EP3256248A1 - Catalyst for direct synthesis of hydrogen peroxide - Google Patents
Catalyst for direct synthesis of hydrogen peroxideInfo
- Publication number
- EP3256248A1 EP3256248A1 EP16704892.5A EP16704892A EP3256248A1 EP 3256248 A1 EP3256248 A1 EP 3256248A1 EP 16704892 A EP16704892 A EP 16704892A EP 3256248 A1 EP3256248 A1 EP 3256248A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- catalyst
- metal species
- metal
- hydrogen peroxide
- species
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 239000003054 catalyst Substances 0.000 title claims abstract description 448
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 title claims abstract description 196
- 238000003786 synthesis reaction Methods 0.000 title claims abstract description 60
- 230000015572 biosynthetic process Effects 0.000 title claims abstract description 58
- 239000002105 nanoparticle Substances 0.000 claims abstract description 63
- 238000000034 method Methods 0.000 claims abstract description 61
- 230000003197 catalytic effect Effects 0.000 claims abstract description 50
- 238000004519 manufacturing process Methods 0.000 claims abstract description 38
- 229910052751 metal Inorganic materials 0.000 claims description 207
- 239000002184 metal Substances 0.000 claims description 207
- KDLHZDBZIXYQEI-UHFFFAOYSA-N palladium Substances [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims description 176
- 229910052763 palladium Inorganic materials 0.000 claims description 104
- 239000011135 tin Substances 0.000 claims description 98
- 229910052718 tin Inorganic materials 0.000 claims description 70
- 238000007254 oxidation reaction Methods 0.000 claims description 47
- 238000005984 hydrogenation reaction Methods 0.000 claims description 44
- 229910052759 nickel Inorganic materials 0.000 claims description 40
- 230000003647 oxidation Effects 0.000 claims description 40
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 39
- 239000001257 hydrogen Substances 0.000 claims description 38
- 229910052739 hydrogen Inorganic materials 0.000 claims description 38
- 230000000694 effects Effects 0.000 claims description 34
- 229910001868 water Inorganic materials 0.000 claims description 33
- 230000002829 reductive effect Effects 0.000 claims description 31
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 30
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 30
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 24
- 239000012018 catalyst precursor Substances 0.000 claims description 24
- 239000001301 oxygen Substances 0.000 claims description 24
- 229910052760 oxygen Inorganic materials 0.000 claims description 24
- 239000002904 solvent Substances 0.000 claims description 18
- -1 for example Substances 0.000 claims description 14
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims description 13
- 230000001590 oxidative effect Effects 0.000 claims description 12
- 229910052725 zinc Inorganic materials 0.000 claims description 12
- 239000012298 atmosphere Substances 0.000 claims description 10
- 239000000956 alloy Substances 0.000 claims description 9
- 239000006227 byproduct Substances 0.000 claims description 7
- 229910003455 mixed metal oxide Inorganic materials 0.000 claims description 6
- 239000002699 waste material Substances 0.000 claims description 6
- 229910052802 copper Inorganic materials 0.000 claims description 5
- 229910001092 metal group alloy Inorganic materials 0.000 claims description 5
- 239000007844 bleaching agent Substances 0.000 claims description 4
- 229910052804 chromium Inorganic materials 0.000 claims description 4
- 238000005868 electrolysis reaction Methods 0.000 claims description 4
- 229910052733 gallium Inorganic materials 0.000 claims description 4
- 229910052732 germanium Inorganic materials 0.000 claims description 4
- 229910052738 indium Inorganic materials 0.000 claims description 4
- 229910052742 iron Inorganic materials 0.000 claims description 4
- 229910052697 platinum Inorganic materials 0.000 claims description 4
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Substances [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 4
- 229910052741 iridium Inorganic materials 0.000 claims description 2
- 229910052750 molybdenum Inorganic materials 0.000 claims description 2
- 229910052762 osmium Inorganic materials 0.000 claims description 2
- 229910052703 rhodium Inorganic materials 0.000 claims description 2
- 229910052707 ruthenium Inorganic materials 0.000 claims description 2
- 229910052721 tungsten Inorganic materials 0.000 claims description 2
- 230000008569 process Effects 0.000 abstract description 26
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 47
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 36
- 238000011282 treatment Methods 0.000 description 33
- 238000006243 chemical reaction Methods 0.000 description 29
- 238000006722 reduction reaction Methods 0.000 description 27
- 238000010438 heat treatment Methods 0.000 description 26
- 230000009467 reduction Effects 0.000 description 26
- 229910052681 coesite Inorganic materials 0.000 description 25
- 229910052906 cristobalite Inorganic materials 0.000 description 25
- 229910052682 stishovite Inorganic materials 0.000 description 25
- 229910052905 tridymite Inorganic materials 0.000 description 25
- 239000000523 sample Substances 0.000 description 21
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 20
- 239000000203 mixture Substances 0.000 description 20
- 239000000243 solution Substances 0.000 description 20
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N titanium dioxide Inorganic materials O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 20
- 238000001354 calcination Methods 0.000 description 19
- XOLBLPGZBRYERU-UHFFFAOYSA-N SnO2 Inorganic materials O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 description 16
- 241000894007 species Species 0.000 description 15
- 239000011701 zinc Substances 0.000 description 15
- 238000001350 scanning transmission electron microscopy Methods 0.000 description 14
- 238000004833 X-ray photoelectron spectroscopy Methods 0.000 description 13
- 238000004458 analytical method Methods 0.000 description 13
- 150000003839 salts Chemical class 0.000 description 11
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 10
- 238000002441 X-ray diffraction Methods 0.000 description 10
- PYKYMHQGRFAEBM-UHFFFAOYSA-N anthraquinone Natural products CCC(=O)c1c(O)c2C(=O)C3C(C=CC=C3O)C(=O)c2cc1CC(=O)OC PYKYMHQGRFAEBM-UHFFFAOYSA-N 0.000 description 10
- 150000004056 anthraquinones Chemical class 0.000 description 10
- 229910052786 argon Inorganic materials 0.000 description 10
- 238000000354 decomposition reaction Methods 0.000 description 10
- 238000002360 preparation method Methods 0.000 description 10
- 238000000026 X-ray photoelectron spectrum Methods 0.000 description 8
- 229910052799 carbon Inorganic materials 0.000 description 8
- 150000002431 hydrogen Chemical class 0.000 description 8
- 239000000463 material Substances 0.000 description 8
- 239000002245 particle Substances 0.000 description 8
- 239000002253 acid Substances 0.000 description 7
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 6
- 239000002243 precursor Substances 0.000 description 6
- 238000003756 stirring Methods 0.000 description 6
- 238000012360 testing method Methods 0.000 description 6
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 5
- 229910000355 cerium(IV) sulfate Inorganic materials 0.000 description 5
- 238000002149 energy-dispersive X-ray emission spectroscopy Methods 0.000 description 5
- 239000007789 gas Substances 0.000 description 5
- 239000010931 gold Substances 0.000 description 5
- 238000005470 impregnation Methods 0.000 description 5
- 238000000634 powder X-ray diffraction Methods 0.000 description 5
- 239000000377 silicon dioxide Substances 0.000 description 5
- 239000000126 substance Substances 0.000 description 5
- 229910002651 NO3 Inorganic materials 0.000 description 4
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 4
- 229910002677 Pd–Sn Inorganic materials 0.000 description 4
- 229910045601 alloy Inorganic materials 0.000 description 4
- 238000000151 deposition Methods 0.000 description 4
- CIWXFRVOSDNDJZ-UHFFFAOYSA-L ferroin Chemical compound [Fe+2].[O-]S([O-])(=O)=O.C1=CN=C2C3=NC=CC=C3C=CC2=C1.C1=CN=C2C3=NC=CC=C3C=CC2=C1.C1=CN=C2C3=NC=CC=C3C=CC2=C1 CIWXFRVOSDNDJZ-UHFFFAOYSA-L 0.000 description 4
- 150000004820 halides Chemical class 0.000 description 4
- 230000003993 interaction Effects 0.000 description 4
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 3
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 3
- 229910002666 PdCl2 Inorganic materials 0.000 description 3
- DNIAPMSPPWPWGF-UHFFFAOYSA-N Propylene glycol Chemical compound CC(O)CO DNIAPMSPPWPWGF-UHFFFAOYSA-N 0.000 description 3
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- 230000003247 decreasing effect Effects 0.000 description 3
- MTHSVFCYNBDYFN-UHFFFAOYSA-N diethylene glycol Chemical compound OCCOCCO MTHSVFCYNBDYFN-UHFFFAOYSA-N 0.000 description 3
- 229910052737 gold Inorganic materials 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 238000011068 loading method Methods 0.000 description 3
- 239000002609 medium Substances 0.000 description 3
- 229910044991 metal oxide Inorganic materials 0.000 description 3
- 150000004706 metal oxides Chemical class 0.000 description 3
- 238000000386 microscopy Methods 0.000 description 3
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- PIBWKRNGBLPSSY-UHFFFAOYSA-L palladium(II) chloride Chemical compound Cl[Pd]Cl PIBWKRNGBLPSSY-UHFFFAOYSA-L 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 238000000851 scanning transmission electron micrograph Methods 0.000 description 3
- 238000001228 spectrum Methods 0.000 description 3
- 239000003381 stabilizer Substances 0.000 description 3
- 229910002710 Au-Pd Inorganic materials 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 2
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 2
- 229910017356 Fe2C Inorganic materials 0.000 description 2
- OAKJQQAXSVQMHS-UHFFFAOYSA-N Hydrazine Chemical compound NN OAKJQQAXSVQMHS-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- CPELXLSAUQHCOX-UHFFFAOYSA-N Hydrogen bromide Chemical compound Br CPELXLSAUQHCOX-UHFFFAOYSA-N 0.000 description 2
- 108010018961 N(5)-(carboxyethyl)ornithine synthase Proteins 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 229910002855 Sn-Pd Inorganic materials 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 230000002378 acidificating effect Effects 0.000 description 2
- 150000007513 acids Chemical class 0.000 description 2
- 239000003570 air Substances 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 230000015556 catabolic process Effects 0.000 description 2
- 238000005119 centrifugation Methods 0.000 description 2
- 238000012512 characterization method Methods 0.000 description 2
- 239000003153 chemical reaction reagent Substances 0.000 description 2
- 239000003638 chemical reducing agent Substances 0.000 description 2
- 239000000460 chlorine Substances 0.000 description 2
- 229910052801 chlorine Inorganic materials 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000002447 crystallographic data Methods 0.000 description 2
- 238000010908 decantation Methods 0.000 description 2
- 230000008021 deposition Effects 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 150000002009 diols Chemical class 0.000 description 2
