstract description 46
- 238000000034 method Methods 0.000 title claims abstract description 46
- 239000000203 mixture Substances 0.000 title claims abstract description 24
- 150000002500 ions Chemical class 0.000 title claims abstract description 23
- 230000008569 process Effects 0.000 title claims description 27
- 239000010931 gold Substances 0.000 claims abstract description 45
- 239000004793 Polystyrene Substances 0.000 claims abstract description 27
- 229910052737 gold Inorganic materials 0.000 claims abstract description 20
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims abstract description 16
- 229920002223 polystyrene Polymers 0.000 claims abstract description 13
- 239000002131 composite material Substances 0.000 claims description 30
- 229910052751 metal Inorganic materials 0.000 claims description 27
- 239000002184 metal Substances 0.000 claims description 27
- 239000011664 nicotinic acid Substances 0.000 claims description 20
- 229960003512 nicotinic acid Drugs 0.000 claims description 20
- 238000001179 sorption measurement Methods 0.000 claims description 18
- 239000000463 material Substances 0.000 claims description 12
- PVNIIMVLHYAWGP-UHFFFAOYSA-N Niacin Chemical compound OC(=O)C1=CC=CN=C1 PVNIIMVLHYAWGP-UHFFFAOYSA-N 0.000 claims description 11
- 235000001968 nicotinic acid Nutrition 0.000 claims description 11
- 239000003463 adsorbent Substances 0.000 claims description 9
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical group C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 claims description 6
- 150000002739 metals Chemical class 0.000 claims description 6
- 238000005065 mining Methods 0.000 claims description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 4
- 239000002033 PVDF binder Substances 0.000 claims description 4
- 239000004372 Polyvinyl alcohol Substances 0.000 claims description 4
- 238000005516 engineering process Methods 0.000 claims description 4
- 238000001914 filtration Methods 0.000 claims description 4
- 229920002401 polyacrylamide Polymers 0.000 claims description 4
- 229920002239 polyacrylonitrile Polymers 0.000 claims description 4
- 229920000767 polyaniline Polymers 0.000 claims description 4
- 229920002451 polyvinyl alcohol Polymers 0.000 claims description 4
- 229920002981 polyvinylidene fluoride Polymers 0.000 claims description 4
- 239000010793 electronic waste Substances 0.000 claims description 3
- 229920002492 poly(sulfone) Polymers 0.000 claims description 3
- 229920000642 polymer Polymers 0.000 claims description 3
- 229920006395 saturated elastomer Polymers 0.000 claims description 3
- 239000002699 waste material Substances 0.000 claims description 3
- 229920001661 Chitosan Polymers 0.000 claims description 2
- 229910002567 K2S2O8 Inorganic materials 0.000 claims description 2
- DBMJMQXJHONAFJ-UHFFFAOYSA-M Sodium laurylsulphate Chemical compound [Na+].CCCCCCCCCCCCOS([O-])(=O)=O DBMJMQXJHONAFJ-UHFFFAOYSA-M 0.000 claims description 2
- 229920002125 Sokalan® Polymers 0.000 claims description 2
- 239000001913 cellulose Substances 0.000 claims description 2
- 229920002678 cellulose Polymers 0.000 claims description 2
- 238000011065 in-situ storage Methods 0.000 claims description 2
- 238000006116 polymerization reaction Methods 0.000 claims description 2
- USHAGKDGDHPEEY-UHFFFAOYSA-L potassium persulfate Chemical compound [K+].[K+].[O-]S(=O)(=O)OOS([O-])(=O)=O USHAGKDGDHPEEY-UHFFFAOYSA-L 0.000 claims description 2
- 235000019394 potassium persulphate Nutrition 0.000 claims description 2
- 239000004094 surface-active agent Substances 0.000 claims description 2
- 238000004065 wastewater treatment Methods 0.000 claims description 2
- 239000012736 aqueous medium Substances 0.000 claims 1
- 239000012452 mother liquor Substances 0.000 claims 1
- -1 alkali (Na+/K+) Chemical class 0.000 abstract description 8
- 229910021645 metal ion Inorganic materials 0.000 abstract description 5
- 239000003513 alkali Substances 0.000 abstract description 3
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 17
- 239000000243 solution Substances 0.000 description 13
- 229910052763 palladium Inorganic materials 0.000 description 9
- 229910052709 silver Inorganic materials 0.000 description 9
- 230000015572 biosynthetic process Effects 0.000 description 7
- 230000003993 interaction Effects 0.000 description 7
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 7
- XFXPMWWXUTWYJX-UHFFFAOYSA-N Cyanide Chemical compound N#[C-] XFXPMWWXUTWYJX-UHFFFAOYSA-N 0.000 description 6
- 238000013459 approach Methods 0.000 description 6
- 238000011084 recovery Methods 0.000 description 6
- 239000010944 silver (metal) Substances 0.000 description 6
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 5
- 239000004332 silver Substances 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 229910052697 platinum Inorganic materials 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 229920001864 tannin Polymers 0.000 description 4
- 239000001648 tannin Substances 0.000 description 4
- 235000018553 tannin Nutrition 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 239000007863 gel particle Substances 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 238000003900 soil pollution Methods 0.000 description 3
- 238000003911 water pollution Methods 0.000 description 3
- 238000005033 Fourier transform infrared spectroscopy Methods 0.000 description 2
