CH678857A5 - Prodn. of low molecular wt. cpds. for pharmaceuticals - comprises degradation of sulphur free lignin by photocatalytic oxidn. - Google Patents
Prodn. of low molecular wt. cpds. for pharmaceuticals - comprises degradation of sulphur free lignin by photocatalytic oxidn. Download PDFInfo
- Publication number
- CH678857A5 CH678857A5 CH90089A CH90089A CH678857A5 CH 678857 A5 CH678857 A5 CH 678857A5 CH 90089 A CH90089 A CH 90089A CH 90089 A CH90089 A CH 90089A CH 678857 A5 CH678857 A5 CH 678857A5
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- CH
- Switzerland
- Prior art keywords
- varied
- lignin
- solution
- sep
- catalyst
- Prior art date
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- 229920005610 lignin Polymers 0.000 title claims abstract description 33
- 239000003814 drug Substances 0.000 title abstract 2
- 230000015556 catabolic process Effects 0.000 title description 3
- 238000006731 degradation reaction Methods 0.000 title description 3
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 title description 2
- 230000001699 photocatalysis Effects 0.000 title description 2
- 239000005864 Sulphur Substances 0.000 title 1
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical group O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims abstract description 16
- 239000003054 catalyst Substances 0.000 claims abstract description 16
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N phenol group Chemical group C1(=CC=CC=C1)O ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 claims abstract description 5
- 239000003960 organic solvent Substances 0.000 claims abstract description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims abstract 9
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract 6
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract 5
- 229910052760 oxygen Inorganic materials 0.000 claims abstract 5
- 239000001301 oxygen Substances 0.000 claims abstract 5
- RYHBNJHYFVUHQT-UHFFFAOYSA-N 1,4-Dioxane Chemical compound C1COCCO1 RYHBNJHYFVUHQT-UHFFFAOYSA-N 0.000 claims abstract 3
- 239000007800 oxidant agent Substances 0.000 claims abstract 3
- 239000002904 solvent Substances 0.000 claims abstract 3
- 238000000034 method Methods 0.000 claims description 38
- 150000001875 compounds Chemical class 0.000 claims description 8
- 239000004408 titanium dioxide Substances 0.000 claims description 7
- 125000003678 cyclohexadienyl group Chemical group C1(=CC=CCC1)* 0.000 claims description 6
- 150000001735 carboxylic acids Chemical class 0.000 claims description 4
- 230000003647 oxidation Effects 0.000 claims description 4
- 238000007254 oxidation reaction Methods 0.000 claims description 4
- 230000005526 G1 to G0 transition Effects 0.000 claims description 3
- 238000006555 catalytic reaction Methods 0.000 claims description 3
- QGLKJKCYBOYXKC-UHFFFAOYSA-N nonaoxidotritungsten Chemical compound O=[W]1(=O)O[W](=O)(=O)O[W](=O)(=O)O1 QGLKJKCYBOYXKC-UHFFFAOYSA-N 0.000 claims description 3
- 238000013033 photocatalytic degradation reaction Methods 0.000 claims description 3
- 150000003384 small molecules Chemical class 0.000 claims description 3
- 229910001930 tungsten oxide Inorganic materials 0.000 claims description 3
- LCPVQAHEFVXVKT-UHFFFAOYSA-N 2-(2,4-difluorophenoxy)pyridin-3-amine Chemical compound NC1=CC=CN=C1OC1=CC=C(F)C=C1F LCPVQAHEFVXVKT-UHFFFAOYSA-N 0.000 claims 4
- CHQMHPLRPQMAMX-UHFFFAOYSA-L sodium persulfate Substances [Na+].[Na+].[O-]S(=O)(=O)OOS([O-])(=O)=O CHQMHPLRPQMAMX-UHFFFAOYSA-L 0.000 claims 4
- 239000007787 solid Substances 0.000 claims 2
- LHGVFZTZFXWLCP-UHFFFAOYSA-N guaiacol Chemical compound COC1=CC=CC=C1O LHGVFZTZFXWLCP-UHFFFAOYSA-N 0.000 abstract description 14
- 239000002253 acid Substances 0.000 abstract description 8
- 229960001867 guaiacol Drugs 0.000 abstract description 7
- 150000001991 dicarboxylic acids Chemical class 0.000 abstract description 6
- RRAFCDWBNXTKKO-UHFFFAOYSA-N eugenol Chemical compound COC1=CC(CC=C)=CC=C1O RRAFCDWBNXTKKO-UHFFFAOYSA-N 0.000 abstract description 6
- TZUORCZPIKYDQG-UHFFFAOYSA-N 2-methoxy-5-propylphenol Chemical compound CCCC1=CC=C(OC)C(O)=C1 TZUORCZPIKYDQG-UHFFFAOYSA-N 0.000 abstract description 3
- NPBVQXIMTZKSBA-UHFFFAOYSA-N Chavibetol Natural products COC1=CC=C(CC=C)C=C1O NPBVQXIMTZKSBA-UHFFFAOYSA-N 0.000 abstract description 3