- OSVXSBDYLRYLIG-UHFFFAOYSA-N dioxidochlorine(.) Chemical compound O=Cl=O OSVXSBDYLRYLIG-UHFFFAOYSA-N 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 229910002804 graphite Inorganic materials 0.000 description 2
- 239000010439 graphite Substances 0.000 description 2
- 239000011964 heteropoly acid Substances 0.000 description 2
- 238000004128 high performance liquid chromatography Methods 0.000 description 2
- WQYVRQLZKVEZGA-UHFFFAOYSA-N hypochlorite Chemical compound Cl[O-] WQYVRQLZKVEZGA-UHFFFAOYSA-N 0.000 description 2
- 238000011065 in-situ storage Methods 0.000 description 2
- 238000011835 investigation Methods 0.000 description 2
- 229910021645 metal ion Chemical class 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 description 2
- 150000007522 mineralic acids Chemical class 0.000 description 2
- 239000007800 oxidant agent Substances 0.000 description 2
- RVTZCBVAJQQJTK-UHFFFAOYSA-N oxygen(2-);zirconium(4+) Chemical compound [O-2].[O-2].[Zr+4] RVTZCBVAJQQJTK-UHFFFAOYSA-N 0.000 description 2
- GPNDARIEYHPYAY-UHFFFAOYSA-N palladium(ii) nitrate Chemical compound [Pd+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O GPNDARIEYHPYAY-UHFFFAOYSA-N 0.000 description 2
- VLTRZXGMWDSKGL-UHFFFAOYSA-N perchloric acid Chemical compound OCl(=O)(=O)=O VLTRZXGMWDSKGL-UHFFFAOYSA-N 0.000 description 2
- 230000001737 promoting effect Effects 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 239000001509 sodium citrate Substances 0.000 description 2
- 125000006850 spacer group Chemical group 0.000 description 2
- 239000007858 starting material Substances 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- 239000001117 sulphuric acid Substances 0.000 description 2
- 235000011149 sulphuric acid Nutrition 0.000 description 2
- 238000001308 synthesis method Methods 0.000 description 2
- JIAARYAFYJHUJI-UHFFFAOYSA-L zinc dichloride Chemical compound [Cl-].[Cl-].[Zn+2] JIAARYAFYJHUJI-UHFFFAOYSA-L 0.000 description 2
- 229910001928 zirconium oxide Inorganic materials 0.000 description 2
- BZSXEZOLBIJVQK-UHFFFAOYSA-N 2-methylsulfonylbenzoic acid Chemical compound CS(=O)(=O)C1=CC=CC=C1C(O)=O BZSXEZOLBIJVQK-UHFFFAOYSA-N 0.000 description 1
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 description 1
- 241000894006 Bacteria Species 0.000 description 1
- CPELXLSAUQHCOX-UHFFFAOYSA-M Bromide Chemical compound [Br-] CPELXLSAUQHCOX-UHFFFAOYSA-M 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- 239000004155 Chlorine dioxide Substances 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910002483 Cu Ka Inorganic materials 0.000 description 1
- 101000694017 Homo sapiens Sodium channel protein type 5 subunit alpha Proteins 0.000 description 1
- 229910021586 Nickel(II) chloride Inorganic materials 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 1
- 239000012494 Quartz wool Substances 0.000 description 1
- 229910008433 SnCU Inorganic materials 0.000 description 1
- 239000004280 Sodium formate Substances 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- ZMZDMBWJUHKJPS-UHFFFAOYSA-M Thiocyanate anion Chemical compound [S-]C#N ZMZDMBWJUHKJPS-UHFFFAOYSA-M 0.000 description 1
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical class O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 1
- 239000002390 adhesive tape Substances 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 229910000905 alloy phase Inorganic materials 0.000 description 1
- 229910021417 amorphous silicon Inorganic materials 0.000 description 1
- 239000012736 aqueous medium Substances 0.000 description 1
- 125000004429 atom Chemical group 0.000 description 1
- AZWXAPCAJCYGIA-UHFFFAOYSA-N bis(2-methylpropyl)alumane Chemical compound CC(C)C[AlH]CC(C)C AZWXAPCAJCYGIA-UHFFFAOYSA-N 0.000 description 1
- 239000006229 carbon black Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000001311 chemical methods and process Methods 0.000 description 1
- 231100000481 chemical toxicant Toxicity 0.000 description 1
- 150000001805 chlorine compounds Chemical group 0.000 description 1
- 235000019398 chlorine dioxide Nutrition 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 229910002026 crystalline silica Inorganic materials 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 239000000645 desinfectant Substances 0.000 description 1
- SIPUZPBQZHNSDW-UHFFFAOYSA-N diisobutylaluminium hydride Substances CC(C)C[Al]CC(C)C SIPUZPBQZHNSDW-UHFFFAOYSA-N 0.000 description 1
- SZXQTJUDPRGNJN-UHFFFAOYSA-N dipropylene glycol Chemical compound OCCCOCCCO SZXQTJUDPRGNJN-UHFFFAOYSA-N 0.000 description 1
- 239000002526 disodium citrate Substances 0.000 description 1
- 235000019262 disodium citrate Nutrition 0.000 description 1
- CEYULKASIQJZGP-UHFFFAOYSA-L disodium;2-(carboxymethyl)-2-hydroxybutanedioate Chemical compound [Na+].[Na+].[O-]C(=O)CC(O)(C(=O)O)CC([O-])=O CEYULKASIQJZGP-UHFFFAOYSA-L 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000004070 electrodeposition Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 235000019253 formic acid Nutrition 0.000 description 1
- 229910021397 glassy carbon Inorganic materials 0.000 description 1
- 150000002334 glycols Chemical class 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 231100001261 hazardous Toxicity 0.000 description 1
- 229910000042 hydrogen bromide Inorganic materials 0.000 description 1
- ZMZDMBWJUHKJPS-UHFFFAOYSA-N hydrogen thiocyanate Natural products SC#N ZMZDMBWJUHKJPS-UHFFFAOYSA-N 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 230000003278 mimic effect Effects 0.000 description 1
- 239000002808 molecular sieve Substances 0.000 description 1
- 239000002048 multi walled nanotube Substances 0.000 description 1
- QMMRZOWCJAIUJA-UHFFFAOYSA-L nickel dichloride Chemical compound Cl[Ni]Cl QMMRZOWCJAIUJA-UHFFFAOYSA-L 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 230000033116 oxidation-reduction process Effects 0.000 description 1
- 235000011007 phosphoric acid Nutrition 0.000 description 1
- 239000010970 precious metal Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 238000003608 radiolysis reaction Methods 0.000 description 1
- 239000012429 reaction media Substances 0.000 description 1
- 230000027756 respiratory electron transport chain Effects 0.000 description 1
- 238000013341 scale-up Methods 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 239000002109 single walled nanotube Substances 0.000 description 1
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 description 1
- NLJMYIDDQXHKNR-UHFFFAOYSA-K sodium citrate Chemical compound O.O.[Na+].[Na+].[Na+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O NLJMYIDDQXHKNR-UHFFFAOYSA-K 0.000 description 1
- 235000011083 sodium citrates Nutrition 0.000 description 1
- HLBBKKJFGFRGMU-UHFFFAOYSA-M sodium formate Chemical compound [Na+].[O-]C=O HLBBKKJFGFRGMU-UHFFFAOYSA-M 0.000 description 1
- 235000019254 sodium formate Nutrition 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 229910021653 sulphate ion Inorganic materials 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 238000002076 thermal analysis method Methods 0.000 description 1
- 238000004448 titration Methods 0.000 description 1
- 239000003440 toxic substance Substances 0.000 description 1
- HRXKRNGNAMMEHJ-UHFFFAOYSA-K trisodium citrate Chemical compound [Na+].[Na+].[Na+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O HRXKRNGNAMMEHJ-UHFFFAOYSA-K 0.000 description 1
- 229940038773 trisodium citrate Drugs 0.000 description 1
- 235000019263 trisodium citrate Nutrition 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
- 239000010457 zeolite Substances 0.000 description 1
- 239000011592 zinc chloride Substances 0.000 description 1
- 235000005074 zinc chloride Nutrition 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
- B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
- B01J23/56—Platinum group metals
- B01J23/62—Platinum group metals with gallium, indium, thallium, germanium, tin or lead
- B01J23/622—Platinum group metals with gallium, indium, thallium, germanium, tin or lead with germanium, tin or lead
- B01J23/626—Platinum group metals with gallium, indium, thallium, germanium, tin or lead with germanium, tin or lead with tin
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
- B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
- B01J23/56—Platinum group metals
- B01J23/60—Platinum group metals with zinc, cadmium or mercury
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
- B01J23/89—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals
- B01J23/892—Nickel and noble metals
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/12—Oxidising
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/16—Reducing
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B15/00—Peroxides; Peroxyhydrates; Peroxyacids or salts thereof; Superoxides; Ozonides
- C01B15/01—Hydrogen peroxide
- C01B15/029—Preparation from hydrogen and oxygen
Definitions
- the present invention is directed to catalytic nanoparticles and catalysts comprising same which are suitable for direct synthesis of hydrogen peroxide, to a process for manufacturing catalysts comprising said catalytic nanoparticles, to the use of said catalysts for direct synthesis of hydrogen peroxide, and to a method of manufacturing hydrogen peroxide by direct synthesis using said catalysts.
- Hydrogen peroxide is a simple inorganic molecule and since its discovery has been an important commodity chemical with both industrial and domestic uses.
- the annual production of H2O2 stood at around 4 million metric tonnes increasing by 4 % annually.
- Around 40 % of H2O2 is used in the pulp and paper industry as an alternative to chlorine-containing oxidants such as chlorine dioxide and sodium chlorate.
- Another major use is in water purification where H2O2 has been shown to destroy thiocyanate, nitrate, chlorine, hypochlorite and other potentially toxic chemicals which may be present in waste water.
- H2O2 Over 90 % of the world's H2O2 is manufactured by the indirect anthraquinone process, otherwise known as the auto-oxidation process.
- This process involves the hydrogenation of a substituted anthraquinone using a nickel or palladium catalyst to form a diol.
- the diol is then oxidised by an O2 rich aid feed to form the original anthraquinone and give H2O2 as a by-product. While this process is now large scale and energy efficient, there remain a number of problems associated with the anthraquinone process.
- the anthraquinone process is only viable on a large scale which means that concentrated H2O2 (70 wt%) solutions need to be stored and transported which can be hazardous, and the solutions may require the addition of acid or halide as stabilisers. While the process is operated at mild temperature and pressure, anthraquinone derivatives can be formed irreversibly which do not participate in the formation of H2O2. This means that the original anthraquinone molecule needs to be continually added to maintain the efficiency of the system. The use of a highly active hydrogenation catalyst can also result in the decomposition of the anthraquinone again reducing the efficiency of the system.
- Pd catalysts which are active for H2O2 synthesis also tend to be active for the subsequent hydrogenation and decomposition of H2O2 resulting in lower overall yield and reduced H2O2 selectivity.
- the addition of halides and acids, either added to the reaction solution or incorporated into the catalyst, have been used to suppress the competing hydrogenation and decomposition reactions leading to improved yields of H2O2.