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- 230000008929 regeneration Effects 0.000 description 2
- 238000011069 regeneration method Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- UMGDCJDMYOKAJW-UHFFFAOYSA-N thiourea Chemical compound NC(N)=S UMGDCJDMYOKAJW-UHFFFAOYSA-N 0.000 description 2
- 230000036962 time dependent Effects 0.000 description 2
- 239000003440 toxic substance Substances 0.000 description 2
- JAJIPIAHCFBEPI-UHFFFAOYSA-N 9,10-dioxoanthracene-1-sulfonic acid Chemical class O=C1C2=CC=CC=C2C(=O)C2=C1C=CC=C2S(=O)(=O)O JAJIPIAHCFBEPI-UHFFFAOYSA-N 0.000 description 1
- 229920000858 Cyclodextrin Polymers 0.000 description 1
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 1
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Natural products NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 1
- NRTCUQNNGVSKSV-UHFFFAOYSA-N [(5-tert-butyl-2-hydroxyphenyl)methylideneamino]thiourea Chemical compound C(C)(C)(C)C=1C=CC(=C(C=NNC(=S)N)C=1)O NRTCUQNNGVSKSV-UHFFFAOYSA-N 0.000 description 1
- HFHDHCJBZVLPGP-RWMJIURBSA-N alpha-cyclodextrin Chemical group OC[C@H]([C@H]([C@@H]([C@H]1O)O)O[C@H]2O[C@@H]([C@@H](O[C@H]3O[C@H](CO)[C@H]([C@@H]([C@H]3O)O)O[C@H]3O[C@H](CO)[C@H]([C@@H]([C@H]3O)O)O[C@H]3O[C@H](CO)[C@H]([C@@H]([C@H]3O)O)O3)[C@H](O)[C@H]2O)CO)O[C@@H]1O[C@H]1[C@H](O)[C@@H](O)[C@@H]3O[C@@H]1CO HFHDHCJBZVLPGP-RWMJIURBSA-N 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 150000001450 anions Chemical class 0.000 description 1
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- 230000033558 biomineral tissue development Effects 0.000 description 1
- 238000006664 bond formation reaction Methods 0.000 description 1
- GQPLZGRPYWLBPW-UHFFFAOYSA-N calix[4]arene Chemical class C1C(C=2)=CC=CC=2CC(C=2)=CC=CC=2CC(C=2)=CC=CC=2CC2=CC=CC1=C2 GQPLZGRPYWLBPW-UHFFFAOYSA-N 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000009388 chemical precipitation Methods 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 150000004696 coordination complex Chemical class 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
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- 239000008103 glucose Substances 0.000 description 1
- 231100001261 hazardous Toxicity 0.000 description 1
- 239000000383 hazardous chemical Substances 0.000 description 1
- 229910001385 heavy metal Inorganic materials 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 238000001727 in vivo Methods 0.000 description 1
- 238000001095 inductively coupled plasma mass spectrometry Methods 0.000 description 1
- 239000002440 industrial waste Substances 0.000 description 1
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- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 239000003446 ligand Substances 0.000 description 1
- 150000002632 lipids Chemical group 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002105 nanoparticle Substances 0.000 description 1
- JMANVNJQNLATNU-UHFFFAOYSA-N oxalonitrile Chemical compound N#CC#N JMANVNJQNLATNU-UHFFFAOYSA-N 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- WXHIJDCHNDBCNY-UHFFFAOYSA-N palladium dihydride Chemical compound [PdH2] WXHIJDCHNDBCNY-UHFFFAOYSA-N 0.000 description 1
- 238000007540 photo-reduction reaction Methods 0.000 description 1
- 239000010970 precious metal Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 108090000623 proteins and genes Chemical group 0.000 description 1
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- 238000007670 refining Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- HRZFUMHJMZEROT-UHFFFAOYSA-L sodium disulfite Chemical compound [Na+].[Na+].[O-]S(=O)S([O-])(=O)=O HRZFUMHJMZEROT-UHFFFAOYSA-L 0.000 description 1
- 229940001584 sodium metabisulfite Drugs 0.000 description 1
- 235000010262 sodium metabisulphite Nutrition 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 230000002269 spontaneous effect Effects 0.000 description 1
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D11/00—Solvent extraction
- B01D11/04—Solvent extraction of solutions which are liquid
- B01D11/0492—Applications, solvents used
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D11/00—Solvent extraction
- B01D11/02—Solvent extraction of solids
- B01D11/0288—Applications, solvents
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D9/00—Crystallisation
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B11/00—Obtaining noble metals
- C22B11/04—Obtaining noble metals by wet processes
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
- C22B3/20—Treatment or purification of solutions, e.g. obtained by leaching
- C22B3/22—Treatment or purification of solutions, e.g. obtained by leaching by physical processes, e.g. by filtration, by magnetic means, or by thermal decomposition
- C22B3/24—Treatment or purification of solutions, e.g. obtained by leaching by physical processes, e.g. by filtration, by magnetic means, or by thermal decomposition by adsorption on solid substances, e.g. by extraction with solid resins
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B61/00—Obtaining metals not elsewhere provided for in this subclass
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Definitions
- the present invention relates to the use of an affordable, selective, and sustainable medium for the industrial extraction of noble metals from a solution containing multiple ions using sustainable composite materials.