- 239000005770 Eugenol Substances 0.000 abstract description 3
- UVMRYBDEERADNV-UHFFFAOYSA-N Pseudoeugenol Natural products COC1=CC(C(C)=C)=CC=C1O UVMRYBDEERADNV-UHFFFAOYSA-N 0.000 abstract description 3
- 229960002217 eugenol Drugs 0.000 abstract description 3
- PXIKRTCSSLJURC-UHFFFAOYSA-N p-propylguaiacol Natural products CCCC1=CC=C(O)C(OC)=C1 PXIKRTCSSLJURC-UHFFFAOYSA-N 0.000 abstract description 3
- ZENOXNGFMSCLLL-UHFFFAOYSA-N vanillyl alcohol Chemical compound COC1=CC(CO)=CC=C1O ZENOXNGFMSCLLL-UHFFFAOYSA-N 0.000 abstract description 3
- 238000003786 synthesis reaction Methods 0.000 abstract description 2
- MGNZXYYWBUKAII-UHFFFAOYSA-N cyclohexa-1,3-diene Chemical compound C1CC=CC=C1 MGNZXYYWBUKAII-UHFFFAOYSA-N 0.000 abstract 2
- JRKICGRDRMAZLK-UHFFFAOYSA-L persulfate group Chemical group S(=O)(=O)([O-])OOS(=O)(=O)[O-] JRKICGRDRMAZLK-UHFFFAOYSA-L 0.000 abstract 2
- PFTAWBLQPZVEMU-DZGCQCFKSA-N (+)-catechin Chemical compound C1([C@H]2OC3=CC(O)=CC(O)=C3C[C@@H]2O)=CC=C(O)C(O)=C1 PFTAWBLQPZVEMU-DZGCQCFKSA-N 0.000 abstract 1
- 230000015572 biosynthetic process Effects 0.000 abstract 1
- 229950001002 cianidanol Drugs 0.000 abstract 1
- 239000003622 immobilized catalyst Substances 0.000 abstract 1
- 230000001678 irradiating effect Effects 0.000 abstract 1
- 230000001706 oxygenating effect Effects 0.000 abstract 1
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 18
- 239000000243 solution Substances 0.000 description 11
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 7
- NGSWKAQJJWESNS-UHFFFAOYSA-N 4-coumaric acid Chemical compound OC(=O)C=CC1=CC=C(O)C=C1 NGSWKAQJJWESNS-UHFFFAOYSA-N 0.000 description 6
- RGHHSNMVTDWUBI-UHFFFAOYSA-N 4-hydroxybenzaldehyde Chemical compound OC1=CC=C(C=O)C=C1 RGHHSNMVTDWUBI-UHFFFAOYSA-N 0.000 description 6
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 6
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 description 6
- JMSVCTWVEWCHDZ-UHFFFAOYSA-N syringic acid Chemical compound COC1=CC(C(O)=O)=CC(OC)=C1O JMSVCTWVEWCHDZ-UHFFFAOYSA-N 0.000 description 6
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 4
- 239000012670 alkaline solution Substances 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- NGSWKAQJJWESNS-ZZXKWVIFSA-M 4-Hydroxycinnamate Natural products OC1=CC=C(\C=C\C([O-])=O)C=C1 NGSWKAQJJWESNS-ZZXKWVIFSA-M 0.000 description 3
- DFYRUELUNQRZTB-UHFFFAOYSA-N Acetovanillone Natural products COC1=CC(C(C)=O)=CC=C1O DFYRUELUNQRZTB-UHFFFAOYSA-N 0.000 description 3
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 description 3
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 3
- 235000011037 adipic acid Nutrition 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 3
- 239000001569 carbon dioxide Substances 0.000 description 3
- 229910002092 carbon dioxide Inorganic materials 0.000 description 3
- 238000004587 chromatography analysis Methods 0.000 description 3
- 238000004128 high performance liquid chromatography Methods 0.000 description 3
- YQUVCSBJEUQKSH-UHFFFAOYSA-N protochatechuic acid Natural products OC(=O)C1=CC=C(O)C(O)=C1 YQUVCSBJEUQKSH-UHFFFAOYSA-N 0.000 description 3
- 239000011541 reaction mixture Substances 0.000 description 3
- 235000011044 succinic acid Nutrition 0.000 description 3
- YIBXWXOYFGZLRU-UHFFFAOYSA-N syringic aldehyde Natural products CC12CCC(C3(CCC(=O)C(C)(C)C3CC=3)C)C=3C1(C)CCC2C1COC(C)(C)C(O)C(O)C1 YIBXWXOYFGZLRU-UHFFFAOYSA-N 0.000 description 3
- WKOLLVMJNQIZCI-UHFFFAOYSA-N vanillic acid Chemical compound COC1=CC(C(O)=O)=CC=C1O WKOLLVMJNQIZCI-UHFFFAOYSA-N 0.000 description 3
- TUUBOHWZSQXCSW-UHFFFAOYSA-N vanillic acid Natural products COC1=CC(O)=CC(C(O)=O)=C1 TUUBOHWZSQXCSW-UHFFFAOYSA-N 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- OFOBLEOULBTSOW-UHFFFAOYSA-N Malonic acid Chemical compound OC(=O)CC(O)=O OFOBLEOULBTSOW-UHFFFAOYSA-N 0.000 description 2
- 239000007868 Raney catalyst Substances 0.000 description 2
- NPXOKRUENSOPAO-UHFFFAOYSA-N Raney nickel Chemical compound [Al].[Ni] NPXOKRUENSOPAO-UHFFFAOYSA-N 0.000 description 2
- 229910000564 Raney nickel Inorganic materials 0.000 description 2
- WNLRTRBMVRJNCN-UHFFFAOYSA-N adipic acid Chemical compound OC(=O)CCCCC(O)=O WNLRTRBMVRJNCN-UHFFFAOYSA-N 0.000 description 2
- 150000001279 adipic acids Chemical class 0.000 description 2
- 150000001491 aromatic compounds Chemical class 0.000 description 2