- Au-Pd bimetallic catalysts are more active and selective for the direct synthesis of H2O2 than monometallic palladium catalysts (see, for example, WO-A-2007007075 and WO-A-2012171892).
- a catalytic nanoparticle formed during manufacture of a catalyst for direct synthesis of hydrogen peroxide, said catalytic nanoparticle comprising a first metal species and at least one second metal species, wherein the first metal species in monometallic form has an activity for hydrogenation, and the at least one second metal species in monometallic form does not decompose hydrogen peroxide, and wherein the first metal species and the second metal species are different, and if the catalytic nanoparticle comprises only one second metal species, the second metal species is other than tin.
- a catalyst for direct synthesis of hydrogen peroxide comprising catalytic nanoparticles according to the first aspect.
- a catalyst for direct synthesis of hydrogen peroxide comprising a first metal species and at least one second metal species, wherein the first metal species in monometallic form has an activity for hydrogenation, and the at least one second metal species in monometallic form does not decompose hydrogen peroxide, wherein if the catalyst comprises only one second metal species it is other than tin, wherein the combined amount of the first and second metal species is less than 15 wt. % of the catalyst, and wherein the catalyst comprises at least about 0.25 wt. % of the first metal species, based on the total weight of the catalyst.
- a method for making a catalyst comprising catalytic nanoparticles comprising (i) preparing, providing or obtaining a catalyst precursor comprising catalyst support, a first metal species and at least one second metal species, wherein the first metal species in monometallic form has an activity for hydrogenation, and the at least one second metal species in monometallic form does not decompose hydrogen peroxide, (ii) treating the catalyst precursor under oxidizing conditions in a first step, (iii) treating the oxidised catalyst under reducing conditions in a second step, and (iv) treating the reduced catalyst under oxidising conditions at an elevated temperature in a third step (i.e., prior to use of the catalyst in the direct synthesis of hydrogen peroxide), wherein if the catalyst precursor comprises only one second metal species, the second metal species is other than tin.
- a method of making hydrogen peroxide by direct synthesis comprising converting hydrogen and oxygen to hydrogen peroxide in the presence of:
- catalytic nanoparticles comprising a mixed metal oxide and/or alloy of a first metal and at least one second metal, wherein the first metal in monometallic form has an activity for hydrogenation, and the at least one second metal in monometallic form does not decompose hydrogen peroxide; or
- a catalyst comprising a first metal species and at least one second metal species, wherein the first metal species in monometallic form has an activity for hydrogenation, and the at least one second metal species in monometallic form does not decompose hydrogen peroxide, wherein the combined amount of the first and second metal species is less than 15 wt. % of the catalyst, and wherein the catalyst comprises at least about 0.25 wt. % of the first metal, based on the total weight of the catalyst; or
- At least a portion of said hydrogen and oxygen or any solvent, for example, methanol, used in the direct synthesis is generated or regenerated or recycled from a by-product or waste stream of an industrial process, and/or
- the method is conducted in the presence of contaminated water, and/or (v) the method further comprises using the hydrogen peroxide produced in an industrial process, for example, as a bleaching agent.
- FIG. 1 shows the Temperature Programmed Reduction (TPR) profiles of monometallic Sn and Pd catalysts supported on ⁇ 2 and also a bare ⁇ 2 support after identical calcination treatment at 500°C for 3 hours.
- Figure 2 shows the TPR profile of various bimetallic catalysts of the invention supported on T1O2.
- Figure 3 shows XRD patterns of monometallic 5% Pd, 5% Sn and bimetallic 2.5% Pd 2.5% Sn catalysts supported on silica after calcination at 500 °C for 3 hours.
- Figure 4 shows a selection of XRD patterns for catalysts having variable Sn:Pd ratio.
- Figure 5 shows a selection of XRD patterns obtained in order to demonstrate that the absence of PdO peaks in Pd/Sn/Si02 catalysts was not due to the Pd being below the detection limits of the technique.
- Figure 6 shows the Pd(3d) XPS spectra of monometallic and bimetallic catalysts after calcination at 500 °C for 3 hours.
- Figure 7 shows the Pd(3d) XPS spectra for a 1 % Pd / 4% Sn / Si0 2 catalyst after calcination at 500 °C for 3 hours and subsequent reduction at various temperatures for 2 h under 5% H2 / Ar.
- Figure 8 shows the Pd(3d) spectra of a reduced 1 % Pd / 4% Sn / S1O2 catalyst after subsequent heat treatment at 400 °C in air for 2 hours and 3 hours.
- Figure 9 shows the Sn(3d 5 / 2 ) and Pd(3d) XPS spectra for a 3 % Pd / 2 % Sn / Ti0 2 catalyst following oxidation (O), oxidation and reduction (OR), oxidation-reduction- oxidation (ORO) and oxidation-reduction-oxidation-reduction-oxidation (ORORO).
- Figure 10 shows a combined microscopy (by STEM) and EDS analysis of a 3 % Pd / 2 % Sn / T1O2 catalyst following oxidation-reduction-oxidation (ORO) treatment cycle.
- Figure 1 1 is a STEM image showing a Pd-Sn-Ox nanoparticle partially embedded in the amorphous Sn0 2 layer formed on a highly ordered Ti0 2 support during ORO treatment of a 3 % Pd / 2 % Sn / Ti0 2 catalyst.
- the catalytic nanoparticles are formed during manufacture of the catalyst in which they ultimately reside, the catalyst being suitable for direct synthesis of hydrogen peroxide.
- the catalytic nanoparticles are an active species for hydrogen peroxide production via direct synthesis.
- the catalytic nanoparticles and, thus, the catalyst comprising same comprise at least two distinct metal species; a first metal species and at least one second metal species.
- the first and second metal species are different.
- a requisite characteristic of the first metal species is that, when in monometallic form, it has an activity for hydrogenation.
- the first metal species is selected from one or more of Pd, Pt, Ni, Ru, Rh, Os and Ir.
- the first metal species is selected from one or more of Pd, Pt and Ni.
- the first metal species is Pd or Pt or Ni. In certain embodiments, the first metal species is Pd. In certain embodiments, the first metal species forms, in addition to the catalytic nanoparticles, relatively smaller particles which are compositionally rich in the first metal species and substantially metallic, as may be determined by X-ray Photoelectron Spectroscopy (XPS). These relatively small particles may be up to about 5 nm in size, for example, up to about 3 nm in size, or up to about 2 nm in size, or up to about 1 nm in size, as may be determined, for example, using the STEM analysis methods described herein.
- XPS X-ray Photoelectron Spectroscopy
- a requisite characteristic of the second metal species is that, when in monometallic form, it does not decompose hydrogen peroxide. Additionally, it is desirable that the second metal species readily mixes with the first metal species to form a mixed oxide and/or alloy. Additionally, it is desirable that the second metal species is capable of forming an amorphous oxide layer on the surface of a catalyst support material during manufacture of the catalyst of the present invention and, more particularly, during the oxidation-reduction-oxidation treatment cycles by which the catalyst of the present invention may be manufactured. As described herein, the amorphous oxide layer may encapsulate the relatively smaller particles which are compositionally rich in the first metal species and substantially metallic.
- the at least one second metal species is selected from one or more of Ni, Zn, Sn, In, Ge, Ga, Cu, Fe, Co, Cr, Mo and W. In certain embodiments, the at least one second metal is selected from one or more of Ni, Zn and Sn, for example, Ni and Zn, Ni and Sn, or Sn and Zn. In certain embodiments, the at least one second metal is Ni (i.e., Ni is the sole second metal species). In certain embodiments, the at least one second metal is Zn. In certain embodiments, the at least one second metal is Sn. In certain embodiments, if the catalyst nanoparticle comprises only one second metal species, the second metal species is other than Sn.
- the reference to 'monometallic form does not mean that the metal species is/are in monometallic form when present in the catalytic nanoparticles and catalysts.
- the metal species is/are in monometallic form when present in the catalytic nanoparticles and catalysts.
- the first metal species is Pd and the second metal species is one or more of Ni, Zn and Sn, or a combination of Sn and one or more of Ni, Zn, In, Ge, Ga, Cu, Fe, Co and Cr.
- the first metal species is Pd and the second metal species is Sn.
- the first metal species is Pd and the second metal species is Ni.
- the first metal species is Pd and the second metal species is Zn.
- the first and second metal species both have an assigned oxidation number (i.e., oxidation state) which is a positive number, for example, 1 +, 2+, 3+, 4+, etc, as may be determined by XPS (based on the Auger parameter).
- the actual oxidation state of the first and/or second metal species may vary from the assigned oxidation number, as may be determined by XPS. This may indicate a degree of electronic interaction between the metal species in the catalytic nanoparticle.
- the oxidation state of the first and metal species shifts (e.g., by up to about +/- 0.5 eV) following the oxidation-reduction- oxidation treatment cycle for manufacturing the catalyst nanoparticles and catalyst comprising same.
- the first and second metal species are present in the catalytic nanoparticle as a mixed metal oxide, alloy or both.
- the second metal species acts, in part, as a spacer at the surface of the catalyst nanoparticle, enabling better access to surface active sites for the hydrogen and oxygen species and subsequent formation of hydrogen peroxide.
- the catalytic nanoparticles are up to about 10 nm in size, for example, from about 2 nm to about 10 nm in size, as may be determined by any suitable scanning transmission electron microscopy (STEM) method, for example, STEM analysis performed on a JEOL 2200FS STEM equipped with a CEOS probe corrector and Thermo-Noran X-ray energy dispersive spectroscopy (XEDS) system.
- STEM scanning transmission electron microscopy
- the catalytic nanoparticles are from about 2 nm to about 8 nm in size, or from about 2 nm to about 6 nm, or from about 2.5 nm to about 5 nm, or from about 2.5 nm to about 4 nm.
- the catalytic nanoparticles form during manufacture of the catalyst in which the catalytic nanoparticles ultimately reside following manufacture of the catalyst.
- the catalyst comprises a catalyst support (e.g., a crystalline titania or silica support material) with catalytic nanoparticles at or on the surface of the support.
- a catalyst support e.g., a crystalline titania or silica support material
- an amorphous oxide layer of which at least a portion is an oxide of the at least one second metal species, forms on the catalyst support, and catalytic nanoparticles are present on or in the amorphous oxide layer.
- at least a portion of the catalytic nanoparticles are partially embedded or partially encapsulated in the amorphous layer.
- the amorphous oxide layer may serve to anchor the catalyst particles to the support, leaving a surface of the catalyst nanoparticle exposed and available to catalyse the direct synthesis of hydrogen peroxide from hydrogen and oxygen.
- the amorphous oxide layer serves to wholly encapsulate the relatively smaller particles which are compositionally rich in the first metal species and substantially metallic, thereby suppressing the hydrogenation activity of theses metal rich species which would otherwise hydrogenate hydrogen peroxide.
- the thickness of the amorphous oxide may vary. For example, it may up to about 5 nm thick, or up to about 4 nm thick, or up to about 3 nm thick, or up to about 2 nm thick, or up to about 1 nm thick, as may be determined by STEM analysis.