- Noble metals are resistant to chemical corrosion. Extraction of noble metals from minerals and their subsequent processing requires highly reactive conditions and toxic chemicals [Environ. Sci. Technol.2005, 39, 4655]. All of the known noble metal extraction processes used in industries are environmentally hazardous due to the use of highly toxic chemicals, which contribute to water and soil pollution. Several methods have been reported earlier for the extraction of different noble metals such as gold (Au), palladium(Pd), silver(Ag), platinum (Pt), etc.[Sci. Rep.2018, 8, 16909; Hydrometallurgy2020, 191, 105241]. It is necessary to have a green and efficient method to extract noble metals. Direct extraction of metal into a solution requires strong interaction of the metal with specific molecules.
- Electrochemical dissolution of noble metals is an important step in extracting, refining, and processing metals [Angew. Chem. Int. Ed. Engl.2011, 50, 6346; ChemCatChem2014, 6, 2219; Nat. Commun.2016, 7, 1]
- the gold extraction is performed by the cyanide method. Typically, this involves chemical and electrochemical methods.
- the extraction process typically followed by the mining industry is cyanidation, which contributes to water and soil pollution [Geotech. Geol. Eng.2006, 24, 1545].
- cyanidation which contributes to water and soil pollution [Geotech. Geol. Eng.2006, 24, 1545].
- a noble metal complex mixture has a large amount of other metals ions.
- electronic waste or industrial waste has other metals in huge concentrations compared to the noble metal.
- it is necessary to develop a green and efficient method to selectively extract different noble metals i.e., Au, Pd, Ag, etc.
- Our methodology and process are very simple, cost-effective, and constitute a green technology for the mining industry.
- the metal extraction process is performed using cyanide, which forms strong complexes with noble metals.
- cyanide forms strong complexes with noble metals.
- the use of cyanide during the extraction process can lead to water and soil pollution.
- the present invention provides a simple and green methodology for extraction of noble metals from ores, using a soft chemistry approach. Selective metal extraction from ores requires strong interaction of the metal with specific molecules, leading to the formation of metal complexes in the solution. These complexes can be further reduced to extract the metal.
- An object of the present invention is to a simple and green methodology for extraction of noble metals from ores, using a soft chemistry approach. Selective metal extraction from ores requires strong interaction of the metal with specific molecules, leading to the formation of metal complexes in the solution. These complexes can be further reduced to extract the metal.
- An object of the present invention is to provide a highly cost-effective and sustainable method of gold extraction in which aqueous Au 3+ is precipitated selectively as it’ s complex with niacin-incorporated polystyrene, with a formula [AuC14]’[2Niacin+H] + -PS.
- the present invention relates to a selective and efficient process for the extraction of noble metal ions from complex mixtures using a sustainable composite materials.
- the present invention relates a simple and green methodology for extraction of noble metals from ores, using a soft chemistry approach. Selective metal extraction from ores requires strong interaction of the metal with specific molecules, leading to the formation of metal complexes in the solution.
- the present invention provide a highly cost-effective and sustainable method of gold extraction in which aqueous Au 3+ is precipitated selectively as it’ s complex with niacin-incorporated polystyrene, with a formula [AuC14]’[2Niacin+H] + -PS abbreviated as complex C, from its mixtures with Be 2+ , Ba 2+ , Sr 2+ ’ Ti 3+ , V 3+ , Cr 3+ , Mn 2+ , Fe 2+ , Co 2+ , Ni 2+ , Cu 2+ ,Cd 2+ , Pb 2+ , AS +3/5 , Sb 3+ , Se 2+ , Sn 2+ , Tl + , Fe 3+ , Pt 2+ , and Zn 2+ , along with common ions such as alkali (Na + /K + ), alkaline earth (Mg 2+ /Ca 2+ ) metal ions and Al 3+ .
- This method such
- the present invention observed that the noble metal ions could be extracted by the PS -niacin composite (composite X).
- the said material is very much effective for harsh industrial conditions such as pH 1 to 3.
- Niacin and styrene being inexpensive, the method may be used for affordable, selective, and sustainable extraction of precious noble metals from diverse raw materials.
- Figure 1 depicts a schematic representation of the synthesis of niacin-incorporated polystyrene (optimized composite X)
- Figure 2 shows FT-IR of PS, niacin, and PS-niacin composite.
- Figure 4 shows pH-dependent study using optimized composite X after 24 h of adsorption with 1 ppm Au 3+ solution.