- KRVSOGSZCMJSLX-UHFFFAOYSA-L chromic acid Substances O[Cr](O)(=O)=O KRVSOGSZCMJSLX-UHFFFAOYSA-L 0.000 description 2
- -1 cyclohexadienyl compound Chemical class 0.000 description 2
- 239000007857 degradation product Substances 0.000 description 2
- 239000003480 eluent Substances 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- AWJWCTOOIBYHON-UHFFFAOYSA-N furo[3,4-b]pyrazine-5,7-dione Chemical compound C1=CN=C2C(=O)OC(=O)C2=N1 AWJWCTOOIBYHON-UHFFFAOYSA-N 0.000 description 2
- 229910052736 halogen Inorganic materials 0.000 description 2
- 150000002367 halogens Chemical class 0.000 description 2
- 238000005984 hydrogenation reaction Methods 0.000 description 2
- 150000002691 malonic acids Chemical class 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 150000002913 oxalic acids Chemical class 0.000 description 2
- 238000005949 ozonolysis reaction Methods 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- KDYFGRWQOYBRFD-UHFFFAOYSA-N succinic acid Chemical compound OC(=O)CCC(O)=O KDYFGRWQOYBRFD-UHFFFAOYSA-N 0.000 description 2
- 150000003444 succinic acids Chemical class 0.000 description 2
- HIXDQWDOVZUNNA-UHFFFAOYSA-N 2-(3,4-dimethoxyphenyl)-5-hydroxy-7-methoxychromen-4-one Chemical compound C=1C(OC)=CC(O)=C(C(C=2)=O)C=1OC=2C1=CC=C(OC)C(OC)=C1 HIXDQWDOVZUNNA-UHFFFAOYSA-N 0.000 description 1
- 239000012028 Fenton's reagent Substances 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- 229920001131 Pulp (paper) Polymers 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 239000001361 adipic acid Substances 0.000 description 1
- 239000003463 adsorbent Substances 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- RTZKZFJDLAIYFH-UHFFFAOYSA-N ether Substances CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- XMBWDFGMSWQBCA-UHFFFAOYSA-N hydrogen iodide Chemical compound I XMBWDFGMSWQBCA-UHFFFAOYSA-N 0.000 description 1
- 229940071870 hydroiodic acid Drugs 0.000 description 1
- 230000031700 light absorption Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 230000020477 pH reduction Effects 0.000 description 1
- 125000005385 peroxodisulfate group Chemical group 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 239000000825 pharmaceutical preparation Substances 0.000 description 1
- 229940127557 pharmaceutical product Drugs 0.000 description 1
- 238000007146 photocatalysis Methods 0.000 description 1
- 238000001782 photodegradation Methods 0.000 description 1
- 239000002574 poison Substances 0.000 description 1
- 231100000614 poison Toxicity 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 238000004366 reverse phase liquid chromatography Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 239000010802 sludge Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 125000004079 stearyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 239000001384 succinic acid Substances 0.000 description 1
- LSNNMFCWUKXFEE-UHFFFAOYSA-L sulfite Chemical compound [O-]S([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-L 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 229910021653 sulphate ion Inorganic materials 0.000 description 1
- 238000000870 ultraviolet spectroscopy Methods 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 239000011701 zinc Substances 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
- B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
- B01J19/08—Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor
- B01J19/12—Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor employing electromagnetic waves
- B01J19/122—Incoherent waves
- B01J19/123—Ultraviolet light
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C27/00—Processes involving the simultaneous production of more than one class of oxygen-containing compounds
- C07C27/10—Processes involving the simultaneous production of more than one class of oxygen-containing compounds by oxidation of hydrocarbons
- C07C27/16—Processes involving the simultaneous production of more than one class of oxygen-containing compounds by oxidation of hydrocarbons with other oxidising agents
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C41/00—Preparation of ethers; Preparation of compounds having groups, groups or groups
- C07C41/01—Preparation of ethers
- C07C41/18—Preparation of ethers by reactions not forming ether-oxygen bonds