- the amorphous oxide layer may be seen as 'fuzzy' layer proximate a highly ordered support material (e.g., T1O2). It may form as a continuous layer upon the surface of the support. In certain embodiments, if may form as a discontinuous layer, by which is meant that 'islands' of the amorphous oxide layer form upon the surface of the support and that there are areas of the support surface which have no amorphous layer formed thereon.
- a highly ordered support material e.g., T1O2
- the catalyst of the present invention may also be characterised compositionally.
- the catalyst for direct synthesis of hydrogen peroxide comprises a first metal species and at least one second metal species, wherein the first metal species in monometallic form has an activity for hydrogenation, and the at least one second metal species in monometallic form does not decompose hydrogen peroxide, wherein the combined amount of the first and second metal species is less than 15 wt. % of the catalyst, and wherein the catalyst comprises at least about 0.10 wt. % of the first metal species, for example, at least about 25 wt. % of the first metal species, based on the total weight of the catalyst.
- the catalyst comprises only one second metal species, it is other than tin, i.e., the catalyst is free of tin.
- the catalyst comprises catalytic nanoparticles, as described herein.
- the combined amount of the first and second metal species is less than about 14 wt % of the catalyst, for example, less than about 13 wt. % of the catalyst, or less than about 12 wt. % of the catalyst, or less than about 1 1 wt. % of the catalyst, or less than about 10 wt. % of the catalyst, or less than about 9.0 wt. % of the catalyst, or less than about 8.0 wt. % of the catalyst, or less than about 7.0 wt. % of the catalyst, or less than about 6.0 wt. % of the catalyst.
- the combined amount of the first and second metal species is at least about 0.5 wt. % of the catalyst, optionally subject to the proviso that the catalyst comprises at least about 0.25 wt. % of the first metal species.
- the combined amount of the first and second metal species is at least about 0.75 wt. % of the catalyst, for example, at least about 1.0 wt. % of the catalyst, or at least about 1.5 wt. % of the catalyst, or at least about 2 wt. % of the catalyst, or at least about 2.5 wt. % of the catalyst, or at least about 3 wt. % of the catalyst, or at least about 4 wt. % of the catalyst.
- the combined amount of the first and second metal species constitutes from about 0.5 to less than 15 wt. % of the catalyst, for example, from about 1.0 to about 12 wt. % of the catalyst, or from about 2.0 to about 10 wt.
- weight ratio of the first metal species to the second metal species is from about 8: 1 to about 1 :8, for example, from about 6: 1 to about 1 :6, or from about 5: 1 to about 1 :5, or from about 4: 1 to about 1 :4, or from about 3: 1 to about 1 :3, or from about 2:1 to about 1 :2, or from about 1.5: 1 to about 1 : 1.5, or about 1 : 1.
- the catalyst is a bimetallic catalyst comprising Pd (as first metal species) and Sn (as second metal species), with the proviso that the catalyst comprises at least about 0.25 wt. % Pd.
- the combined amount of Pd and Sn is less than about 14 wt % of the catalyst, for example, less than about 13 wt. % of the catalyst, or less than about 12 wt. % of the catalyst, or less than about 12 wt. % of the catalyst, or less than about 1 1 wt. % of the catalyst, or less than about 10 wt. % of the catalyst, or less than about 9.0 wt. % of the catalyst, or less than about 8.0 wt. % of the catalyst, or less than about 7.0 wt. % of the catalyst, or less than about 6.0 wt. % of the catalyst.
- the combined amount of Pd and Sn is at least about 0.5 wt. % of the catalyst, subject to the proviso that the catalyst comprises at least about 0.25 wt. % of Pd. In certain embodiments, the combined amount of Pd and Sn is at least about 0.75 wt. % of the catalyst, for example, at least about 1.0 wt. % of the catalyst, or at least about 1.5 wt. % of the catalyst, or at least about 2 wt. % of the catalyst, or at least about 2.5 wt. % of the catalyst, or at least about 3 wt. % of the catalyst, or at least about 4 wt. % of the catalyst.
- the combined amount of Pd and Sn comprises from about 0.5 to less than 15 wt. % of the catalyst, for example, from about 1.0 to about 12 wt. % of the catalyst, or from about 2.0 to about 10 wt. % of the catalyst, or from about 3.0 to about 8 wt. % of the catalyst, or from about 4.0 to about 7 wt.% of the catalyst, or from about 4.0 to about 6.0 wt. % of the catalyst.
- weight ratio of Pd to Sn is from about 8:1 to about 1 :8, for example, from about 6: 1 to about 1 :6, or from about 5: 1 to about 1 :5, or from about 4: 1 to about 1 :4, or from about 3: 1 to about 1 :3, or from about 2:1 to about 1 :2, or from about 1.5: 1 to about 1 : 1.5, or about 1 : 1.
- the catalyst comprises from about 0.5 wt.% to about 12 wt. % Sn and from about 0.25 wt. % to about 6 wt. % Pd, for example, from about 0.5 wt. % to about 8 wt. % Sn and from about 0.5 wt.
- the catalyst comprises from about 2.0 wt. % to about 6.0 wt. % Pd and from about 0.5 wt. % to about 3 wt. % Sn, for example, from about 3.0 wt. % to about 5.0 wt. % Pd and from about 0.5 wt. % to about 2.0 wt. % Sn. In certain embodiments, the catalyst comprises about 4 % Pd and about 1 wt.
- % Sn or about 3 wt. % Pd and about 2 wt. % Sn, or about 2 wt. % Pd and about 3 wt. % Sn, or about 1 wt. % Pd and about 2 wt. % Sn, based on the total weight of the catalyst.
- the catalyst is a bimetallic catalyst comprising Pd (as first metal species) and Ni or Zn (as second metal species), optionally with the proviso that the catalyst comprises at least about 0.10 wt. % Pd, for example, at least about 0.20 wt. % Pd, or at least about 0.25 wt. % Pd.
- the second metal is referred to as Ni.
- the amounts and relative amounts described apply equally to embodiments in which the second metal species is Zn.
- the combined amount of Pd and Ni is less than about 14 wt % of the catalyst, for example, less than about 13 wt. % of the catalyst, or less than about 12 wt.
- the catalyst or less than about 12 wt. % of the catalyst, or less than about 1 1 wt. % of the catalyst, or less than about 10 wt. % of the catalyst, or less than about 9.0 wt. % of the catalyst, or less than about 8.0 wt. % of the catalyst, or less than about 7.0 wt. % of the catalyst, or less than about 6.0 wt. % of the catalyst.
- the combined amount of Pd and Ni is at least about 0.5 wt. % of the catalyst, optionally subject to the proviso that the catalyst comprises at least about 0.10 wt. % Pd, for example, at least about 0.20 wt. % Pd, or at least about 0.25 wt. % Pd 0.25 wt. % of palladium.
- the combined amount of Pd and Ni is at least about 0.75 wt. % of the catalyst, for example, at least about 1.0 wt. % of the catalyst, or at least about 1.5 wt. % of the catalyst, or at least about 2 wt. % of the catalyst, or at least about 2.5 wt.
- the combined amount of Pd and Ni constitutes from about 0.5 to less than 15 wt. % of the catalyst, for example, from about 1.0 to about 12 wt. % of the catalyst, or from about 2.0 to about 10 wt. % of the catalyst, or from about 3.0 to about 8 wt. % of the catalyst, or from about 4.0 to about 7 wt.% of the catalyst, or from about 4.0 to about 6.0 wt. % of the catalyst.
- the weight ratio of Pd to Ni is from about 8:1 to about 1 :8, for example, from about 6: 1 to about 1 :6, or from about 5: 1 to about 1 :5, or from about 4: 1 to about 1 :4, or from about 3: 1 to about 1 :3, or from about 2: 1 to about 1 :2, or from about 1.5: 1 to about 1 : 1.5, or about 1 : 1.
- the catalyst comprises from about 0.1 wt.% to about 2 wt. % Pd and from about 0.5 wt. % to about 10 wt. % Ni, for example, from about 0.2 wt. % to about 1.5 wt. % Pd and from about 0.5 wt.
- % to about 7.5 wt. % Ni or from about 0.25 wt. % to about 1 wt. % Pd and from about 1.0 wt. % to about 5.0 wt. % Ni, or from about 0.25 wt. % to about 1 wt. % Pd and from about 2.0 wt. % to about 5.0 wt. % Ni, or from about 0.25 wt. % to about 1 wt. % Pd and from about 3.0 wt. % to about 5.0 wt. % Ni, based on the total weight of the catalyst.
- the catalyst support is an organic or inorganic support, for example, catalyst support selected from the group consisting of carbon supports, oxide supports and silicate supports, for example, from S1O2, ⁇ 2, AI2O3, CeC>2, Nb20s, W2O3, ZrC>2, Fe2C>3, silica-alumina, molecular sieves and zeolites, and mixtures thereof.
- Suitable carbon supports are graphite, carbon black, glassy carbon, activated carbon, highly orientated pyrolytic graphite, single-walled and multi-walled carbon nanotubes.
- the catalyst support comprises or is an oxide support, for example, an oxide support selected from S1O2, ⁇ 2, AI2O3, CeC>2, Nb20s, W2O3, ZrC>2, Fe2C>3 and mixtures thereof.
- the catalyst support is an acidic catalyst support.
- Acidic catalyst supports include, for example, niobic acid support, heteropolyacid-based support, acid-treated carbon support, sulfated zirconia/silica support, and a support comprising an oxide other than zirconium oxide (e.g., silica) and a precipitate layer of zirconium oxide.
- Heteropolyacid supports include supports of the formula Cs x H3- x PWi204o, where x is from about 2.0 to about 2.9, which may be prepared by the addition of a Cs source, such as CsNC , to aqueous H3PW12O40.
- the catalyst support comprises or is S1O2.
- the catalyst support comprises or is ⁇ 2.
- the catalyst support comprises a mixture of S1O2 and ⁇ 2.
- the catalyst does not comprise carbon supports.
- the catalyst support may comprise at least about 60 wt. % of the catalyst, based on the total weight of the catalyst, for example, at least about 70 wt. % of the catalyst, or at least about 80 wt.
- the catalyst support comprises from about 60 wt. % to about 99 wt. % of the catalyst, for example, from about 70 wt. % to about 99 wt. % of the catalyst, or from about 80 wt. % to about 97 wt. % of the catalyst, or from about 85 wt. % to about 95 wt. % of the catalyst, or from about 90 wt. % to about 95 wt. % of the catalyst.
- the catalyst is a bimetallic catalyst comprising Pd and Sn and the catalyst support comprises or is S1O2.
- the catalyst comprises from about 0.25 wt. % to about 3.0 wt. % Pd and from about 2.0 wt. % to about 6.0 wt. % Sn, for example, from about 0.5 to about 2.0 wt. % Pd and from about 3.0 wt. % to about 5.0 wt. Sn, or from about 0.75 wt. % to about 1.25 wt. Pd and from about 3.5 wt. % to about 4.5 wt.% Sn, or about 1 wt.% Pd and about 4 wt. % Sn.