- Figure 5 Time-dependent adsorption study at pH 1.05 using optimized composite X (100 mg in 100 ml Au solution).
- Figure 6 Regeneration study of Au A) saturated and B) unsaturated adsorbent (composite X) using regenerated solutions.
- Figure 8 shows selective adsorption of different noble metals from a mixture with different input concentrations.
- the present invention relates to a selective and efficient process for the extraction of noble metal ions from complex mixtures using a sustainable composite materials.
- the present invention relates a simple and green methodology for extraction of noble metals from ores, using a soft chemistry approach. Selective metal extraction from ores requires strong interaction of the metal with specific molecules, leading to the formation of metal complexes in the solution.
- the present invention provide a highly cost-effective and sustainable method of gold extraction in which aqueous Au 3+ is precipitated selectively as it’s complex with niacin- incorporated polystyrene, with a formula [AuC14]’[2Niacin+H] + -PS abbreviated as complex C, from its mixtures with Be 2+ , Ba 2+ , Sr 2+ ’ Ti 3+ , V 3+ , Cr 3+ , Mn 2+ , Fe 2+ , Co 2+ , Ni 2+ , Cu 2+ ,Cd 2+ , Pb 2+ , AS +3/5 , Sb 3+ , Se 2+ , Sn 2+ , Tl + , Fe 3+ , Pt 2+ , and Zn 2+ , along with common ions such as alkali (Na + /K + ), alkaline earth (Mg 2+ /Ca 2+ ) metal ions and Al 3+ .
- This method was
- the present invention observed that the noble metal ions could be extracted by the PS-niacin composite (composite X).
- the said material is very much effective for harsh industrial conditions such as pH 1 to 3.
- Niacin and styrene being inexpensive, the method may be used for affordable, selective, and sustainable extraction of precious noble metals from diverse raw materials.
- FIG. 1 depicts the schematic representation of the synthesis of niacin-incorporated polystyrene. Reaction of styrene monomer with niacin at 90 °C with the presence of potassium persulfate (K2S2O8) and surfactant sodium dodecyl sulphate (SDS)in the in situ polymerization process produces niacin-incorporated polystyrene where the active -group of niacin is available for selective Au uptake.
- K2S2O8 potassium persulfate
- SDS sodium dodecyl sulphate
- Figure 2 illustrates FT-IR comparison features of PS, niacin, and PS-niacin composite.
- Characteristic peak -3300-3550 cm’ 1 was observed in Figure 2 (i-iii) due to the O-H frequency of or N-H frequency of the materials.
- Two new peaks at ⁇ 1636 and -1193 cm -1 were observed for the PS-niacin composite, which is due to C-H and N-H bonds, indicating an interaction between PS and niacin. Therefore, bond formation between PS and niacin was proven.
- the presence of both niacin and PS features in the spectra indicates the formation of the niacin-PS composite in Figure 2 iii.
- Figure 3 illustrates an adsorption study using optimized PS-niacin composite X with lower and higher Au 3+ concentrations. In both cases, observed high adsorption capacity - 98.6% and -99.7% for higher and lower concentrations of input Au solution, respectively.
- Figure 4 illustrates a pH-dependent study using the optimized composite X after 24 h of adsorption with 1 ppm Au solution. This study reveals that composite X is very efficient in all the pH (1 to 6.2) shown in the figure.
- Figure 5 illustrates the time-dependent adsorption study at pH 1.05 using optimized composite X. This study has proven that for equilibrium Au adsorption (-99.2 %), time needed is approximately 2-3 h.
- Figure 6 illustrates the regeneration of the adsorbed Au from material X.
- Au recovered from saturated and unsaturated composite X were found to be -93.55% and 51.89%, respectively.
- This invention revealed that the composite X will easily regenerate the surface by a regenerate solution such as sodium metabisulfite (Na2S20s), thiourea (CH4N2S), and different acids. Also, these materials could be used for further adsorption of Au cycles.
- Figure 7 illustrates the effect of adsorption of composite X with various ions, which shows that noble metal ions could be extracted selectively from a complex mixture. There is no effect of other ions on noble metal extraction.
- Figure 8 illustrates selective adsorption of various noble metals from a mixture with different input concentrations, which shows one could tunably extract selective noble metals from its mixture.
- Table 2 revealed that even 10, 100, and 1000 times lesser concentrations of gold could be selectively extracted from its complex mixture with different ions such as Na + , Mg 2+ , Ca 2+ , Al 3+ , SiCh 2 ’, Fe 2+ , Cl’, F’ ions, etc.) at pH 1.05.
- polysulphone PSf
- PVDF polyvinylidene fluoride
- PVA polyvinyl alcohol
- PAN polyacrylonitrile
- PANI polyaniline
- PAA polyacrylic acid
- PAM polyacrylamide
- the composite mixture of the present invention selectively removes the noble metals along with matrices including activated carbon, different graphenic materials, chitosan, cellulose materials and also used in the form of filtration column and filtration vessel.