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/78—Separation; Purification; Stabilisation; Use of additives
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Toxicology (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
Prodn. of low-molecular-wt. cpds. (I) from S-free lignin comprises dissolving the lignin in an organic solvent, oxygenating the soln. (sic;) and irradiating the soln. with UV light with a wavelength of at least 140 nm for at leat 20 min at 20-90 deg C in the presence of an immobilised catalyst. The oxygen is esp. supplied by an oxidising agent such as Na persulphate. The Na persulphate concn. is 0.05-0.2 M. The catalyst is TiO2 or WO3, e.g. deposited on a tubular filter in a photoreactor. The solvent is phenol, dioxan, MeOH or EtOH. The lignin concn. is 70-100% (esp. 92%) of satn.. USE - (I) are stated to include cpds. useful for the synthesis of pharmaceuticals, e.g. guaiacol, catechuic acid, isohemipinic acid, 4-n-propylguaiacol, vanillol and eugenol. (I) may be reduced to the corresp. cyclohexadiene derivs., which may be oxidised to dicarboxylic acids.
Description
L'invention traite de la dégradation photocatalytique de la lignine exempte de soufre, obtenue par le procédé Organosolv, en des substance chimiques telles que le guaiacol, acide pyrocatéchique, acide isohémipinique, 4-n propylguaiacol, vanillol et eugénol.
La seconde partie de l'invention traite de la réduction du noyau aromatique de ces produits de dégradation de la lignine en des composés contenant une entité cyclohexadiényl. Par un processus d'oxydation on transforme finalement cette entité cyclohexadiényl en des acides dicarboxyliques, qui sont des composés avec une variété d'applications.
L'objectif principal de cette invention est de convertir la lignine exempte de soufre en des produits chimiques importants pour la synthèse organique des produits pharmaceutiques. Ayant une utilité commerciale très restreinte, la lignine provoque de sérieux problèmes écologiques et économiques au niveau de l'élimination. Dans le passé, une quantité importante de lignine était déversée dans les rivières, perturbant ainsi la balance écologique de l'environnement. Seulement une partie négligeable de la lignine a été utilisée pour le forage des boues, ou calcinée pour produire des adsorbants tels que le charbon actif, ou brulée pour produire de l'énergie. Malheureusement, la majeure partie de la lignine issue de la fabrication de pâte à papier (environ 200 millions de tonnes/an) est inutilisée.
Grâce au procédé Organosolv on obtient la lignine exempte de soufre qui est plus facile à traiter.
Les méthodes actuelles de fabrication de pâte à papier produisent de la lignine qui se prête mal aux réactions catalytiques: la présence des composés tels que le sulfite et le sulfate empoisonnent les catalyseurs. La lignine obtenue par le procédé Organosolv est exempte de soufre et peut être dégradée plus efficacement par l'utilisation de catalyseurs.
Par le procédé Organosolv on obtient une solution alcaline de la lignine; par un procédé électrolytique ou par acidification on enlève le sodium de cette solution alcaline, la lignine se précipite, par centrifugation on obtient la lignine sous forme d'une poudre brune.
Le procédé inventif pour l'obtention de composés de poids molécualires bas à partir de la lignine exempte de soufre est caractérisé dans les revendications précédentes.
On peut soit utiliser directement ladite solution alcaline de la lignine, ou dissoudre la poudre brune dans un solvant organique tel que le phénol. On fait ensuite circuler cette solution mélangée avec de l'eau oxygénée (B) dans un photoréacteur en présence d'un catalyseur tel que le dioxyde de titane. On introduit la solution à travers A dans le photoréacteur. L'avantage de cette méthode est que l'on utilise un catalyseur en phase stationnaire, c'est-à-dire on dépose le dioxyde de titane (T102) sur un filtre tubulaire (D). Ainsi on évite une étape de filtration du catalyseur à la sortie. Dans cette configuration, les sources d'irradiation sont composées d'une lampe halogène (C) (1000 W) logée à l'intérieur du tube, et de deux autres lampes halogènes (C) (2 x 1000 W) à l'extérieur; l'irradiation se fait donc sur la surface interne et externe du filtre tubulaire.