- the catalyst is a bimetallic catalyst comprising Pd and Sn and the catalyst support comprises or is ⁇ 2.
- the catalyst comprises from about 1.5 wt. % to about 5 wt. % Pd and from about 0.25 wt. % to about 4.0 wt. % Sn, for example, from about 2.0 wt. % to about 4.0 wt. % Pd and from about 1.0 wt. % to about 3.0 wt. % Sn, or from about 2.5 wt.% to about 3.5 wt. % Pd and from about 1. 5 wt. % to about 2.5 wt. % Sn, or about 3 wt. % Pd and about 2 wt. % Sn.
- the catalyst is a bimetallic catalyst comprising Pd and Ni and the catalyst support comprises or is ⁇ 2.
- the catalyst comprises from about 0.10 wt. % to about 2.5 wt. % Pd and from about 0.50 wt. % to about 6.0 wt. % Ni, for example, from about 0.25 wt. % to about 2.0 wt. % Pd and from about 1.0 wt. % to about 5.0 wt. % Ni, or from about 0.25 wt.% to about 1.5 wt. % Pd and from about 2.0 wt. % to about 5.0 wt. % Ni, or from about 0.25 wt. % to about 1.0 wt.
- the catalyst is a bimetallic catalyst comprising Pd and Zn and the catalyst support comprises or is ⁇ 2.
- the catalyst comprises from about 0.10 wt. % to about 2.5 wt. % Pd and from about 0.50 wt. % to about 6.0 wt. % Ni, for example, from about 0.25 wt. % to about 2.0 wt. % Pd and from about 1.0 wt. % to about 5.0 wt.
- the catalyst of the invention may be characterised in terms of one or more properties, such as a Temperature Programmed Reduction (TPR) profile or X-ray powder diffraction pattern (XRPD).
- TPR Temperature Programmed Reduction
- XRPD X-ray powder diffraction pattern
- references to known X-ray powder diffraction patterns means, unless otherwise stated, the X-ray powder diffraction as according to the International Centre for Diffraction Data (ICDD) database (www.icdd.com).
- ICDD International Centre for Diffraction Data
- the ICDD meets the requirements of standard ISO 9001 :2008 pertaining to centralized assembling, recording, designing, editing and publishing of diffraction data for use by scientists worldwide and providing technical forums for promoting diffraction and related materials analysis techniques in science and technology.
- the catalyst has a TPR profile, as determined in accordance with the method described herein, characterised by the presence of a relatively broad, positive peak (mV) between about 140°C and 200°C, for example, between about 150 °C and about 180 °C.
- said catalyst comprises from about 0.5 wt. % to about 5 wt. % Pd, and from about 0.5 wt. % to about 5 wt. % Sn.
- a TPR profile of an exemplary catalyst of the invention is depicted Figure 2.
- the catalyst has a powder X-ray diffraction pattern, as determined in accordance with the method described herein, characterised by the absence of any discernable peaks (2 ⁇ ) attributable to Pd-containing or Sn-containing species above the S1O2 support diffraction pattern, for example, the absence of any discernable peak at 34° ⁇ 0.5 2 ⁇ attributable to Pd-containing or Sn-containing species, e.g. PdO or SnO as according to the ICCD database.
- the catalytic nanoparticles, and the catalyst comprising same are in certain embodiments manufactured by a process comprising (i) preparing, providing or obtaining a catalyst precursor comprising catalyst support, a first metal species and at least one second metal species, wherein the first metal species in monometallic form has an activity for hydrogenation, and the at least one second metal species in monometallic form does not decompose hydrogen peroxide, (ii) treating the catalyst precursor under oxidizing conditions in a first step, (iii) treating the oxidised catalyst under reducing conditions in a second step, and (iv) treating the reduced catalyst under oxidising conditions at an elevated temperature (e.g., at a temperature higher than that which would be employed in the manufacture of hydrogen peroxide by direct synthesis, for example, an elevated temperature which is at least about 150 °C) in a third step.
- an elevated temperature e.g., at a temperature higher than that which would be employed in the manufacture of hydrogen peroxide by direct synthesis, for example, an elevated temperature which is
- the second metal species is other than tin.
- this oxidation-reduction- oxidation treatment cycle (sometimes referred to herein as 'O-R-0 or 'ORO') serves to "lock-in" the favourable catalytic activity of the catalyst of the present invention, promoting activity for production of hydrogen peroxide and suppressing or even eliminating subsequent hydrogenation of hydrogen peroxide.
- the catalyst precursor of step (i) may be prepared by any suitable preparative method, preferably starting from suitable metal precursors.
- the first and second metal species as catalytically active components, may be deposited onto a catalyst support in the form of metal oxides or metal ions, e.g., metal salt (i.e., nitrate, chloride, and the like), by any known method to form a catalyst precursor.
- the first and second metal species may be deposited simultaneously or sequentially, advantageously simultaneously.
- a catalyst precursor may be recovered by any suitable separation method, such as evaporation, filtration, decantation and/or centrifugation.
- the recovered catalyst precursor may be washed and dried, for example, at a temperature of between about 50 °C and 150°C, typically greater than about 100°C, for example, greater than about 105°C, and typically, less than about 130 °C, for example, less than about 120 °C, e.g., a temperature of from about 105 °C to about 1 15 °C.
- Drying may be conducted over a suitable period of time, for example, up to about 24 hours, for example, from about 8 to 20 hours, or from about 12 to about 20 hours, or from about 12 to about 20 hours, or from about 14 to about 20 hours, or from about 12 to 18 hours, or from about 15 to about 17 hours.
- the step of preparing, providing or obtaining a catalyst precursor comprising first and second metal species comprises depositing the first and second metal species onto the catalyst support in form of first metal/second metal oxides or first and second metal ions, for example, using a first metal salt and second metal salt, e.g., a Sn(IV) salt or a Sn(ll) salt, preferably a Sn(IV) salt).
- a first metal salt and second metal salt e.g., a Sn(IV) salt or a Sn(ll) salt, preferably a Sn(IV) salt.
- Exemplary salts include the nitrate or chloride or sulphate or carbonate.
- the salt is a chloride or nitrate, e.g., SnCI 4 .xH 2 0, NiCI 2 .xH 2 0, ZnCI 2 .xH 2 0 and Pd (N0 3 ) 2 .xH 2 0, wherein x is from 1 to 6, for example, SnCI 4 .5H 2 0, NiCI 2 .6H 2 0 and Pd(N0 3 ) 2 .2H 2 0.
- the first and second metal may be deposited simultaneously or sequentially, advantageously simultaneously on the catalyst support. For example, an aqueous solution of the first metal salt and the second metal may be prepared, followed by addition of the catalyst support.
- the relative amounts and weight ratios of first metal species, second metal species and catalyst support may be selected accordingly in order to obtain a catalyst having the desired catalyst support and relative amounts of first and second metal.
- the catalyst precursor composition is recovered by any suitable separation method, such as evaporation, filtration, decantation and/or centrifugation.
- the recovered catalyst precursor may be washed and dried, for example, at a temperature of between about 50 °C and 150°C, typically greater than about 100°C, for example, greater than about 105°C, and typically, less than about 130 °C, for example, less than about 120 °C, e.g., a temperature of from about 105 °C to about 1 15 °C.
- Drying may be conducted over a suitable period of time, for example, up to about 24 hours, for example, from about 8 to 20 hours, or from about 12 to about 20 hours, or from about 12 to about 20 hours, or from about 14 to about 20 hours, or from about 12 to 18 hours, or from about 15 to about 17 hours.
- the catalyst precursor is then transformed into the corresponding catalyst, generating the hereinbefore described catalytic nanoparticles, via the treatment cycle according to (ii), (iii) and (iv) above.
- the treatment cycle is conducted at elevated temperatures, for example, each of (ii), (iii) and (iv) are conducted at a temperature of at least about 175 °C, or at least about 200 °C.
- the O-R-0 treatment cycle may be conducted under any suitable atmosphere such as, for example, oxygen containing atmosphere, inert atmosphere or reducing atmosphere.
- the treatment may be conducted under air, oxygen, nitrogen, argon, hydrogen or mixtures thereof.
- oxidising step (i) is conducted at a temperature of from about 250 °C to about 800 °C, for example, from about 300 °C to about 700°C, or from about 350 °C to about 600°C, or from about 400 °C to about 550 °C, or from about 450 °C to about 550 °C, or from about 475 °C to about 525°C.
- the salt precursor will decompose at such temperatures.
- Heat treatment may be conducted under any suitable type of atmosphere such as, for example, oxygen containing atmosphere or inert atmosphere. In certain embodiments, the heat treatment is conducted under air, oxygen, nitrogen, argon, or mixtures thereof.
- the heat treatment leads to the formation of an second metal-first metal(ll) alloy in a mixed oxide type material and/or first metal(ll) oxide which is contact with the second metal oxide.
- the oxidation state of the first and second metal species be determined by chemical analysis such as XPS.
- Step (ii) may be considered an oxidation step as both the first and second metal species become associated with oxygen.
- Treatment step (ii) may be conducted for a period of time ranging from about 30 mins to about 10 hours, for example, from about 1 hour to about 8 hours, or from about 2 hours to about 6 hours, or from about 2 hours to about 5 hours, or from about 2 hours to about 4 hours, or from about 2.5 hours to about 3.5 hours, or about 3 hours.
- step (ii) comprises or consists of oxidising the catalyst precursor at a temperature of from about 450 °C to about 550 °C for a period of from about 2 to about 4 hours.
- the oxidized catalyst is treated under reducing conditions, forming a reduced catalyst.
- chemical analysis such as XPS, may indicate the presence of a metallic first metal species, which STEM analysis indicates is in the form of relatively smaller nanoparticles which are compositionally rich in the first metal species and substantially metallic.
- the reducing treatment in some embodiments, have the effect of reducing the H2O2 productivity of the catalyst during direct synthesis. However, any modest decrease in H2O2 productivity is advantageously off-set by the increased stability and re-usability of the catalyst.
- Reducing conditions include heat treatment under reducing conditions, chemical reduction and electrodeposition.
- the oxidized catalyst from step (ii) is heat treated under reducing conditions, for example, a mixture of hydrogen and an inert gas such as argon or nitrogen, and at an elevated temperature of at least about 50 °C and for a period of time of from about 30 minutes to about 10 hours, for example, from about 30 minutes to about 8 hours, or from about 1 hour to about 6 hours, or from about 1 hour to about 4 hours, or from about 1 hour to about 3 hours, or from about 1.5 hours to about 2.5 hours, or about 2 hours.
- reducing conditions for example, a mixture of hydrogen and an inert gas such as argon or nitrogen
- the temperature is from about 50 °C to about 350 °C, for example, from about 75°C to about 300°C, or from about 75 °C to about 275 °C, or from about 75 °C to about 250°C, or from about 100°C to about 300°C, or from about 150 °C to about 250 °C, or from about 175 °C to about 225 °C.