- the present invention can be used in conjunction with other technology for metal extraction and with a selective electrolyzer electrode system for different noble metals extraction.
- the present invention can be used in various places such as industries relevant to noble metal extraction plants, mining waste, electronic waste, waste water treatment plants.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Chemistry (AREA)
- Metallurgy (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Geochemistry & Mineralogy (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Crystallography & Structural Chemistry (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
The present invention relates to a highly cost-effective and sustainable method of gold extraction in which aqueous Au3+ is precipitated selectively as it's complex with niacin-incorporated polystyrene, with a formula [AuCl4] -[2Niacin+H]+-PS, abbreviated as complex C, from its mixtures with Be2+, Ba2+, Sr2+, Ti 3+, V3+, Cr3+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Cd2+, Pb2+, As+3/5, Sb3+, Se2+, Sn2+, Tl+, Fe3+, Pt2+, and Zn2+, along with common ions such as alkali (Na+/K+), alkaline earth (Mg2+/Ca2+) metal ions and Al3+. The niacin-incorporated polystyrene mixture is very much effective in noble metal extraction from harsh industrial conditions such as pH 1 to 3.
Description
COMPLETESPECIFICATION
TITLE OF THE INVENTION
A SELECTIVE AND EFFICIENT PROCESS FOR THE EXTRACTION OF NOBLE METAL IONS FROM COMPLEX MIXTURES
FIELD OF THE INVENTION
The present invention relates to the use of an affordable, selective, and sustainable medium for the industrial extraction of noble metals from a solution containing multiple ions using sustainable composite materials.
BACKGROUND OF THE INVENTION
Industrial extraction of gold (Au) and other precious noble metals causes a significant environmental impact due to the use of hazardous chemicals such as cyanide, mercury, and acids. Enhancing sustainability by reducing the use of these materials and new process is important in ensuring a safe planet. While there have been many methods introduced in the recent past, extraction with the biomolecule niacin for selective extraction of gold ions gained significant attention [ACS Sustain. Chem. Eng.2021, 9, 2129]. This process has been patented in the recent past [IN202041047984]. However, the use of these technologies industrially would involve the development of appropriate processes so that the chemistry can be utilized economically.
Noble metals are resistant to chemical corrosion. Extraction of noble metals from minerals and their subsequent processing requires highly reactive conditions and toxic chemicals [Environ. Sci. Technol.2005, 39, 4655]. All of the known noble metal extraction processes used in industries are environmentally hazardous due to the use of highly toxic chemicals, which contribute to water and soil pollution. Several methods have been reported earlier for the extraction of different noble metals such as gold (Au), palladium(Pd), silver(Ag), platinum (Pt), etc.[Sci. Rep.2018, 8, 16909; Hydrometallurgy2020, 191, 105241]. It is necessary to have a green and efficient method to extract noble metals. Direct extraction of metal into a solution requires strong interaction of the metal with specific molecules. This is often done with ions such as cyanide, which form strong complexes with noble metals. Different biomolecules such as lipids, carbohydrates, and proteins form weak non-covalent complexes with several metals[Eur.
J. Inorg. Chem.2017, 2017, 3072]. Square -planar tetrahaloaurate anions ([AUX4]-, X = Cl/Br) form inclusion complexes with
and y-CDs [Adv. Funct. Mater.2010, 20, 951], The strong affinity with different functional groups, such as -COOH, -NH2, -SH, -OH, etc., towards metals, including silver and gold, has attracted researchers to create novel nano-biocomposites involving such functionalities [NPG Asia Mater.2013, 5, e39; J. Am. Chem. Soc.2016, 138, 11643]. However, such interactions are weak and, therefore, are rarely used for extraction. Injection of metals into the biological system as ions/complexes has also been reported, where small nanoparticles were synthesized in-vivo, within the bacterial cells, following the biomineralization pathwayfj. Am. Chem. Soc.2016, 138, 11643]. Electrochemical dissolution of noble metals is an important step in extracting, refining, and processing metals [Angew. Chem. Int. Ed. Engl.2011, 50, 6346; ChemCatChem2014, 6, 2219; Nat. Commun.2016, 7, 1]
Typically, extraction of noble metal involves various chemical or electrochemical methods [Environ. Sci. Technol.2005, 39, 4655]. Matthew M. Matlock et al. demonstrated the removal of heavy metals from wastewater derived from the lead battery industry by a chemical precipitation method [Ind. Eng. Chem. Res.2002, 41, 5278]. Because of the slow-leaching rates of silver, G. Deschenes et al. used a high concentration of cyanide to maximize the leaching of silver from high-grade ore samples [Mining, Metall. Explor.2011, 28, 37]. T. Ogata reported a novel recovery system for gold, one of the precious metals in electronic scrap, utilizing tannin gel particles. The adsorption mechanism of gold onto tannin gel particles was also elucidated. The adsorption of gold occurs through the reduction of trivalent gold ions to metallic gold on the surface of tannin gel particles, which is accompanied by simultaneous oxidization of the hydroxyl groups of tannin gel [Water Res.2005, 39, 4281]. Yong Guo et al. demonstrated a photoreduction strategy for selective recovery of gold by carbon nitride[J. Mater. Chem. A2014, 2, 19594]. Z. Liu et al. reported spontaneous assembly of a one-dimensional supramolecular complex with an extended {[K(OH2)e][AuBr4] cz (a-cyclodextrin)2]n chain superstructure, formed during rapid co-precipitation of KAuBr4 and oc -cyclodextrin in water. The phase change is selective for this gold salt, even in presence of other square -planar palladium and platinum complexes[Nat. Commun.2013, 4].