A l'aide d'une pompe (E) on fait circuler la solution a travers le photoréacteur. Le débit de la pompe est un compromis entre un temps de séjour de la solution sur le catalyseur nécessaire pour l'efficacité de la photocatalyse, et un écoulement suffisant pour refroidir les lampes. La température du mélange réactionnel varie entre 20 et 40 DEG C. Un débit d'environ 1000 ml/min est utilisé.
L'absorption de la lumière avec une énergie supérieure à celle de la bande interdite du sémi-conducteur fait migrer un électron de la bande de valence vers la bande de conduction, créant ainsi un manque d'électron dans la bande de valence. Les paires électrontrous peuvent recombiner, ou les électrons peuvent être captés par les espèces réductrices, ou les trous par les espèces oxydantes. Dans ce système, la séquence proposée pour le début de la photodégradation est la suivante:
EMI3.1
On peut faire une analogie avec le réactif de Fenton qui produit des radicaux OH<+>:
H2O2 + Fe<2><+> -> OH<-> + OH<+> + Fe3<+>
D NOTELEMENT &sqsup& &sqsub& NOTEQUAL APPROX &anq& SIMILAR NOTEQUAL PLANCK (-) NOTAPPROX &odot& APPROX &sqsub& =(-) &odot& &mstpos& NOTELEMENT &sqsup& 9 l 1/4 0 BEcause NOTELEMENT &sqsub& HOMOTHETIC NOTELEMENT &sinew& &sinew& NOTELEMENT &prurel& &sinew& &mstpos& NOTEQUAL &sqsup& SIMILAR &anq& &sqsup& &sqsup& &anq& = &prurel& APPROX NOTELEMENT &mstpos& NOTEQUAL &mstpos& &anq& NOTSIMILAR &prurel& &anq& &prurel& NOTELEMENT NOTELEMENT &prurel& APPROX NOTELEMENT &sqsup& SIMILAR = HOMOTHETIC BEcause = &sqsup& ¨& &sqsup& &sqsup& &anq& HOMOTHETIC BEcause &mstpos& NOTELEMENT &sqsup& &sinew& NOTELEMENT &mstpos& &sqsup& NOTPARALLEL PLANCK NOTELEMENT &mstpos& NOTELEMENT guaiacol, acide protocatéchique, acide isohémipinique, 4-n propylguaiacol, vanillol et eugénol.
La deuxième partie de cette invention traite du processus de réduction des produits de la dégradation de la lignine en des composés cyclohexadiényls et de l'oxydation en dés acides dicarboxyliques tels que les acides oxalique, malonique, succinique et adipique.
On peut utiliser le nickel de Raney comme catalyseur pour l'hydrogénation de ces composés aromatiques, ou les traiter par une solution d'un métal dans l'ammoniaque liquide.
Finalement on oxyde le composé cyclohexadiényl à l'aide de l'acide chromique, ou on fait un ozonolyse pour obtenir les acides dicarboxyliques. On utilise la chromatographie HPLC pour identifier ces acides carboxyliques, la présence d'acide acétique a pu être constatée.
Exemple 1
Dans un réservoir on met 1500 g de la solution alcaline de lignine dans 150 ml de phénol, puis on ajoute 25 ml d'eau oxygénée. On fait circuler la solution à travers un photoréacteur qui contient un filtre tubulaire sur lequel on a déposé une couche de dioxyde de titane (10 mg/cm<3>). Ensuite, on irradie le mélange réactionnel à l'aide d'une lampe qui emet dans l'ultra-violet ( lambda max = 260 nm). On laisse réagir pendant 1 heure, puis on fait des prises aliquotes pour les analyses suivantes:
1) spectrophotométrie UV dans un domaine 250 nm - 350 nm, on utilise une cellule en quartz de 1 mm et de 1 cm;
2) chromatographie liquide, à phase inverse avec un appareil HPLC. On utilise une colonne Micropak CH-10 (octadécyl).
Comme éluant on utilise un mélange eau/acétronitrile dans les proportions 65%:35%.
<tb><TABLE> Columns=2
<tb>Title: Résultats des analyses:
(% en poids par 100 g de lignine)
<tb> <SEP>guaiacol <SEP>16%
<tb> <SEP>p-hydroxybenzaldéhyde <SEP>10%
<tb> <SEP>acide vanillique <SEP>17%
<tb> <SEP>acide syringique <SEP>8%
<tb> <SEP>acide ferrulique <SEP>10%
<tb> <SEP>acide p-coumarique <SEP>8%
<tb> <SEP>acide acétique <SEP>10%
<tb> <SEP>gaz carbonique <SEP>13%
<tb> <SEP>eau <SEP>5%
<tb></TABLE>
Exemple 2
On répète l'experience 1, mais on remplace le dioxyde de titane par l'oxyde de tungstène. D'apres les analyses on constate une petite variation dans la proportion des composés obtenus.