- the mixture of hydrogen and argon may comprise up to about 20 vol. % hydrogen, for example, up to about 15 vol. % hydrogen, or up to about 10 vol. % hydrogen, or up to about 8 vol. % hydrogen, or up to about 6 vol. % hydrogen, or up to about 5 vol. % hydrogen.
- the mixture may comprise less than 5 vol. % hydrogen.
- step (iii) comprises or consists of heat treating the heat-treated catalyst from step (ii) under a mixture of hydrogen and argon at a temperature from about 150 °C to about 250 °C for a period of time of from about 1 to about 3 hours.
- the mixture of hydrogen and argon may comprise up to about 10 vol. % hydrogen, for example, up to about 8 vol. % hydrogen, or up to about 6 vol. % hydrogen, or up to about vol. 5 % hydrogen.
- Chemical reducing agents are known in the art and may be selected, for example, from NaH, LiH, LiAlhU, NaBhU, KBH4, Cahb, SnC , diisobutylaluminium hydride, sodium citrate, disodium citrate, trisodium citrate, sodium formate, formic acid, hydrazine, methanol, and combinations thereof.
- Other reducing treatments include, for example, radiolysis in the presence of isopropanol.
- the reduced catalyst is treated under oxidizing conditions.
- treating the reduced (and initially heat-treated) catalyst under oxidizing conditions may significantly suppress, or even completely inhibit, hydrogen peroxide hydrogenation and decomposition activity, without adversely affecting the stability of the catalyst.
- this further treatment results in the formation/build-up of a substantially amorphous layer of an oxide of the second metal species, which resides on the catalyst support and which encapsulates, in some embodiments, wholly, the relatively smaller nanoparticles described above which are compositionally rich in the first metal species and substantially metallic.
- the oxidizing conditions of step (iv) may comprise or consist of heating the reduced catalyst in an oxidizing atmosphere at an elevated temperature.
- the reduced catalyst may be heated in oxygen, air or an atmosphere comprising higher levels of oxygen relative to air.
- the temperature may be from about 250 °C to about 800 °C, for example, from about 300 °C to about 700°C, or from about 350 °C to about 600°C, or from about 350 °C to about 550 °C, or from about 350 °C to about 500 °C, or from about 350 °C to about 450°C, or from about 375 °C to about 425 °C, or about 400 °C.
- the heat treatment may be conducted for a period of time ranging from about 30 mins to about 10 hours, for example, from about 1 hour to about 8 hours, or from about 2 hours to about 6 hours, or from about 2 hours to about 5 hours, or from about 3 hours to about 5 hours, or from about 3.5 hours to about 4.5 hours, or about 4 hours.
- step (iv) comprises or consists of heating the reduced catalyst in air at temperature of from about 350 °C to about 450 °C for a period of time of from about 2 hours to about 4 hours or from about 3 hours to about 5 hours.
- the period of time is from about 2 hours to about 4 hours, for example, 2.5 hours to about 3.5 hour, or no more than about 3 hours.
- the support is T1O2
- the period of time is from about 3 hour to about 5 hours, for example, from about 3.5 hours to about 4.5 hours, or no more than about 4 hours.
- the oxidizing conditions may comprise chemical oxidation, for example, oxidation of the reduced catalyst in the presence of chemical oxidizing agents such as, for example, perchloric acid, H2O2 and/or N2O.
- the catalyst may be subjected to further reduction and oxidation treatment steps.
- an O-R-0 may be followed by a subsequent reduction and oxidation step, i.e., and O-R-O-R-0 treatment cycle, and so on.
- the conditions of any subsequent reduction and oxidation treatment steps may be the same as those described in connection with steps (ii), (iii) and (iv) above.
- the catalyst of the invention is obtainable or prepared by a process comprising: (i) depositing (optionally simultaneously) a first metal species and second metal species onto a catalyst support by co-impregnation, forming a catalyst precursor comprising catalyst support, first and second metal, (ii) oxidizing the catalyst precursor at a temperature of from about 450 °C to about 550 °C for a period of from about 2 hours to about 4 hours, forming an oxidized catalyst catalyst, (iii) treating the oxidized catalyst of step (ii) under a mixture of hydrogen and argon at a temperature of from about 150 °C to about 250 °C for a period of time of from about 1 hour to about 3 hours, forming a reduced catalyst, and (iv) treating the reduced catalyst of step (iii) under oxidising conditions by heating the reduced catalyst in air at a temperature of from about 350 °C to about 450 °C, or from 450 °C to 550 °C, for a period
- the catalyst of the invention may be re-usable without major reduction in H2O2 productivity. This indicates the catalyst is stable.
- the stability of a catalyst of the invention may be determined by comparing its H2O2 productivity on first use in a direct synthesis reaction and its H2O2 productivity on second use in a direct synthesis reaction (the conditions of the first and second direct synthesis reaction are identical). H2O2 productivity is determined in accordance with the method and calculations described in the Examples below.
- the catalyst has a stability of at least about 60 %, which is calculated as [(H2O2 productivity on second use)/(H2C>2 productivity on first use) x 100].
- the catalyst has a stability of at least about 70 %, for example, at least about 80 %, or at least about 85 %, or at least about 90 %, or at least about 92 %, or at least about 94 %, or at least about 96 %, or at least about 98 %, or at least about 99 %.
- the catalyst may have a stability of 100 %, indicating no loss in H2O2 productivity between first and second use of the catalyst in a direct synthesis reaction.
- the catalyst support may be S1O2 or Ti0 2 . Direct synthesis of hydrogen peroxide, H2O2
- the process of manufacturing hydrogen peroxide by direct synthesis comprises converting hydrogen and oxygen to hydrogen peroxide in the presence of a catalyst of the invention, i.e., a catalyst according to the first and second aspects of the invention.
- the catalyst is heterogeneous. It has been surprisingly found that reacting hydrogen and oxygen in the presence of a catalyst of the invention enables the preparation of hydrogen peroxide with an increased productivity and/or suppressed hydrogenation activity and/or increased selectivity to hydrogen peroxide. Indeed, in certain embodiments, it is possible to suppress or even completely inhibit hydrogenation and decomposition of hydrogen peroxide.
- catalytic nanoparticles comprising a mixed metal oxide and/or alloy of a first metal and at least one second metal, wherein the first metal in monometallic form has an activity for hydrogenation, and the at least one second metal in monometallic form does not decompose hydrogen peroxide; or
- a catalyst comprising a first metal species and at least one second metal species, wherein the first metal species in monometallic form has an activity for hydrogenation, and the at least one second metal species in monometallic form does not decompose hydrogen peroxide, wherein the combined amount of the first and second metal species is less than 15 wt. % of the catalyst, and wherein the catalyst comprises at least about 0.25 wt. % of the first metal, based on the total weight of the catalyst; or
- At least a portion of said hydrogen and oxygen or any solvent, for example, methanol, used in the direct synthesis is generated or regenerated or recycled from a by-product waste stream of an industrial process, and/or
- At least a portion of said hydrogen is generated from the electrolysis of water, and/or
- the method is conducted in the presence of contaminated water, and/or
- the method further comprises using the hydrogen peroxide
- the direct synthesis process may be conducted in any type of suitable reactor known in the art, for example, a stirred reactor, such as an autoclave equipped with stirring means, a loop reactor or a tube reactor.
- a stirred reactor such as an autoclave equipped with stirring means, a loop reactor or a tube reactor.
- the process may be conducted batchwise, continuously or semi-continuously.
- the catalyst may be in the reactor as a fixed bed or fluidized bed.
- the direct synthesis process is conducted at a temperature of from about -20 °C to about 100 °C, for example, from about -10 °C, to about 80 °C, or from about -5 °C to about 50 °C, or from about -2 °C to about 25 °C, or from about -1 °C to about 10 °C, or from about 0 °C to about 10°C, or from about 1 °C to about 50 °C, or from about 1 °C to about 25 °C, or from about 1 °C to about 10 °C, or from about 1 °C to about 5 °C, or from about 1 °C to about 3 °C, or at a temperature of about 0°C, or about 1 °C, or about 2 °C, or about 3 °C, or about 4 °C.
- the direct synthesis process is conducted at a temperature of from about 10 °C to about 30 °C, for example, from about 15 °C to about 25 °C, or a temperature of about 20 °C.
- the process is conducted in a liquid medium, for example, an aqueous liquid medium.
- the aqueous medium may comprise a water-miscible solvent including, for example, methanol, ethanol, isopropyl alcohol, acetone and glycols such as ethylene glycol, propylene glycol, diethylene glycol and dipropylene glycol, and mixtures thereof.
- the liquid medium is aqueous methanol.
- the weight ratio of water-miscible solvent to water is from about 10: 1 to about 1 : 10, for example, from about 8: 1 to about 1 :8, or from about 5: 1 to about 1 :5, or from about 4: 1 to about 1 :4, or from about 4: 1 to about 1 :2, or from about 4: 1 to about 1 : 1 , or from about 3: 1 to about 1 : 1 , or from about 2: 1 to about 1 : 1.
- the total pressure in the reactor may vary according to the reaction conditions, amounts of starting materials and the type of reactor. In certain embodiments, the total pressure in the reactor is from about 0.1 to about 15 MPa, for example, from about 0.5 to about 10 MPa, or from about 1 to about 8 MPa, or from about 2 to about 6 MPa, or from about 3 to about 5 MPa, or from about 3.5 to about 4.5 MPa, or about 4 MPa.
- the reaction time may vary according to the reaction conditions and amounts of starting materials and may be adjusted accordingly.
- the reaction time is from about 30 seconds to about 10 hours, for example, from about 1 minute to about 5 hours, or from about 5 minutes to 300 minutes, or from about 10 minutes to about 240 minutes, or form about 10 minutes to about 180 minutes, or from about 15 minutes to about 120 minutes, or from about 15 minutes to about 90 minutes, or from about 15 minutes to about 60 minutes, or from about 15 minutes to about 45 minutes, or from about 20 minutes to about 60 minutes, or from about 25 minutes to about 50 minutes, or from about 25 minutes to about 40 minutes.
- the reaction medium additionally comprises other components which further enhance the direct synthesis process.
- halides and acids may be added to suppress the competing hydrogenation and decomposition reactions leading to improved yields of H2O2.
- bromide ions e.g., in the form of hydrogen bromide
- inorganic acid may be added to stabilize the hydrogen peroxide formed.
- Exemplary inorganic acids are sulphuric acid, nitric acid, hydrochloric acid and ortho-phosphoric acid.
- the process of manufacturing hydrogen peroxide by direct synthesis is conducted in the absence of halide and/or acid stabilizers.
- At least a portion of one of said hydrogen and oxygen or any solvent is derived from an industrial process.
- at least a portion of said hydrogen and oxygen or any solvent, for example, methanol, used in the direct synthesis is generated or regenerated or recycled from a by-product or waste stream of an industrial process.