Manabu Yamada et al. reported rapid and selective recovery of palladium (Pd) using a thioamide-modified calix [4] arene adsorbent. Chen Zhou et al. reported palladium recovery in an H2~ based membrane biofilm reactor [Environ. Sci. Technol.2016, 50, 2546]. Damien
bourgeoiset al. reported a process for removal of Pd from printed circuit boards(PCB).Awual et al. reported a ligand-based approach using 5-tert-butyl-2-hydroxybenzaldehyde thiosemicarbazone for efficient palladium(Pd(II)) separation and recovery [Sensors Actuators B Chem.2015, 209, 790]. Baksi et al. reported the selective extraction of silver (Ag) into solution from the bulk metal, by carbohydrates, mainly glucose[Angew. Chemie Int. Ed.2016, 55, 7777]. Youssef Chehade reported recovery of Au, Pd, Ag, etc., from waste PCB.
Globally, the gold extraction is performed by the cyanide method. Typically, this involves chemical and electrochemical methods. The extraction process typically followed by the mining industry is cyanidation, which contributes to water and soil pollution [Geotech. Geol. Eng.2006, 24, 1545]. Generally, a noble metal complex mixture has a large amount of other metals ions. Also, electronic waste or industrial waste has other metals in huge concentrations compared to the noble metal. Thus, it is necessary to develop a green and efficient method to selectively extract different noble metals (i.e., Au, Pd, Ag, etc.). We believe that our recently discovered soft chemistry approach can be efficiently used for different noble metals in industrial conditions. Our methodology and process are very simple, cost-effective, and constitute a green technology for the mining industry.
Globally, the metal extraction process is performed using cyanide, which forms strong complexes with noble metals. However, the use of cyanide during the extraction process can lead to water and soil pollution. Thus the present invention provides a simple and green methodology for extraction of noble metals from ores, using a soft chemistry approach. Selective metal extraction from ores requires strong interaction of the metal with specific molecules, leading to the formation of metal complexes in the solution. These complexes can be further reduced to extract the metal.
OBJECT OF THE INVENTION
An object of the present invention is to a simple and green methodology for extraction of noble metals from ores, using a soft chemistry approach. Selective metal extraction from ores requires strong interaction of the metal with specific molecules, leading to the formation of metal complexes in the solution. These complexes can be further reduced to extract the metal.
An object of the present invention is to provide a highly cost-effective and sustainable method of gold extraction in which aqueous Au3+ is precipitated selectively as it’ s complex with niacin-incorporated polystyrene, with a formula [AuC14]’[2Niacin+H]+-PS.
SUMMARY OF THE INVENTION
The present invention relates to a selective and efficient process for the extraction of noble metal ions from complex mixtures using a sustainable composite materials.
In one embodiment, the present invention relates a simple and green methodology for extraction of noble metals from ores, using a soft chemistry approach. Selective metal extraction from ores requires strong interaction of the metal with specific molecules, leading to the formation of metal complexes in the solution.
In one embodiment, the present invention provide a highly cost-effective and sustainable method of gold extraction in which aqueous Au3+ is precipitated selectively as it’ s complex with niacin-incorporated polystyrene, with a formula [AuC14]’[2Niacin+H]+-PS abbreviated as complex C, from its mixtures with Be2+, Ba2+, Sr2+’ Ti3+, V3+, Cr3+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+,Cd2+, Pb2+, AS+3/5, Sb3+, Se2+, Sn2+, Tl+, Fe3+, Pt2+, and Zn2+, along with common ions such as alkali (Na+/K+), alkaline earth (Mg2+/Ca2+) metal ions and Al3+.This method was also employed to extract other noble metals such as Pd, Ag, and Pt from the mixture of other reactive metal ions mixture (such as Au3+, Pd2+, Rh3+, Ru3+, Ag+, Hf4+, Ir4+, Te2+, Pt2+, etc.). The present invention observed that the noble metal ions could be extracted by the PS -niacin composite (composite X). The said material is very much effective for harsh industrial conditions such as pH 1 to 3. Niacin and styrene, being inexpensive, the method may be used for affordable, selective, and sustainable extraction of precious noble metals from diverse raw materials.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 depicts a schematic representation of the synthesis of niacin-incorporated polystyrene (optimized composite X)
Figure 2 shows FT-IR of PS, niacin, and PS-niacin composite.
Figure 3 A) Au3+ adsorption study using optimized PS-niacin composite X; B) is the expanded view of A.