<tb><TABLE> Columns=2
<tb>Title: Résultats des analyses:
(% en poids par 100 g de lignine)
<tb> <SEP>guaiacol <SEP>18%
<tb> <SEP>p-hydroxybenzaldéhyde <SEP>8%
<tb> <SEP>acide vanillique <SEP>10%
<tb> <SEP>acide syringique <SEP>11%
<tb> <SEP>acide ferrulique <SEP>7%
<tb> <SEP>acide p-coumarique <SEP>11%
<tb> <SEP>acide acétique <SEP>14%
<tb> <SEP>gaz carbonique <SEP>13%
<tb> <SEP>eau <SEP>4%
<tb></TABLE>
Exemple 3
On répète de nouveau l'expérience 1, on utilise le dioxyde de titane comme catalyseur, mais on remplace l'eau oxygénée par une solution aqueuse de peroxodisulfate. On remarque aussi une varia tion dans la proportion des produits de dégradation obtenus.
<tb><TABLE> Columns=2
<tb>Title: Résultats des analyses:
(% en poids par 100 g de lignine)
<tb> <SEP>guaiacol <SEP>25%
<tb> <SEP>p-hydroxybenzaldéhyde <SEP>8%
<tb> <SEP>acide vanillique <SEP>10%
<tb> <SEP>acide syringique <SEP>9%
<tb> <SEP>acide ferrulique <SEP>8%
<tb> <SEP>acide p-coumarique <SEP>5%
<tb> <SEP>acide acétique <SEP>12%
<tb> <SEP>gaz carbonique <SEP>14%
<tb> <SEP>eau <SEP>6%
<tb></TABLE>
Exemple 4
On mélange 1000 g de guaiacol, une solution de zinc dans l'ammoniaque. On chauffe le mélange réactionnel à 80 DEG C pendant 30 minutes. Ensuite on fait une extraction dans le chlorure de méthylène. Evaporer à sec pour enlever le chlorure de méthylène, on obtient 980 g d'un produit jaune pale. On ajoute 120 ml d'acide iodohydrique à la solution obtenue, ensuite on fait passer un flux d'ozone à travers la solution. On obtient finalement 945 g d'une solution jaune pale. On fait passer cette solution à travers une colonne de chromatographie, en utilisant un mélange acétate d'éthyle et éther de pétrole (2:1) comme éluant. On a obtenu les produits suivants:
<tb><TABLE> Columns=2
<tb> <SEP>acide oxalique <SEP>100 g
<tb> <SEP>acide acétique <SEP>140 g
<tb> <SEP>acide malonique <SEP>150 g
<tb> <SEP>acide succinique <SEP>100 g
<tb> <SEP>acide adipique <SEP>250 g
<tb></TABLE>
La deuxième partie de cette invention traite le processus de réduction des produits de la dégradation de la lignine en des composés cyclohexadiényl en des acides dicarboxyliques tel que les acides oxalique, malonique, succinique et adipique. On peut utiliser le nickel de Raney comme catalyseur pour l'hydrogénation de ces composés aromatiques, ou on peut aussi les traiter par une solution d'un métal dans l'ammoniaque liquide.
Voir Figure 1
Finalement on oxyde le composé cyclohexadiényl à l'aide de l'acide chromique ou on fait une ozonolyse pour obtenir les acides dicarboxyliques. On utilise la chromatographie HPLC pour identifier ces acides carboxyliques, on a pu constater la présence de l'acide acétique.
The invention relates to the photocatalytic degradation of sulfur-free lignin, obtained by the Organosolv process, into chemical substances such as guaiacol, pyrocatechic acid, isohemipinic acid, 4-n propylguaiacol, vanillol and eugenol.
The second part of the invention deals with the reduction of the aromatic nucleus of these lignin degradation products into compounds containing a cyclohexadienyl entity. Through an oxidation process, this cyclohexadienyl entity is ultimately transformed into dicarboxylic acids, which are compounds with a variety of applications.
The main objective of this invention is to convert sulfur-free lignin into chemicals important for the organic synthesis of pharmaceutical products. Having very little commercial utility, lignin causes serious ecological and economic problems in terms of disposal. In the past, a significant amount of lignin was discharged into rivers, thus disturbing the ecological balance of the environment. Only a negligible part of the lignin was used for drilling sludge, or calcined to produce adsorbents such as activated carbon, or burnt to produce energy. Unfortunately, most of the lignin from the manufacture of paper pulp (around 200 million tonnes / year) is unused.
Thanks to the Organosolv process, sulfur-free lignin is obtained, which is easier to process.
Current methods of making pulp produce lignin which lends itself poorly to catalytic reactions: the presence of compounds such as sulphite and sulphate poison the catalysts. The lignin obtained by the Organosolv process is free of sulfur and can be degraded more effectively by the use of catalysts.
