WO1998055684A1 - Multi-component system for modifying, decomposing or bleaching lignin, materials containing lignin or similar substances and methods for producing the same - Google Patents

Abstract

The invention relates to a multi-component system for modifying, decomposing or bleaching lignin, materials containing lignin or similar substances. Said system contains a) possibly at least one oxidation catalyst, b) at least one suitable oxidation reactant and c) at least one mediator characterized in that the mediator is chosen from the group of stable nitroxyl radicals (nitroxides).

Description

More component system for changing, breaking down or bleaching lignin, lignin-containing materials or similar substances as well as methods for their use

The present invention relates to a multi-component system for changing, breaking down or bleaching lignin, lignin-containing materials or similar substances and methods for its use.

The sulfate and sulfite processes are the main processes used today for pulp production. Both methods produce pulp under cooking and under pressure. The Sul at process works with the addition of NaOH and Na ₂ S, while Ca (HS0 ₃ ) ₂ + S0 _{2 is used} in the sulfite process, or today the sodium or ammonium salts of hydrogen sulfite are used because of their better solubility

The main aim of all processes is to remove the lignin from the plant material, wood or annual plants used.

The lignin, which is the main constituent of the plant material (stem or stem) with the cellulose and hemicellulose, must be removed, since otherwise it is not possible to produce non-yellowing and mechanically heavy-duty papers.

The wood pulp production processes work with stone grinders (wood sanding) or with refiners (TMP), which defibrillate the wood after grinding (chemical, thermal or chemical thermal).

These wood materials still contain a large part of the lignin. They are used primarily for the production of newspapers, magazines, etc. used. For some years now, the possibilities of using enzymes for lignin degradation have been researched. The mechanism of action of such lignolytic systems was only elucidated a few years ago when it was possible to obtain sufficient amounts of enzyme from the white rot fungus Phanerochaete chrysosporium through suitable cultivation conditions and inductor additives. The previously unknown lignin peroxidases and manganese peroxidases were discovered. Since Phanerochaete chrysosporium is a very effective lignin degrader, attempts were made to isolate its enzymes and to use them in purified form for lignin degradation. However, this did not succeed because it turned out that the enzymes primarily lead to a repolymerization of the lignin and not to its degradation.

The same applies to other lignolytic enzyme species such as laccases, which oxidatively break down the lignin using oxygen instead of hydrogen peroxide. It was found that similar processes occur in all cases. This is because radicals are formed which react with one another again and thus lead to polymerization.

Today there are only processes that work with in vivo systems (mushroom systems). The main focus of optimization attempts is so-called biopulping and biobleaching.

Biopulping is the treatment of wood chips with living fungal systems.

There are 2 types of application forms:

1.Pre-treatment of wood chips before refining or grinding to save energy in the production of wood materials (e.g. TMP or wood pulp).

Another advantage is the mostly existing improvement in the mechanical properties of the fabric, a disadvantage the poorer final whiteness. 2. Pretreatment of wood chips (Softwood / Hardwood) before cellulose cooking (power process, sulfite process).

The goal here is to reduce cooking chemicals, improve cooking capacity and "extended cooking".

As an advantage, improved kappa reduction after cooking compared to cooking without pretreatment is also achieved.

Disadvantages of these procedures are clearly the long treatment times (several weeks) and especially the unresolved risk of contamination during treatment if you want to forego the inefficient sterilization of the wood chips.

Biobleaching also works with in-vivo systems. The boiled pulp (Softwood / Hardwood) is inoculated with the fungus before bleaching and treated for days to weeks. Only after this long treatment time is there a significant reduction in the number of capsules and an increase in whiteness, which renders the process uneconomical for implementation in the usual bleaching sequences.

Another application that is usually carried out with immobilized fungal systems is the treatment of pulp wastewater, in particular bleaching plant wastewater to decolorize and reduce the AOX (reduction of chlorinated compounds in the wastewater that cause chlorine or chlorine dioxide bleaching stages).

In addition, it is known that hemicellulases, etc. Use xylanases, mannanases as "bleach boosters".

These enzymes are said to act primarily against the precipitated xylan, which partially covers the residual lignin after the cooking process, and through its degradation the accessibility of the lignin to those used in the subsequent bleaching sequences Increase bleaching chemicals (especially chlorine dioxide). The savings in bleaching chemicals demonstrated in the laboratory have only been partially confirmed on a large scale, so that this type of enzyme can only be classified as a bleaching additive.

Another, recently investigated possible use of lignolytic enzymes or fungi was identified in the "coal liquefaction". Preliminary investigations show the basic possibility of brown or hard coal using in vivo treatment with e.g. White mushrooms like Phanerochaete chrysosporium to attack and liquefy (incubation time several weeks) Bioengineering 4.92.8 Jg.). The possible structure of hard coal shows a three-dimensional network of polycyclic, aromatic ring systems with a "certain" similarity to lignin structures.

In addition to the lignolytic enzymes, chelating substances (siderophores such as ammonium oxalate) and biosurfactants are assumed to be the cofactor.