- method further comprises using the hydrogen peroxide produced in an industrial process, for example, as a bleaching agent, disinfectant, or reagent in a chemical process.
- the industrial process may be an integrated process in which a reagent of the direct synthesis process, for example, hydrogen and/or methanol, is generated from a by-product or waste stream and used as a feed to the direct synthesis method along with oxygen, and the catalyst of the invention is used to generate hydrogen peroxide which, in turn, is used in the industrial process from which the by-product or waste stream is produced.
- At least a portion of the hydrogen (and optionally oxygen) used in the direct synthesis is generated from the electrolysis of water.
- the method is conducted in the presence of contaminated water, i.e., using contaminated water as solvent, optionally in conjunction with other solvents, such as clean water and/or methanol.
- contaminated water may be contaminated with bacteria, which would be eradicated under the reaction conditions of the direct synthesis method, thereby producing a de-contaminated water in addition to hydrogen peroxide.
- the catalyst of the invention may also be used for the synthesis of hydrogen peroxide by indirect methods, such as by the anthraquinone process.
- tin and palladium monometallic and bimetallic catalysts were prepared by impregnating or co-impregnating aqueous solutions of metal salts onto the appropriate catalyst support which included ⁇ 2 and S1O2.
- the catalysts prepared had a nominal total metal loading of 5 wt% unless otherwise stated.
- a typical preparation for 1 g of 2.5 % Pd / 2.5% Sn / ⁇ 2 was carried out as follows: 0.063 g Pd(N03)2.2H20 was first dissolved in 2 ml of de-ionised water and heated to 80 °C with stirring.
- a typical preparation for 1 g of 2.5% Pd / 2.5% Au / ⁇ 2 was carried out according to the following procedure: 0.042 g of PdCl2 was added to 2.04 ml of HAuCU (12.25 g Au / 1000 ml) and heated to 80 °C with stirring and left until the PdCl2 had completely dissolved. 0.95 g of the desired support was then added to the solution and the water allowed to evaporate until the mixture formed a paste like consistency. The samples were dried at 1 10 °C for 16 h and then calcined in static air at various temperatures, typically 400 °C for 3 h with a ramp rate of 20 °C min 1 .
- each catalyst for the direct synthesis of H2O2 from H 2 and O2 was determined using a Parr Instruments stainless-steel autoclave (equipped with an overhead stirrer and temperature/pressure sensors) with a nominal volume of 100 ml and a maximum working pressure of 14 MPa.
- the autoclave was charged with 5.6 g of MeOH, 2.9 g of HPLC grade H 2 0 and 10 mg of catalyst.
- the autoclave was pressurised with 2.9 MPa 5% H2/CO2 and 1.1 MPa 25% O2/CO2 to give a total reaction pressure of 4 MPa.
- the autoclave was cooled to 2 °C and then stirred at 1200 rpm for 30 min.
- the hydrogenation activity of a catalyst was tested in a similar way to the direct synthesis activity. Unless otherwise stated, the autoclave was charged with 5.6 g of MeOH, 0.67 g 50 wt% H 2 0 2 and 2.23 g of HPLC grade H 2 0 and thoroughly mixed, after which 10 mg of catalyst was added.
- This solvent composition is equivalent of a 4 wt% H2O2 solution of the same volume used previously in the H2O2 synthesis experiments. 2 drops of the solvent solution each weighing around 0.04 g were removed and titrated with the acidified Ce(S0 4 )2 solution using ferroin as an indicator to determine accurately the initial H2O2 concentration.
- the autoclave was pressurised with 2.9 MPa 5% H2/CO2 and cooled to 2 °C and the reaction was carried out for 30 min at 1200 rpm stirring speed. After the reaction was complete the solvents were filtered from the catalyst and two -0.04 g aliquots of the solvent were titrated against an acidified dilute Ce(S0 4 )2 solution using ferroin as an indicator. The hydrogenation activity was calculated as ⁇ 202 IT 1 kg ca t " 1 along with the percentage of the initial H2O2 which was present at the end of the reaction.
- catalyst reusability was tested by running a synthesis reaction as outlined above but increasing the amount of catalyst to 70 mg. After the reaction was complete the solvent was filtered from the catalyst, and the catalyst was allowed to dry overnight on the filter paper. Before being retested the catalyst was dried at 1 10 °C in an oven for 1 hour to ensure the sample was completely dry. Following this procedure a synthesis reaction was run as described above.
- Temperature programmed reduction is a thermal analysis technique that allows H2 consumption to be measured while the sample undergoes a heating profile therefore indicating the temperatures at which the sample consumes H2 and has been used extensively to study catalytic systems.
- TCD Temperature programmed reduction
- the sample is heated under a flow of H2 containing gas and H2 consumption by the sample can be monitored using a TCD to analyse the gas that has passed through the sample cell.
- a plot of TCD signal against temperature can indicate at which temperature the sample undergoes reduction.
- a positive peak in the TCD signal indicates H 2 consumption.
- TPR can give an indication as to what temperature a sample needs to be reduced at to generate the desired species on a catalyst and can also give an indication of the initial species present on the catalyst.
- TPR profiles were recorded using a Thermo 1 100 series TPDRO. 0.1 g of sample was packed into the sample tube between quartz wool. Argon (15 ml min-1) was then passed through the system while it was heated from room temperature to 1 10 °C at 5 °C min "1 , where it was held for 60 min. The sample was allowed to cool to room temperature and following this the gas was switched to 10% H2 / Ar (15 ml min -1 ) and the sample was heated at 5 °C min -1 up to 800 °C. The profile was recorded using a TCD with positive polarity. - X-ray diffraction
- X-ray photoelectron spectroscopy is a characterisation technique which can give information such as composition and oxidation state of species on the surface of the catalyst to a depth of around 10 nm.
- XPS X-ray photoelectron spectroscopy
- XPS was performed using a VG EscaLab 220i spectrometer, using a standard Al-Kcr X-ray source (300 W) and an analyser pass energy of 20 eV. Samples were mounted using double-sided adhesive tape, and binding energies were referenced to the C 1 s binding energy of adventitious carbon contamination, which was taken to be 284.7 eV.
- STEM Scanning transmission electron microscopy
- XEDS Thermo-Noran X-ray energy dispersive spectroscopy
- Example 3a The 1 st and 2 nd use productivity of the 1 % Pd / 4 % Sn / Si0 2 catalyst from Example 2 was determined. The catalyst was subjected to a reductive treatment at 200 °C for 2 hours under 5 % hb/Ar and its 1 st and 2 nd use productivity was determined along with hydrogenation activity. The catalyst was subsequently subjected to a heat treatment by calcination in air at 400 °C for 3 hours. Results are summarized in Table 3.
- the 1 st and 2 nd use productivity of the 3 % Pd / 2 % Sn / Ti0 2 catalyst from Example 2 was determined.
- the catalyst was subjected to a reductive treatment at 200 °C for 2 hours under 5 % hb/Ar and its 1 st and 2 nd use productivity was determined along with hydrogenation activity.
- the catalyst was subsequently subjected to a heat treatment by calcination in air at 400 °C for 3 or 4 hours. Results are summarized in Table 4.
- the reductive treatment improves 2 nd use H2O2 productivity, but leads to an increase in H2O2 hydrogenation activity.
- the further heat treatment provides a stable catalyst and significantly suppresses (3 hour treatment) or completely inhibits (4 hour treatment) hydrogenation activity.
- TPR Temperature programmed reduction
- FIG. 2 shows the TPR profile of various bimetallic catalysts supported on ⁇ 2. All catalysts show a response at 90 °C; however the intensity of this signal is decreased considerably relative to the monometallic Pd catalyst. Without wishing to be bound by theory, this observation may either suggest that the presence of Sn inhibits the formation of palladium-p-hydride or that Pd is present in a different form, such as a Pd-Sn-O x mixed oxide and/or alloy. Further, the TPR profiles of the bimetallic catalysts show a new unique feature at ca. 150 °C. This feature is not present in the TPR profiles of the monometallic catalysts and coincides with the decrease in the intensity of the palladium-p-hydride signal.
- FIG. 3 shows X-ray diffraction patterns of selected Sn-Pd bimetallic catalysts supported on S1O2 and T1O2.
- Figure 3 shows XRD of the monometallic 5% Pd, 5% Sn and bimetallic 2.5% Pd 2.5% Sn supported on silica after calcination at 500 °C for 3 hours.
- the 5% Pd and 5% Sn materials both show a broad reflection at 22° from the poorly crystalline silica support.
- the monometallic Pd and Sn catalysts both show reflections characteristic of the PdO and SnO2 phases respectively.
- the bimetallic catalyst shows weak features of both PdO and SnO2.
- Figure 4 illustrates how the XRD pattern varies when the Sn:Pd ratio is varied.
- PdO features are indicated by the dashed line and as the Pd content is decreased from 5% the features become less intense.
- the same can be seen with the SnO2 reflections indicated by the dotted lines.
- the reflection at 34° is a combination of both SnO2 and PdO reflections.
- XPS spectra were recorded for the various catalysts supported on S1O2 after various heat treatments and also for monometallic catalysts.
- Figure 6 shows the Pd(3d) XPS spectra of monometallic and bimetallic catalysts after calcination at 500 °C for 3 hours.
- the monometallic Pd sample shows peaks indicating the Pd is present in the 2+ oxidation state which agrees with the observation of PdO in the XRD analysis.
- the Pd(3d) XPS spectra of the bimetallic catalysts shows a shift to higher binding energy relative to the monometallic catalysts which indicates that the Pd is in a more oxidised state, possibly indicating electron transfer from Pd to Sn.
- Figure 7 shows the Pd(3d) XPS spectra for the of 1 % Pd / 4% Sn / Si0 2 catalyst after calcination at 500 °C for 3 hours and subsequent reduction at various temperatures for 2 h under 5% H2 / Ar.
- a clear shift from Pd(ll) to metallic Pd can be seen after reduction at 100 °C and remains unchanged during reduction upto 200 °C.
- Figure 8 shows the Pd(3d) spectra of the reduced 1 % Pd / 4% Sn / S1O2 after subsequent heat treatment at 400 °C in air for 2 hours and 3 hours.
- the spectra show that on heating under air at high temperatures for various times the Pd returns to the Pd(ll) oxidation state and the Pd(0) species begins to disappear; after 3 h the catalyst predominantly contains Pd(ll).
- the observation that after a reduction and oxidation following an initial oxidation switches off the hydrogenation activity indicates a change in nanoparticle morphology or composition as the catalyst is substantially returned to its starting state in terms of oxidation state.
- Figure 9 shows the Sn(3d 5 / 2 ) and Pd(3d) XPS spectra for a 3 % Pd / 2 % Sn / TiO 2 catalyst following oxidation at 500 °C for 3 hours in air (O), subsequent reduction at 200°C for 2 hours under 5% H2 / Ar (OR), a further oxidation treatment at 400 °C for 3 hours in air oxidation (ORO) and further sequential reduction (at 200°C for 2 hours under 5% H2 / Ar) and then oxidation (at 400 °C for 3 hours in air oxidation) i.e., an ORORO process.