By the Organosolv process an alkaline solution of lignin is obtained; by an electrolytic process or by acidification the sodium is removed from this alkaline solution, the lignin precipitates, by centrifugation the lignin is obtained in the form of a brown powder.
The inventive process for obtaining low molecular weight compounds from sulfur-free lignin is characterized in the preceding claims.
One can either directly use said alkaline solution of lignin, or dissolve the brown powder in an organic solvent such as phenol. This mixed solution is then circulated with hydrogen peroxide (B) in a photoreactor in the presence of a catalyst such as titanium dioxide. The solution is introduced through A into the photoreactor. The advantage of this method is that a catalyst is used in the stationary phase, that is to say the titanium dioxide (T102) is deposited on a tubular filter (D). This avoids a step of filtering the catalyst at the outlet. In this configuration, the irradiation sources are composed of a halogen lamp (C) (1000 W) housed inside the tube, and two other halogen lamps (C) (2 x 1000 W) outside ; irradiation therefore takes place on the internal and external surface of the tubular filter.
Using a pump (E) the solution is circulated through the photoreactor. The flow rate of the pump is a compromise between the residence time of the solution on the catalyst necessary for the efficiency of the photocatalysis, and sufficient flow to cool the lamps. The temperature of the reaction mixture varies between 20 and 40 DEG C. A flow rate of approximately 1000 ml / min is used.
The absorption of light with an energy greater than that of the forbidden band of the semiconductor causes an electron to migrate from the valence band to the conduction band, thus creating a lack of electron in the valence band. The electrontrous pairs can recombine, or the electrons can be captured by the reducing species, or the holes by the oxidizing species. In this system, the sequence proposed for the start of photodegradation is as follows:
EMI3.1
We can make an analogy with the Fenton reagent which produces OH <+> radicals:
H2O2 + Fe <2> <+> -> OH <-> + OH <+> + Fe3 <+>
D NOTELEMENT & sqsup & & sqsub & NotEqual APPROX & anq & SIMILAR NotEqual Planck (-) NOTAPPROX & odot & APPROX & sqsub & = (-) & odot & & mstpos & NOTELEMENT & sqsup & 9 l 1/4 0 Because NOTELEMENT & sqsub & homothetic NOTELEMENT & sinew & & sinew & NOTELEMENT & prurel & & sinew & & mstpos & NotEqual & sqsup & SIMILAR & anq & & sqsup & & sqsup & & anq & = & prurel & APPROX NOTELEMENT & mstpos & NotEqual & mstpos & & anq & NOTSIMILAR & prurel & & anq & & prurel & NOTELEMENT NOTELEMENT & prurel & APPROX NOTELEMENT & sqsup & SIMILAR = homothetic BeCause = & sqsup & & uml & & sqsup & & sqsup & & anq & homothetic Because & mstpos & NOTELEMENT & sqsup & & sinew & NOTELEMENT & mstpos & & sqsup & NOTPARALLEL Planck NOTELEMENT & mstpos & NOTELEMENT guaiacol, acid protocatechuic, isohémipinique acid, 4 -n propylguaiacol, vanillol and eugenol.
The second part of this invention deals with the process of reducing the products of the degradation of lignin into cyclohexadienyl compounds and of the oxidation to dicarboxylic acids such as oxalic, malonic, succinic and adipic acids.
Raney nickel can be used as a catalyst for the hydrogenation of these aromatic compounds, or treated with a solution of a metal in liquid ammonia.
Finally, the cyclohexadienyl compound is oxidized using chromic acid, or an ozonolysis is carried out to obtain the dicarboxylic acids. HPLC chromatography is used to identify these carboxylic acids, the presence of acetic acid has been observed.
Example 1
1500 g of the alkaline solution of lignin in 150 ml of phenol are placed in a tank, then 25 ml of hydrogen peroxide are added. The solution is circulated through a photoreactor which contains a tubular filter on which a layer of titanium dioxide (10 mg / cm <3>) has been deposited. Then, the reaction mixture is irradiated using a lamp which emits in the ultraviolet (lambda max = 260 nm). Leave to react for 1 hour, then take aliquots for the following analyzes:
1) UV spectrophotometry in a range 250 nm - 350 nm, a quartz cell of 1 mm and 1 cm is used;
2) reverse phase liquid chromatography with an HPLC device. A Micropak CH-10 (octadecyl) column is used.
As eluent, a water / acetronitrile mixture is used in the proportions 65%: 35%.
<tb> <TABLE> Columns = 2
<tb> Title: Analysis results:
(% by weight per 100 g of lignin)
<tb> <SEP> guaiacol <SEP> 16%
<tb> <SEP> p-hydroxybenzaldehyde <SEP> 10%
<tb> <SEP> vanillic acid <SEP> 17%
<tb> <SEP> syringic acid <SEP> 8%
<tb> <SEP> ferrulic acid <SEP> 10%
<tb> <SEP> p-coumaric acid <SEP> 8%
<tb> <SEP> acetic acid <SEP> 10%
<tb> <SEP> carbon dioxide <SEP> 13%
<tb> <SEP> water <SEP> 5%
<tb> </TABLE>
Example 2
Experiment 1 is repeated, but the titanium dioxide is replaced by tungsten oxide. According to the analyzes, there is a small variation in the proportion of the compounds obtained.