The application PCT / EP87 / 00635 describes a system for removing lignin from lignocellulosic material with simultaneous bleaching, which works with lignolytic enzymes from white rot fungi with the addition of reducing and oxidizing agents and phenolic compounds as mediators.

In DE 4008893C2, in addition to the Red / Ox system, "mimic substances" which simulate the active center (prosthetic group) of lignolytic enzymes are added. In this way, a significant improvement in performance could be achieved.

In the application PCT / EP92 / 01086, a redox cascade is used as an additional improvement with the aid of phenolic or non-phenolic aromatics "matched" in the oxidation potential.

The limitation for all three processes for large-scale use is the applicability with low consistency (up to a maximum of 4%) and in the last two applications there is also the risk of "leaching out" of metals when using the chelate compounds, which can lead to the destruction of the peroxide, especially in the case of downstream peroxide bleaching stages.

Methods are known from WO / 12619, WO 94/12620 and WO 94/12621 in which the activity of peroxidase is promoted by means of so-called enhancer substances.

The enhancer substances are characterized in WO 94/12619 on the basis of their half-life.

According to WO 94/12620, enhancer substances are characterized by the formula A = N-N = B, where A and B are each defined cyclic radicals.

According to WO 94/12620, enhancer substances are organic chemicals which contain at least two aromatic rings, at least one of which is substituted with defined radicals.

All three applications concern "dye transfer inhibition" and the use of the respective enhancer substances together with peroxidases as a detergent additive or detergent composition in the detergent sector. In the description of the application, reference is made to the usability for treating lignin, but our own experiments with the substances specifically disclosed in the applications showed that they had no effect as mediators for increasing the bleaching effect of the peroxidases when treating materials containing lignin!

WO 94/29510 describes a method for enzymatic delignification, in which enzymes are used together with mediators. Compounds with the structure NO, NOH or HRNOH are generally disclosed as mediators. Of the mediators listed in WO 94/29510, 1-hydroxy-1H-benzotriazole (HBT) provides the best results in delignification. However, HBT has several disadvantages:

It is only available at high prices and not in sufficient quantities.

It reacts to lH-benzotriazole under delignification conditions. This compound is relatively poorly biodegradable and can represent a considerable environmental impact in large quantities. To some extent, it causes damage to enzymes. Its delignification rate is not too high.

It is therefore desirable to provide systems for changing, breaking down or bleaching lignin, lignin-containing materials or similar substances which do not have the disadvantages mentioned or to a lesser extent.

The present invention therefore relates to a multi-component system for changing, breaking down or bleaching lignin, lignin-containing materials or similar substances

a. optionally at least one oxidation catalyst and

b. at least one suitable oxidizing agent and

c. at least one mediator, characterized in that the mediator is selected from the group of stable nitroxyl radicals (nitroxides).

In the context of the invention, a stable nitroxyl radical (nitroxide) is to be understood as meaning that these free radicals can be obtained, characterized and stored in pure form.

It has now been found that the multicomponent system according to the invention with mediators selected from the class of stable nitroxyl radicals does not have the disadvantages of the multicomponent systems known from the prior art.

Preferred mediators in the multicomponent system according to the invention are compounds of the general formula (I), (II) or (III)

(I) (II) (III)

in which

Ar is monovalent homo- or heteroaromatic mono- or dinuclear radical, and this aromatic radical is selected by one or more, identical or different radicals R ² selected from the group consisting of halogen, formyl, cyano, carbamoyl, carboxy, ester or salt of carboxy, sulfone, ester or salt of sulfone, sulfamoyl, nitro, nitroso, amino, phenyl,

, C,-C₁₀-Carbonyl- ,

, Phospho-, Phosphono-, Phosphonooxyrest , Ester oder Salz des Phosphonooxyrests substituiert sein können und wobei Phenyl-, Carbamoyl- und Sulfamoylreste unsubstituiert oder ein- oder mehrfach mit einem Rest R³ substituiert sein können, der Aminorest ein- oder zweifach mit R³ substituiert sein kann und die

, C.,-C₅-Alkoxy- , C,-C₁₀-Carbonyl- ,

gesättigt oder unge- sättigt, verzweigt oder unverzweigt sein können und mit einem Rest R³ ein- oder mehrfach substituiert sein können, wobei R³ ein- oder mehrfach vorhanden sein kann und gleich oder verschieden ist und Hydroxy- , Formyl-, Cyano-, Carboxyrest, Ester oder Salz des Carboxyrests, Carbamoyl-, Sulfono-, Sulfamoyl-, Nitro-, Nitroso-, Amino-, Phenyl-, C₁-C₅-Alkyl- , C^C_j-Alkoxy- , C^C_j-Alkylcarbonylrest bedeutet undAryl-C, -C ₅ -alkyl-, C, -C ₁₂ -alkyl-,

, C, -C ₁₀ carbonyl,

, Phospho, phosphono, phosphonooxy, ester or salt of the phosphonooxy may be substituted and where phenyl, carbamoyl and sulfamoyl residues may be unsubstituted or substituted one or more times with a residue R ³ , the amino residue one or two times with R ³ can be substituted and the