Figure 4 shows pH-dependent study using optimized composite X after 24 h of adsorption with 1 ppm Au3+solution.
Figure 5 Time-dependent adsorption study at pH 1.05 using optimized composite X (100 mg in 100 ml Au solution).
Figure 6 Regeneration study of Au A) saturated and B) unsaturated adsorbent (composite X) using regenerated solutions.
Figure 7 Effect of adsorption of composite X with various ions.
Figure 8 shows selective adsorption of different noble metals from a mixture with different input concentrations.
Referring to the drawings, the embodiments of the present invention are further described. The figures are not necessarily drawn to scale, and in some instances, the drawings have been exaggerated or simplified for illustrative purposes only. One of the ordinary skills in the art may appreciate the many possible applications and variations of the present invention based on the following examples of possible embodiments of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The following description is presented to enable any person skilled in the art to make and use the embodiments, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the scope of the present disclosure. Thus, the present invention is not limited to the embodiments shown but is to be accorded the widest scope consistent with the principles and features disclosed herein.
The present invention relates to a selective and efficient process for the extraction of noble metal ions from complex mixtures using a sustainable composite materials.
The present invention relates a simple and green methodology for extraction of noble metals from ores, using a soft chemistry approach. Selective metal extraction from ores requires strong interaction of the metal with specific molecules, leading to the formation of metal complexes in the solution.
The present invention provide a highly cost-effective and sustainable method of gold extraction in which aqueous Au3+ is precipitated selectively as it’s complex with niacin- incorporated polystyrene, with a formula [AuC14]’[2Niacin+H]+-PS abbreviated as complex C, from its mixtures with Be2+, Ba2+, Sr2+’ Ti3+, V3+, Cr3+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+,Cd2+, Pb2+, AS+3/5, Sb3+, Se2+, Sn2+, Tl+, Fe3+, Pt2+, and Zn2+, along with common ions such as alkali (Na+/K+), alkaline earth (Mg2+/Ca2+) metal ions and Al3+.This method was also employed to
extract other noble metals such as Pd, Ag, and Pt from the mixture of other reactive metal ions mixture (such as Au3+, Pd2+, Rh3+, Ru3+, Ag+, Hf +, Ir4+, Te2+, Pt2+, etc.). The present invention observed that the noble metal ions could be extracted by the PS-niacin composite (composite X). The said material is very much effective for harsh industrial conditions such as pH 1 to 3. Niacin and styrene, being inexpensive, the method may be used for affordable, selective, and sustainable extraction of precious noble metals from diverse raw materials.
The present invention relates to the development of a selective, affordable and sustainable media for industrial Au extraction. Figure 1 depicts the schematic representation of the synthesis of niacin-incorporated polystyrene. Reaction of styrene monomer with niacin at 90 °C with the presence of potassium persulfate (K2S2O8) and surfactant sodium dodecyl sulphate (SDS)in the in situ polymerization process produces niacin-incorporated polystyrene where the active -group of niacin is available for selective Au uptake.
Figure 2 (Ai-Aiii) illustrates FT-IR comparison features of PS, niacin, and PS-niacin composite. Characteristic peak -3300-3550 cm’1 was observed in Figure 2 (i-iii) due to the O-H frequency of or N-H frequency of the materials. The characteristic peak around 3025 cm’1 for the C-H aromatic bond, peaks at 2920 and 2849 cm’1 due to aliphatic C-H are observable. Two new peaks at~1636 and -1193 cm-1were observed for the PS-niacin composite, which is due to C-H and N-H bonds, indicating an interaction between PS and niacin. Therefore, bond formation between PS and niacin was proven. The presence of both niacin and PS features in the spectra indicates the formation of the niacin-PS composite in Figure 2 iii.
Figure 3 (A and B) illustrates an adsorption study using optimized PS-niacin composite X with lower and higher Au3+ concentrations. In both cases, observed high adsorption capacity - 98.6% and -99.7% for higher and lower concentrations of input Au solution, respectively.
Figure 4 illustrates a pH-dependent study using the optimized composite X after 24 h of adsorption with 1 ppm Au solution. This study reveals that composite X is very efficient in all the pH (1 to 6.2) shown in the figure.
Figure 5 illustrates the time-dependent adsorption study at pH 1.05 using optimized composite X. This study has proven that for equilibrium Au adsorption (-99.2 %), time needed is approximately 2-3 h.
Figure 6 illustrates the regeneration of the adsorbed Au from material X. Au recovered from saturated and unsaturated composite X were found to be -93.55% and 51.89%,
respectively. This invention revealed that the composite X will easily regenerate the surface by a regenerate solution such as sodium metabisulfite (Na2S20s), thiourea (CH4N2S), and different acids. Also, these materials could be used for further adsorption of Au cycles.
Figure 7 illustrates the effect of adsorption of composite X with various ions, which shows that noble metal ions could be extracted selectively from a complex mixture. There is no effect of other ions on noble metal extraction.
Figure 8 illustrates selective adsorption of various noble metals from a mixture with different input concentrations, which shows one could tunably extract selective noble metals from its mixture.