<tb> <TABLE> Columns = 2
<tb> Title: Analysis results:
(% by weight per 100 g of lignin)
<tb> <SEP> guaiacol <SEP> 18%
<tb> <SEP> p-hydroxybenzaldehyde <SEP> 8%
<tb> <SEP> vanillic acid <SEP> 10%
<tb> <SEP> syringic acid <SEP> 11%
<tb> <SEP> ferrulic acid <SEP> 7%
<tb> <SEP> p-coumaric acid <SEP> 11%
<tb> <SEP> acetic acid <SEP> 14%
<tb> <SEP> carbon dioxide <SEP> 13%
<tb> <SEP> water <SEP> 4%
<tb> </TABLE>
Example 3
Experiment 1 is repeated again, titanium dioxide is used as catalyst, but the hydrogen peroxide is replaced by an aqueous solution of peroxodisulfate. There is also a variation in the proportion of the degradation products obtained.
<tb> <TABLE> Columns = 2
<tb> Title: Analysis results:
(% by weight per 100 g of lignin)
<tb> <SEP> guaiacol <SEP> 25%
<tb> <SEP> p-hydroxybenzaldehyde <SEP> 8%
<tb> <SEP> vanillic acid <SEP> 10%
<tb> <SEP> syringic acid <SEP> 9%
<tb> <SEP> ferrulic acid <SEP> 8%
<tb> <SEP> p-coumaric acid <SEP> 5%
<tb> <SEP> acetic acid <SEP> 12%
<tb> <SEP> carbon dioxide <SEP> 14%
<tb> <SEP> water <SEP> 6%
<tb> </TABLE>
Example 4
1000 g of guaiacol, a solution of zinc in ammonia, are mixed. The reaction mixture is heated to 80 DEG C for 30 minutes. Then an extraction is carried out in methylene chloride. Evaporate to dryness to remove the methylene chloride, 980 g of a pale yellow product are obtained. 120 ml of hydroiodic acid are added to the solution obtained, then a stream of ozone is passed through the solution. 945 g of a pale yellow solution are finally obtained. This solution is passed through a chromatography column, using a mixture of ethyl acetate and petroleum ether (2: 1) as eluent. The following products were obtained:
<tb> <TABLE> Columns = 2
<tb> <SEP> oxalic acid <SEP> 100 g
<tb> <SEP> acetic acid <SEP> 140 g
<tb> <SEP> malonic acid <SEP> 150 g
<tb> <SEP> succinic acid <SEP> 100 g
<tb> <SEP> adipic acid <SEP> 250 g
<tb> </TABLE>
The second part of this invention deals with the process of reducing the products of degradation of lignin into cyclohexadienyl compounds into dicarboxylic acids such as oxalic, malonic, succinic and adipic acids. Raney nickel can be used as a catalyst for the hydrogenation of these aromatic compounds, or they can also be treated with a solution of a metal in liquid ammonia.
See Figure 1
Finally, the cyclohexadienyl compound is oxidized using chromic acid or an ozonolysis is carried out to obtain the dicarboxylic acids. We used HPLC chromatography to identify these carboxylic acids, we could see the presence of acetic acid.
Claims (13)
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH90089A CH678857A5 (en) | 1989-03-10 | 1989-03-10 | Prodn. of low molecular wt. cpds. for pharmaceuticals - comprises degradation of sulphur free lignin by photocatalytic oxidn. |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH90089A CH678857A5 (en) | 1989-03-10 | 1989-03-10 | Prodn. of low molecular wt. cpds. for pharmaceuticals - comprises degradation of sulphur free lignin by photocatalytic oxidn. |
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| Application Number | Title | Priority Date | Filing Date |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1995025438A1 (en) * | 1994-03-21 | 1995-09-28 | Alcell Technologies Inc. | Additive for domestic animal fodder |
| CN106188164A (en) * | 2016-06-29 | 2016-12-07 | 中国矿业大学 | A kind of method of photocatalytic oxidation degradation biomass preparative organic chemistry product |
-
1989
- 1989-03-10 CH CH90089A patent/CH678857A5/en not_active IP Right Cessation
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1995025438A1 (en) * | 1994-03-21 | 1995-09-28 | Alcell Technologies Inc. | Additive for domestic animal fodder |
| CN106188164A (en) * | 2016-06-29 | 2016-12-07 | 中国矿业大学 | A kind of method of photocatalytic oxidation degradation biomass preparative organic chemistry product |
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