, C., - C ₅ -alkoxy-, C, -C ₁₀ -carbonyl-,

can be saturated or unsaturated, branched or unbranched and can be substituted one or more times with a radical R ³ , where R ³ can be present one or more times and is the same or different and hydroxyl, formyl, cyano, carboxy, ester or salt of carboxy, carbamoyl, sulfono, sulfamoyl, nitro, nitroso, amino, phenyl , C ₁ -C ₅ alkyl, C ^ C _j -alkoxy-, C ^ C _j -alkylcarbonyl radical and

, Phospho-, Phosphono-, Phosphono-oxyrest , Ester oder Salz des Phosphonooxyrests bedeutet und R¹ im Fall bicyclischer stabiler Nitroxylradikale (StrukturR ^{1 is the} same or different and is halogen, hydroxyl, mercapto, formyl, cyano, carbamoyl, carboxy, ester or salt of carboxy, sulfono, ester or salt of sulfono, sulfamoyl, nitro , Nitroso, amino, phenyl, aryl - C, -C ₅ alkyl -, C, -C ₁₂ alkyl -,

, Phospho, phosphono, phosphonooxy residue, ester or salt of the phosphonooxy residue means and R ¹ in the case of bicyclic stable nitroxyl radicals (structure

,

gesättigt oder ungesättigt, verzweigt oder unverzweigt sein können und mit einem Rest R⁴ ein- oder mehrfach substituiert sein können, wobei R⁴ gleich oder verschieden ist und Hydroxy-, Formyl-, Cyano-, Carboxyrest, Ester oder Salz des Carboxyrests, Carbamoyl-, Sulfono-, Sulfamoyl-, Nitro-, Nitroso-, Amino, Phenyl-, C^C₃-Alkyl-, C, - C₆-Alkoxyrest , C, - C₅-Alkylcarbonylrest bedeutet und je zwei Reste R³oder R⁴ paarweise über eine Brücke [-CR⁶R⁶-] _mmit m gleich 0,1,2,3 oder 4 verknüpft sein können undIII) can also be hydrogen and carbamoyl, sulfamoyl, amino, mercapto and phenyl radicals can be unsubstituted or substituted one or more times with a radical R ⁴ and the aryl -C, -C ₅ -alkyl-, C, -C ₁₂ alkyl,

.

can be saturated or unsaturated, branched or unbranched and can be substituted one or more times with a radical R ⁴ , where R ^{4 is} identical or different and is hydroxyl, formyl, cyano, carboxy, ester or salt of carboxy, carbamoyl, , Sulfono, sulfamoyl, nitro, nitroso, amino, phenyl, C ^ C ₃ alkyl, C, - C ₆ alkoxy radical, C, - C ₅ alkylcarbonyl radical and two radicals R ³ or R each ⁴ can be linked in pairs over a bridge [-CR ⁶ R ⁶ -] _m with m equal to 0, 1, 2, 3 or 4 and

R ⁵ and R ^{6 are the} same or different and halogen, carboxy, ester or salt of carboxy, carbamoyl, sulfamoyl, phenyl, benzoyl, C, -C ₅ alkyl, C, -C ₅ alkoxy , C., - C ₆ alkylcarbonyl radical and one or more non-adjacent groups [-CR ⁵ R ⁶ -] by oxygen, sulfur or an imino residue which is optionally substituted by C 1 -C ₅ -alkyl and two adjacent groups [-CR ⁵ R ⁶ -] by one Group [-CR ⁵ = CR ⁶ -], [-CR ⁵ = N-] or [-CR ^δ = N (0) -] can be replaced.

Particularly preferred mediators in the multicomponent system according to the invention are nitroxyl radicals of the general formulas (IV) and (V),

(IV) (V)

in which

,

bedeutet wobei Phenylreste unsubstituiert oder ein- oder mehrfach mit einem Rest R⁹ substituiert sein können und die

,

gesättigt oder ungesättigt, verzweigt oder unverzweigt sein können und mit einem Rest R⁹ ein- oder mehrfach substituiert sein können, wobei R⁹ ein- oder mehrfach vorhanden sein kann und gleich oder verschieden ist und Hydroxy-, Formyl-, Carboxyrest, Ester oder Salz des Carboxyrests, Carbamoyl-, Sulfono-, Sulfamoyl-, Nitro-, Nitroso-, Amino, Phenyl-, Benzoyl-,

, C, - C₅-Alkxyrest, C, - C₅-Alkylcarbonylrest bedeutet und R⁸ gleich oder verschieden ist und Wasserstoff-, Hydroxy-, Mer- capto-, Formyl-, Cyano-, Carbamoyl-, Carboxyrest, Ester oder Salz des Carboxyrests, Sulfonorest, Ester oder Salz des Sulfo- norests, Sulfamoyl-, Nitro-, Nitroso-, Amino-, Phenyl-, Aryl

, Carbonyl

- , Phospho-, Phosphono-, Phosphonooxyrest , Ester oder Salz des Phosphono-oxyrests bedeutet wobei Carbamoyl-, Sulfamoyl-, Amino-, Mercapto- und Phenylre- ste unsubstituiert oder ein- oder mehrfach mit einem Rest R³ substituiert sein können und die Aryl-C^C_j-alkyl- ,