The results presented above demonstrate the preparation and utilization of niacin- incorporated polystyrene for industrial applications. Chemical analysis of the mining sample before and after niacin-incorporated PS (composite X) treatment is presented in Table 1. This shows 99.5 % of Au3+removal, and the concentration of other elements is unaffected. This happened at industrial relevance pH conditions such as pH 1 to 3. This selectivity adds another advantage to the process wherein precious noble metals recovered from diverse raw materials, could be left undisturbed for subsequent processes. Also, Table 2 revealed that even 10, 100, and 1000 times lesser concentrations of gold could be selectively extracted from its complex mixture with different ions such as Na+, Mg2+, Ca2+, Al3+, SiCh2’, Fe2+, Cl’, F’ ions, etc.) at pH 1.05. Tablel Au3+ adsorption data before and after reaction with niacin-incorporated PS materials and ICP-MS data.
Table 2 Adsorption study of composite X in a 5 mL mixture (where Au=gold and M= mixture of multi-ions used such as Na+, Mg2+, Ca2+, Al3+, SiC>32’, Fe2+, Cl’, F", etc.) at pH 1.05.
The stability of the polymeric system under such harsh conditions is important for industrial applications. The present invention used polystyrene in this process to make it economical. Other polymers such as polysulphone (PSf), polyvinylidene fluoride (PVDF), polyvinyl alcohol (PVA), polyacrylonitrile (PAN), polyaniline (PANI), polyacrylic acid (PAA)and polyacrylamide (PAM)can also be used as matrices for this process. However, the environmental sustainability of the materials has to be accessed suitably. The composite mixture of the present invention selectively removes the noble metals along with matrices including activated carbon, different graphenic materials, chitosan, cellulose materials and also used in the form of filtration column and filtration vessel. The present invention can be used in conjunction with other technology for metal extraction and with a selective electrolyzer electrode system for different noble metals extraction. The present invention can be used in various places such as industries relevant to noble metal extraction plants, mining waste, electronic waste, waste water treatment plants.
It may be appreciated by those skilled in the art that the drawings, examples and detailed description herein are to be regarded in an illustrative rather than a restrictive manner.
Claims
1. A process for the selective extraction of noble metal ions, comprising a. reacting styrene monomer with niacin at 90°Cwith the presence of potassium persulfate (K2S2O8) and surfactant sodium dodecyl sulphate (SDS); b. obtaining a niacin-incorporated polystyrene composite from step (a) via in situ polymerization which act as polymeric adsorbent; c. exposing the noble metal containing ionic mixture to the niacin-incorporated polystyrene to form a complex; d. separating the noble metal adsorbed polystyrene-niacin complex characterized in that, a polystyrene-niacin composite selectively adsorb noble metal ions from a solution containing multiple ions from harsh industrial conditions with pH 1 to 3.
2. The process as claimed in claim 1, wherein the noble metal extraction includes Au3+,Pd2+, Rh3+, RU3+, Ag+, Hf4+, Ir4+, Te2+,Pt2+.
3. The process as claimed in claim 1, wherein the niacin-incorporated polystyrene form a complex with gold with a formula [AuC14]’[2Niacin+H]+-PS with -99.2 % adsorption capacity in 2-3 h at pH 1.05.
4. The process as claimed in claim 1, wherein the noble metal containing ionic mixture composed of different ions includes Li+, Be2+, Na+, Mg2+, Al3+, K+, Ca2+, Sr2+,Ba2+, Ti3+,
5. The process as claimed in claim 1, wherein the Au recovered from saturated and unsaturated composite are -93.55% and 51.89%, respectively.
6. The process as claimed in claim 2, wherein the aqueous medium contains various metals in ionic form with concentrations of 10, 100, and 1000 times than noble metals ions present in the mixture.
7. The process as claimed in claim 2, wherein the concentration of Au3+ in the final mother liquor after extraction is below -2 ppb.
8. The process as claimed in claim 1, wherein the polymer is selected from polysulfone (PSf), polyvinylidene fluoride (PVDF), polyvinyl alcohol (PVA), polyacrylonitrile (PAN), polyaniline (PANI), polyacrylic acid (PAA), polyacrylamide (PAM).
The process as claimed in claim 1, wherein the polymer adsorbent selectively removes the noble metals along with matrices including activated carbon, different graphenic materials, chitosan, cellulose materials. The process as claimed in claim 1, wherein the polymeric adsorbent is used in the form of filtration column and filtration vessel. The process as claimed in claim 1, wherein the polymeric adsorbent is used in conjunction with other technology for metal extraction. The process as claimed in claim 1, wherein the polymeric adsorbent is used with a selective electrolyzer electrode system for different noble metals extraction. The process as claimed in claim 1, wherein the polymeric adsorbent is used in various places such as industry relevant to noble metal extraction plants, mining waste, electronic waste, waste water treatment plants. The process as claimed in claim 1, wherein the polymeric adsorbent is used with a selective electrolyzer electrode system for different noble metals extraction.
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