- Microscopy and XPS reveals that there are three kinds of structures present in the catalyst after the O-R-O treatment cycle: catalytic nanoparticles (-2-10 nm) that contain both Sn and Pd in varying ratios, smaller Pd rich species and a SnO 2 amorphous layer which covers the TiO 2 support in places. It is observed that the SnO 2 amorphous layer becomes thicker (initially - 1 nm after first oxidation step then increasing to 2-3 nm after ORO). The amorphous layer appears to encapsulate the smaller Pd-rich species.
- Figure 10 shows the smaller Pd-rich particles (box 2) encapsulated by the amorphous Sn0 2 layer (box 1 ).
- Pd-Sn-O x nanoparticles are the main actives for hydrogen peroxide production, with Sn acting as a spacer splitting up the Pd surfaces. These species are believed to be mixed oxide particles as no significant contribution from metallic species is seen in the XPS.
- the smaller, Pd- rich, species are active species for hydrogenation and decomposition. However, after the ORO treatment cycle and due to strong metal-support interaction, these smaller species are encapsulated by the Sn0 2 amorphous layer, preventing them from hydrogenating hydrogen peroxide.
- Figure 1 1 is a STEM image showing a Pd-Sn- Ox nanoparticle (2) partially embedded in the amorphous Sn0 2 layer (4) which "sits on" the highly ordered Ti0 2 support (6).
- the obtained powder was subjected to various heat treatments: (i) calcination at 500 °C in air for 3 hours followed by reductive treatment at 200°C for 2 hours in 5 % H 2 /Argon; and (ii) calcination at 500 °C in air for 3 hours, followed by reductive treatment at 200°C for 2 hours in 5 % H 2 /Argon, followed by heat treatment at 400°C for 4 hours in air.
- the heat treated catalysts were tested in a direct synthesis reaction in accordance with the method described above.
- Example 8 Pd-Ni catalyst preparation, analysis and testing
- Pd-Ni/TiC>2 catalysts were prepared with varied Pd:Ni ratios and a total metal loading of 5 wt%.
- the metal precursors used were Pd(NOs)2 and NiC . 6H2O, all catalysts were oxidised at 500°C for 3 hours.
- Degradation was tested under the following conditions: 0.01 g catalyst, 5% H2/CO2 (2.9 MPa), 1200 rpm, 0.68 g 50 wt% H2O2, 7.82 g water solvent, 20°C, 30 mins.
- MP-AES analysis of the post-reaction solution has shown that there is no Ni or Pd present after a 30 minute reaction using the O-R-0 treated catalyst. Further, activity is maintained upon re-use of the catalyst. Thus, the O-R-0 treated catalyst is stable.
- the catalyst was also tested under 'standard' hydrogen peroxide synthesis conditions, as summarised in Table 1 1.
- the catalyst is not only productive with only 0.5% Pd, but importantly, testing indicates that it has a very low to no activity for the hydrogenation/decomposition of hydrogen peroxide, enabling the production of high concentrations of hydrogen peroxide with repeated reactions.
- All catalysts were prepared by conventional impregnation. A palladium nitrate solution in water (12.5 mg/ml, confirmed by MP-AES) and a zinc chloride solution in water (12.5 mg/ml, confirmed by MP-AES) were combined with titania support in the required ratio and heated with stirring until a thick paste was achieved. This thick paste was dried (1 10°C, 16h) followed by heat treatment as described for each sample.
- Pd-Zn/Ti0 2 catalysts were prepared with varied Pd:Zn ratios (as summarised in Table 13) and a total metal loading of 5 wt%.
- the metal precursors used were Pd(NOs) 2 and ZnCI 2 .
- Catalysts were either oxidised at 500°C for 3 hours (i.e., ⁇ '), or oxidised at 500°C and reduced in H 2 /Ar at 200°C for 2 hr (i.e., 'OR'), or oxidised at 500°C for 3 hours, reduced in H 2 /Ar at 200°C for 2 hr followed again by oxidizing in air at 500°C for 3 hr (i.e., ORO').
- Table 13 13
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Inorganic Chemistry (AREA)
- Catalysts (AREA)
Abstract
Description
Claims
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB201502411A GB201502411D0 (en) | 2015-02-13 | 2015-02-13 | Catalyst for direct synthesis of hydrogen peroxide |
PCT/GB2016/050308 WO2016128738A1 (en) | 2015-02-13 | 2016-02-10 | Catalyst for direct synthesis of hydrogen peroxide |
Publications (1)
Publication Number | Publication Date |
---|---|
EP3256248A1 true EP3256248A1 (en) | 2017-12-20 |
Family
ID=52781549
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP16704892.5A Withdrawn EP3256248A1 (en) | 2015-02-13 | 2016-02-10 | Catalyst for direct synthesis of hydrogen peroxide |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP3256248A1 (en) |
CN (1) | CN107530684B (en) |
GB (1) | GB201502411D0 (en) |
WO (1) | WO2016128738A1 (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN110395696A (en) * | 2019-07-26 | 2019-11-01 | 四川轻化工大学 | A method of hydrogen peroxide is synthesized based on Pd radicel duplex metal catalysis formic acid |
CN115318286B (en) * | 2022-08-24 | 2024-03-15 | 华东理工大学 | Platinum catalyst for catalytic combustion of propane and preparation method and application thereof |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3399132A (en) * | 1966-07-28 | 1968-08-27 | Chevron Res | Hydrocaracking of hydrocarbons with a catalyst composite comprising nickel and tin associated with a porous acidic inorganic oxide carrier |
JPH06305715A (en) * | 1993-04-19 | 1994-11-01 | Mitsubishi Gas Chem Co Inc | Production of hydrogen peroxide |
US6500968B2 (en) * | 1998-08-26 | 2002-12-31 | Hydrocarbon Technologies, Inc. | Process for selective oxidation of organic feedstocks with hydrogen peroxide |
DE19915681A1 (en) * | 1999-04-07 | 2000-10-12 | Basf Ag | Process for the production of platinum metal catalysts |
US7045479B2 (en) * | 2003-07-14 | 2006-05-16 | Headwaters Nanokinetix, Inc. | Intermediate precursor compositions used to make supported catalysts having a controlled coordination structure and methods for preparing such compositions |
CN102781571B (en) * | 2009-12-03 | 2015-06-17 | 巴斯夫欧洲公司 | Catalyst and method for producing an amine |
KR20140063799A (en) * | 2011-09-16 | 2014-05-27 | 솔베이(소시에떼아노님) | Catalyst for h202 synthesis and method for preparing such catalyst |
EP2589431A1 (en) * | 2011-11-07 | 2013-05-08 | Solvay Sa | A catalyst for direct synthesis of hydrogen peroxide |
CN104902994B (en) * | 2012-11-06 | 2018-01-02 | 索尔维公司 | the direct synthesis of hydrogen peroxide |
GB201314600D0 (en) * | 2013-08-15 | 2013-10-02 | Univ Cardiff | Catalyst for direct synthesis of hyrdogen peroxide |
-
2015
- 2015-02-13 GB GB201502411A patent/GB201502411D0/en not_active Ceased
-
2016
- 2016-02-10 EP EP16704892.5A patent/EP3256248A1/en not_active Withdrawn
- 2016-02-10 WO PCT/GB2016/050308 patent/WO2016128738A1/en active Application Filing
- 2016-02-10 CN CN201680010051.XA patent/CN107530684B/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
WO2016128738A1 (en) | 2016-08-18 |
GB201502411D0 (en) | 2015-04-01 |
CN107530684B (en) | 2021-10-26 |
CN107530684A (en) | 2018-01-02 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Navalón et al. | Photocatalytic CO2 reduction using non‐titanium metal oxides and sulfides | |
Dhakshinamoorthy et al. | Photocatalytic CO 2 reduction by TiO 2 and related titanium containing solids | |
US10202320B2 (en) | Catalyst and method for its preparation | |
Chen et al. | Recent advances in TiO2‐based catalysts for N2 reduction reaction | |
Ma et al. | Tuning electronic structure of PdZn nanocatalyst via acid-etching strategy for highly selective and stable electrolytic nitrogen fixation under ambient conditions | |
EP2098290B1 (en) | Method for producing ruthenium oxide loaded body and method for producing chlorine | |
JP5588107B2 (en) | Improvement of catalyst | |
Liu et al. | Promotional effect of Mn-doping on the catalytic performance of NiO sheets for the selective oxidation of styrene | |
EP3033170B1 (en) | Catalyst for direct synthesis of hydrogen peroxide | |
Kute et al. | A review on the synthesis and applications of sustainable copper-based nanomaterials | |
Murcia et al. | Photocatalytic ethanol oxidative dehydrogenation over Pt/TiO2: effect of the addition of blue phosphors | |
Chen et al. | Enhanced photoproduction of hydrogen on Pd/TiO2 prepared by mechanochemistry | |
Slot et al. | Surface oxidation of Ti3C2Tx enhances the catalytic activity of supported platinum nanoparticles in ammonia borane hydrolysis | |
KR20190079113A (en) | Catalyst and electrode and electro-fenton reaction system usingby | |
WO2010055341A2 (en) | Improvements in catalytic processes | |
Sabaté et al. | Synthesis of isomorphically substituted Ru manganese molecular sieves and their catalytic properties for selective alcohol oxidation | |
Chukeaw et al. | Multimetallic catalysts of RuO 2–CuO–Cs 2 O–TiO 2/SiO 2 for direct gas-phase epoxidation of propylene to propylene oxide | |
EP3256248A1 (en) | Catalyst for direct synthesis of hydrogen peroxide | |
Wang et al. | Ultrathin black TiO 2 nanosheet-assembled microspheres with high stability for efficient solar-driven photocatalytic hydrogen evolution | |
JP2009249206A (en) | Titanium oxide particle surface-modified by carbon nanotube whose tip is carried with metallic element | |
CN108014792A (en) | A kind of Ethylene Fraction Selective Hydrogenation, preparation method and application | |
Ahmed et al. | In-situ synthesis and characterizations of Bi2 (O, S) 3/Zn (O, S) composites for visible light hexavalent chromium reduction | |
JP4597024B2 (en) | Cycloolefin production catalyst and cycloolefin production method | |
KR20120139675A (en) | Method for producing propylene oxide | |
Altaee et al. | Pd-Au nanoparticles supported reduced graphene oxide nanoplatelets toward aerobic selective oxidation of benzoyl alcohol |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE |
|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE |
|
17P | Request for examination filed |
Effective date: 20170726 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
AX | Request for extension of the european patent |
Extension state: BA ME |
|
DAV | Request for validation of the european patent (deleted) | ||
DAX | Request for extension of the european patent (deleted) | ||
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: EXAMINATION IS IN PROGRESS |
|
17Q | First examination report despatched |
Effective date: 20190917 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: EXAMINATION IS IN PROGRESS |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
|
18D | Application deemed to be withdrawn |
Effective date: 20220831 |