R ^{7 is the} same or different and is phenyl, aryl, C ₅ -C ₅ alkyl, C ₁₂ -C ₁₂ alkyl,

.

means where phenyl radicals can be unsubstituted or substituted one or more times with a radical R ⁹ and the

.

can be saturated or unsaturated, branched or unbranched and can be substituted one or more times with a radical R ⁹ , where R ⁹ can be present one or more times and is the same or different and hydroxyl, formyl, carboxy, ester or salt of carboxy, carbamoyl, sulfono, sulfamoyl, nitro, nitroso, amino, phenyl, benzoyl,

, C, - C ₅ alkoxy radical, C, - C ₅ alkylcarbonyl radical and R ^{8 is the} same or different and is hydrogen, hydroxyl, mercapto, formyl, cyano, carbamoyl, carboxy, ester or salt of carboxy, sulfono, ester or salt of sulfo, sulfamoyl, nitro , Nitroso, amino, phenyl, aryl

, Carbonyl

-, Phospho-, Phosphono-, Phosphonooxy residue, ester or salt of the phosphono-oxy residue means wherein carbamoyl, sulfamoyl, amino, mercapto and phenyl residues can be unsubstituted or substituted one or more times with a radical R ³ and the Aryl-C ^ C _j -alkyl-,

substituierten Iminorest, einen (Hydroxy) imino- rest, eine Carbonylfunktion oder eine ggf. mit R³mono- oder disubstituierten Vinylidenfunktion ersetzt sein kann und zwei benachbarte Gruppen [-CR⁸R⁸-] durch eine Gruppe [-CR⁸=CR⁸-] oder [-CR⁸=N-] oder [-CR⁸=N(0)-] ersetzt sein können.Carbonyl-C, -C ₆ -alkyl radicals can be saturated or unsaturated, branched or unbranched and can be substituted one or more times with a radical R ³ and a [-CR ⁸ R ⁸ -] group by oxygen, a possibly . With

substituted imino residue, a (hydroxy) imino residue, a carbonyl function or a vinylidene function which may be mono- or disubstituted with R ³ , and two adjacent groups [-CR ⁸ R ⁸ -] can be replaced by a group [-CR ⁸ = CR ⁸ -] or [-CR ⁸ = N-] or [-CR ⁸ = N (0) -] can be replaced.

Examples of compounds which can be used as mediators (component c) in the multicomponent system according to the invention are

2, 2, 6, 6 -tetramethyl-piperidine-1-oxyl (TEMPO), 4 -hydroxy-2, 2,6, 6-tetramethyl-piperidine-1-oxyl, 4-0x0-2, 2,6, 6 -tetramethyl-piperidine-l-oxyl, 4-acetamido-2, 2,6, 6-tetramethyl-piperidine-l-oxyl, 4- (ethoxyfluorophosphinyloxy) -2,2,6, 6-tetramethyl-piperidine-lo xyl, 4- (isothiocyanato) -2,2,6, 6-tetramethyl-piperidine-l-oxyl, 4-maleimido-2, 2,6, 6-tetramethyl-piperidine-l-oxyl, 4- (4-nitrobenzoyloxy) - 2,2,6,6-tetramethyl-piperidine-l-oxyl, 4- (phosphonooxy) -2,2,6,6-tetramethyl-piperidine-l-oxyl, 4-cyano-2, 2,6,6- tetramethyl-piperidine-l-oxyl,

3-carbamoyl -2, 2,5, 5-tetramethyl-3-pyrroline-l-oxyl,

4-phenyl -2, 2,5, 5-tetramethyl-3-imidazoline-3-oxide-l-oxyl,

4-carbamoyl -2, 2,5, 5-tetramethyl-3-imidazoline-3-oxide-l-oxyl, 4-phenacylidene-2, 2,5, 5-tetramethyl-imidazolidin-l-oxyl, 3- (aminomethyl) -2,2,5, 5-tetramethyl-pyrrolidine-N-oxyl, 3-carbamoyl -2, 2, 5, 5-tetramethyl-pyrrolidine-N-oxyl, 3-carboxy-2, 2.5, 5-tetramethyl-pyrrolidine-N-oxyl, 3-cyano-2, 2.5, 5-tetramethyl-pyrrolidine-N- oxyl,

3-maleimido-2, 2,5, 5-tetramethyl-pyrrolidine-N-oxyl,

3- (4-nitrophenoxycarbonyl) -2,2,5,5-tetramethyl-pyrrolidin-N-ox yi-

Preferred mediators are preferred

2, 2, 6, 6-tetramethyl-piperidine-1-oxyl (TEMPO), 4-hydroxy-2, 2,6, 6-tetramethyl-piperidine-1-oxyl, 4-oxo-2, 2,6, 6 -tetramethyl-piperidine-l-oxyl, 4-acetamido-2, 2,6, 6-tetramethyl-piperidine-l-oxyl, 4- (isothiocyanato) -2,2,6, 6-tetramethyl-piperidine-l-oxyl , 4-maleimido-2, 2,6, 6-tetramethyl-piperidine-l-oxyl, 4- (4-nitrobenzoyloxy) -2,2,6, 6-tetramethyl-piperidine-l-oxyl, 4- (phosphonooxy) -2,2,6, 6-tetramethyl-piperidine-l-oxyl, 4-cyano-2, 2,6, 6-tetramethyl-piperidine-l-oxyl, 3-carbamoyl-2, 2,5, 5-tetramethyl -3-pyrroline-l-oxyl,

4-phenyl -2, 2,5, 5-tetramethyl-3-imidazoline-3-oxide-1-oxyl,

4-carbamoyl -2, 2,5, 5-tetramethyl-3-imidazoline-3-oxide-l-oxyl,

4-phenacylidene-2, 2,5, 5-tetramethyl-imidazolidine-l-oxyl.

As mediators are particularly preferred

2, 2, 6, 6-tetramethyl-piperidine-1-oxyl (TEMPO), and 4-hydroxy-2, 2,6, 6-tetramethyl-piperidine-1-oxyl.

The multicomponent system according to the invention contains mediators which have the following advantages, in particular to the mediators (in particular HOBT) which are known from the prior art:

1) The typical formation of colored reactants known for these substances (especially HOBT) is not or only very weakly present, which can be of great advantage for the application.

2) The response speed is generally faster.

3) The degradability is sometimes much better. The multicomponent system according to the invention preferably comprises at least one oxidation catalyst.

Enzymes are preferably used as oxidation catalysts in the multi-component system according to the invention. For the purposes of the invention, the term enzyme also encompasses enzymatically active proteins or peptides or prosthetic groups of enzymes.

Oxidoreductases of classes 1.1.1 to 1.97 according to the International Enzyme Nomenclature, Committee of the International Union of Biochemistry and Molecular Biology (Enzyme Nomenclature, Academic Press, Inc., 1992, pp. 24-154) can be used as the enzyme in the multicomponent system according to the invention .

Enzymes of the classes mentioned below are preferably used:

Class 1.1 enzymes, which comprise all dehydrogenases which act on primary, secondary alcohols and semiacetals, and which are accepted as NAD ⁺ or NADP ⁺ (subclass 1.1.1), cytochrome (1.1.2), oxygen (0 ₂ ) (1.1.3), disulfides (1.1.4), quinones (1.1.5) or the other acceptors (1.1.99).

From this class, the enzymes of class 1.1.5 with quinones as acceptors and the enzymes of class 1.1.3 with oxygen as acceptors are particularly preferred.

Cellobiose: quinone-1-oxidoreductase (1.1.5.1) is particularly preferred in this class.

Enzymes of class 1.2 are also preferred. This class of enzymes includes those enzymes that oxidize aldehydes to the corresponding acids or oxo groups. The acceptors can be NAD ⁺ , NADP ⁺ (1.2.1), cytochrome (1.2.2), oxygen (1.2.3), sulfides (1.2.4), iron-sulfur proteins (1.2.5) or other acceptors (1.2 .99). The enzymes of group (1.2.3) with oxygen as the acceptor are particularly preferred here.

Enzymes of class 1.3 are also preferred.

This class includes enzymes that act on the CH-CH groups of the donor.

The corresponding acceptors are NAD ⁺ , NADP ⁺ (1.3.1), cytochrome (1.3.2), oxygen (1.3.3), quinones or related compounds (1.3.5), iron-sulfur proteins (1.3.7 ) or other acceptors (1.3.99).

Bilirubin oxidase (1.3.3.5) is particularly preferred.

The enzymes of class (1.3.3) with oxygen as acceptor and (1.3.5) with quinones etc. as acceptor are also particularly preferred here.

Enzymes of class 1.4 which are based on

CH-NH ₂ groups of the donor act.

The corresponding acceptors are NAD ⁺ , NADP ⁺ (1.4.1), cytochrome (1.4.2), oxygen (1.4.3), disulfides (1.4.4), iron-sulfur proteins (1.4.7) or others Acceptors (1.4.99).

Enzymes of class 1.4.3 with oxygen as the acceptor are also particularly preferred here.

Also preferred are class 1.5 enzymes based on CH-NH-

Groups of the donor work. The corresponding acceptors are NAD ⁺ , NADP ⁺ (1.5.1), oxygen (1.5.3), disulfides (1.5.4), quinones (1.5.5) or other acceptors (1.5.99).

Here too, enzymes with oxygen (02) (1.5.3) and with quinones (1.5.5) are particularly preferred as acceptors. Enzymes of class 1.6 which act on NADH or NADPH are also preferred.

The acceptors here are NADP ⁺ (1.6.1), heme proteins (1.6.2), disulfides (1.6.4), quinones (1.6.5), N0 ₂ groups (1.6.6), and a flavin (1.6.8 ) or some other acceptors (1.6.99).

Enzymes of class 1.6.5 with quinones as acceptors are particularly preferred here.

Also preferred are class 1.7 enzymes which act as donors on other N02 compounds and acceptors cytochrome (1.7.2), oxygen (0 ₂ ) (1.7.3), iron-sulfur proteins (1.7.7) or others (1.7.99).

Class 1.7.3 with oxygen as the acceptor is particularly preferred here.

Also preferred are class 1.8 enzymes which act as donors on sulfur groups and NAD ⁺ , NADP ⁺ as acceptors

(1.8.1), cytochrome (1.8.2), oxygen (0 ₂ ) (1.8.3), disulfide (1.8.4), quinones (1.8.5), iron-sulfur proteins (1.8.7) or others (1.8.99).

Class 1.8.3 with oxygen (0 ₂ ) and (1.8.5) with quinones as acceptors is particularly preferred.

Also preferred are class 1.9 enzymes which act as donors on heme groups and have oxygen (0 ₂ ) (1.9.3), NO ₂ compounds (1.9.6) and others (1.9.99) as acceptors.

Group 1.9.3 with oxygen (0 ₂ ) as acceptor (cytochrome oxidases) is particularly preferred here.

Also preferred are class 1.12 enzymes which act on hydrogen as a donor. The acceptors are NAD ⁺ or NADP ⁺ (1.12.1) or others (1.12.99).

Enzymes of class 1.13 and 1.14 (oxigenases) are also preferred.

Preferred enzymes are also those of class 1.15 which act as acceptors on superoxide radicals.

Superoxide dismutase (1.15.1.1) is particularly preferred here.

Enzymes of class 1.16 are also preferred.

NAD ⁺ or NADP ⁺ (1.16.1) or oxygen (02) (1.16.3) act as acceptors.

Enzymes of class 1.16.3.1 (ferroxidase, e.g. ceruloplasmin) are particularly preferred here.

Further preferred enzymes are those belonging to the group

1.17 (effect on CH2 groups which are oxidized to -CHOH-),

1.18 (effect on reduced ferredoxin as donor), 1.19 (effect on reduced flavodoxin as donor) and 1.97 (other oxidoreductases).

The enzymes of group 1.11 are also particularly preferred. which act on a peroxide as an acceptor. This only subclass (1.11.1) contains the peroxidases.

The cytochrome C peroxidases are particularly preferred here

(1.11.1.5), Catalase (1.11.1.6), the peroxidase (1.11.1.6), the iodide peroxidase (1.11.1.8), the glutathione peroxidase

(1.11.1.9), the chloride peroxidase (1.11.1.10), the L-ascorbate peroxidase (1.11.1.11), the phospholipid hydroperoxide

Glutathione peroxidase (1.11.1.12), the manganese peroxidase

(1.12.1.13), the diarylpropane peroxidase (ligninase, lignin peroxidase) (1.11.1.14). Enzymes of class 1.10 which act on biphenols and related compounds are very particularly preferred. They catalyze the oxidation of biphenols and ascorbates. NAD ⁺ , NADP ⁺ (1.10.1), cytochrome (1.10.2), oxygen (1.10.3) or others (1.10.99) act as acceptors.

Of these in turn, class 1.10.3 enzymes with oxygen (0 ₂ ) as the acceptor are particularly preferred.

Of the enzymes in this class, the enzymes are catechol oxidase (tyrosinase) (1.10.3.1), L-ascorbate oxidase (1.10.3.3), o-aminophenol oxidase (1.10.3.4) and laccase (benzenediol: oxigen oxidoreductase) (1.10 .3.2) is preferred, the laccases (benzene diol: oxigen oxidoreductase) (1.10.3.2) being particularly preferred.

The enzymes mentioned are commercially available or can be obtained by standard methods. Plants, animal cells, bacteria and fungi, for example, come into consideration as organisms for the production of the enzymes. Basically, both naturally occurring and genetically modified organisms can be enzyme producers. Parts of unicellular or multicellular organisms are also conceivable as enzyme producers, especially cell cultures.

White rot fungi such as pleurotus, phlebia and trametes are used, for example, for the particularly preferred enzymes, such as those from group 1.11.1, but especially 1.10.3, and in particular for the production of laccases.

The multi-component system according to the invention comprises at least one oxidizing agent. Examples of oxidizing agents that can be used are air, oxygen, ozone, peroxides, such as H ₂ O _2, and organic peroxides, peracids, such as peracetic acid, performic acid, persulfuric acid, persalpic acid, metachloroperoxobenzoic acid, perchloric acid, and other “per compounds”, such as perborates, peracetates, persulfates or oxygen species and their radicals, such as OH-, OOH ", singlet oxygen, superoxide (0 ₂ ^~ ), ozonide, dioxygenyl cation (0 ₂ ⁺ ), dioxiranes, dioxetanes or fremy radicals can be used.

Preferably oxidizing agents are used which can either be generated by the corresponding oxidoreductases e.g. Dioxiranes from laccases plus carbonyls or which chemically regenerate the mediator or can directly implement it.

The invention also relates to the use of substances which, according to the invention, are suitable as mediators for changing, breaking down or bleaching lignin, lignin-containing materials or similar substances.

The effectiveness of the multi-component system when changing, breaking down or bleaching lignin, lignin-containing materials or similar substances is often further increased if Mg ²⁺ ions are present in addition to the components mentioned. The Mg ²⁺ ions can be used, for example, as a salt, such as MgS0 ₄ . The concentration is in the range of 0.1-2 ^m g / lignin-containing material, preferably 0.2-0.6 mg / g.

In some cases a further increase in the effectiveness of the multicomponent system according to the invention can be achieved in that the multicomponent system in addition to the Mg ²⁺ ions also complexing agents such as, for example, ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), hydroxyethylenediamine triacetic acid (HEDTA), Contains diethylenetriaminepentamethylenephosphonic acid (DTPPA), nitrilotriacetic acid (NTA), polyphosphoric acid (PPA) etc. The concentration is in the range of 0.2-5 mg / g of lignin-containing material, preferably 1-3 mg.

The use of the multicomponent system according to the invention in a process for treating lignin takes place, for example, in that the components a) to c) selected in each case mixes simultaneously or in any order with an aqueous suspension of the lignin-containing material.

A method using the multicomponent system according to the invention is preferably used in the presence of oxygen or air at atmospheric pressure up to 10 bar and in a pH range from 2 to 11, at a temperature of 20 to 95 ° C., preferably 40-95 ° C. and a consistency of 0.5 to 40%.

A finding that is unusual and surprising for the use of enzymes in pulp bleaching is that when the multicomponent system according to the invention is used an increase in the consistency enables a significant increase in the kappa reduction.

For economic reasons, a process according to the invention is preferably carried out at consistencies of 8 to 35%, particularly preferably 9 to 15%.

Surprisingly, it was also found that an acidic wash (pH 2 to 6, preferably 4 to 5) or Q stage (pH 2 to 6, preferably 4 to 5) before the enzyme mediator stage in some pulps led to a considerable reduction in the kappa number Comparison to treatment without this special pretreatment leads. The substances used for this purpose (such as EDTA, DTPA) are used as chelating agents in the Q stage. They are preferably used in concentrations of 0.1% to 1% (w / w based on dry cellulose), particularly preferably 0.1% to 0.5% (w / w based on dry cellulose).

0.01 to 100 IU enzyme per g lignin-containing material are preferably used in the process according to the invention. 0.1 to 100 IU of enzyme per g of lignin-containing material are particularly preferably used (1 U corresponds to the conversion of 1 μmol

2,2'-Azino-bis (3-ethyl-benzothiazoline-6-sulfonic acid diammonium salt) (ABTS) / min / ml enzyme. In the process according to the invention, preferably 0.01 mg to 100 mg of oxidizing agent are used per g of lignin-containing material. 0.01 to 50 mg of oxidizing agent per g of lignin-containing material are particularly preferably used.

In the method according to the invention, 0.5 to 80 mg of mediator per g of lignin-containing material is preferably used. 0.5 to 40 mg of mediator per g of lignin-containing material is particularly preferably used.

At the same time, reducing agents can be added which, together with the oxidizing agents present, serve to set a certain redox potential.

Sodium bisulfite, sodium dithionite, ascorbic acid, thio compounds, mercapto compounds or glutathione etc. can be used as reducing agents.

In the case of laccase, for example, the reaction takes place with air or oxygen supply or air or oxygen overpressure, with the peroxidases (e.g. lignin peroxidases, manganese peroxidases) with hydrogen peroxide. For example, the oxygen can also be generated in situ by hydrogen peroxide + catalase and hydrogen peroxide by glucose + GOD or other systems.

In addition, radical formers or radical scavengers (trapping, for example, OH or OOH radicals) can be added to the system. These can improve the interaction within the Red / Ox and radical mediators.

Other metal salts can also be added to the reaction solution. These are important in conjunction with chelating agents as radical formers or red / ox centers. The salts form cations in the reaction solution. Such ions include Fe ²⁺ , Fe ³⁺ , Mn ²⁺ , Mn ³⁺ , Mn ⁴⁺ , Cu ²⁺ , Ca ²⁺ , Ti ³⁺ , Cer ⁴⁺ , Al ³⁺ . The chelates present in the solution can also serve as mimic substances for the enzymes, for example for the laccases (copper complexes) or for the lignin or manganese peroxidases (heme complexes). Mimic substances are substances that simulate the prosthetic groups of (here) oxidoreductases and can catalyze oxidation reactions, for example.

NaOCl can also be added to the reaction mixture. In combination with hydrogen peroxide, this compound can form singlet oxygen.

Finally, it is also possible to work using detergents. Non-ionic, anionic, cationic and amphoteric surfactants come into consideration as such. The detergents can improve the penetration of the enzymes and mediators into the fiber.

It may also be beneficial for the reaction to add polysaccharides and / or proteins. Glucans, mannans, dextrans, levans, pectins, alginates or plant gums and / or own polysaccharides formed by the fungi or produced in the mixed culture with yeasts and in particular gelatin and albumin are to be mentioned here as polysaccharides. These substances mainly serve as protective colloids for the enzymes.

Other proteins that can be added are proteases such as pepsin, bromelin, papain, etc. These can include serve to achieve better access to lignin by breaking down the extensin C (hydroxyproline-rich protein) present in the wood.

Amino acids, simple sugar, oligomer sugar, PEG types of the most varied molecular weights, polyethylene oxides, polyethyleneimines and polydimethylsiloxanes can be considered as further protective colloids. The process according to the invention can be used not only in the delignification (bleaching) of sulfate, sulfite, organosol, or the like wood pulp and also in the production of wood pulp, but also in the production of cellulose in general, whether from wood or annual plants, if defibrillation through the usual cooking processes (possibly connected with mechanical processes or pressure), ie very gentle cooking up to capa numbers, which can be in the range of approx. 50-120 kappa, is guaranteed.

In the bleaching of cellulose as well as in the production of cellulose, the treatment can be repeated several times, either after washing and extraction of the treated material with NaOH or without these intermediate steps. This leads to kappa values which can be reduced still further and to substantial increases in whiteness. Likewise, a 0 ₂ stage can be used before the enzyme / mediator treatment or, as already mentioned, an acid wash or Q stage (chelate stage) can be carried out.

A similar procedure is used for the "liquefaction" of coal (hard coal, lignite) as for the delignification (bleaching) of wood or annual plant pulp.

The invention is explained in more detail below with the aid of examples:

example 1

Enzymatic bleaching with 4-hydroxy-2, 2, 6, 6-tetramethylpiperidine-1-oxyl and Softwood sulfate pulp

5 g dry cellulose (Softwood 0 ₂ delignified), consistency 30% (approx. 17 g wet) are added to the following solutions:

A) 20 ml tap water with 63.8 mg

4-Hydroxy-2, 2, 6, 6-tetramethylpiperidine-1-oxyl mixed with stirring, the pH with 0.5 mol / 1 H2S04 solution. set so that after adding the pulp and the enzyme pH 4.5 results.

B) 5 ml of tap water are mixed with the amount of Laccase from Trame- tes versicolor that an activity of 15 U (1 U = conversion of 1 μmol ABTS / min / ml enzyme) results per g of pulp.

Solutions A and B are added together and made up to 33 ml.

After adding the pulp, mix with a dough kneader for 2 min.

The substance is then placed in a reaction bomb preheated to 45 ° C. and incubated under 1-10 bar oxygen pressure for 1-4 hours.

The material is then washed over a nylon sieve (30 μm) and extracted for 1 hour at 60 ° C., 2% consistency and 8% NaOH per g of pulp.

After washing the fabric again, the kappa number is determined.

Result cf. Table 1

Example 2

Enzymatic bleaching with 4-phenyl-2, 2, 5, 5-tetramethylimidazoline-3-oxide-l-oxyl and Softwood sulfate pulp

5 g dry cellulose (Softwood 0 ₂ delignified), consistency 30% (approx. 17 g wet) are added to the following solutions:

A) 20 ml tap water with 81.5 mg

4-phenyl -2, 2,5, 5-tetramethylimidazoline-3-oxide-l-oxyl under

Stir added, the pH value with 0.5 mol / 1 H ₂ S0 ₄ solution. so adjusted that pH 4.5 results after addition of the pulp and the enzyme.

B) 5 ml of tap water are mixed with the amount of Laccase from Trame- tes versicolor that an activity of 15 U (1 U = conversion of 1 μmol ABTS / min / ml enzyme) results per g of pulp.

Solutions A and B are added together and made up to 33 ml.

After adding the pulp, mix with a dough kneader for 2 min.

The substance is then placed in a reaction bomb preheated to 45 ° C. and incubated under 1-10 bar oxygen pressure for 1-4 hours.

The fabric is then washed over a nylon sieve (30 μm) and extracted for 1 hour at 60 ° C., 2% fabric density and 8% NaOH per g of pulp.

After washing the fabric again, the kappa number is determined.

Result cf. Table 1

Example 3

Enzymatic bleaching with 4-oxo-2, 2, 6, 6-tetramethylpiperidine-1-oxyl and Softwood sulfate pulp

5 g dry cellulose (Softwood 0 ₂ delignified), consistency 30% (approx. 17 g wet) are added to the following solutions:

A) 20 ml tap water with 63.9 mg

4-Oxo-2, 2, 6, 6-tetramethylpiperidine-l-oxyl with stirring added, the pH with 0.5 mol / 1 H ₂ S0 ₄ solution. adjusted so that pH 4.5 results after addition of the pulp and the enzyme.

B) 5 ml of tap water are mixed with the amount of Laccase from Trame- tes versicolor that an activity of 15 U (1 U = conversion of 1 μmol ABTS / min / ml enzyme) results per g of pulp.

Solutions A and B are added together and made up to 33 ml.

After adding the pulp, mix with a dough kneader for 2 min.

The substance is then placed in a reaction bomb preheated to 45 ° C and incubated under 1-10 bar oxygen pressure for 1-4 hours.

The material is then washed over a nylon sieve (30 μm) and extracted for 1 hour at 60 ° C., 2% consistency and 8% NaOH per g of pulp.

After washing the fabric again, the kappa number is determined.

Result cf. Table 1

Example 4

Enzy atic bleach with

4-cyano-2, 2, 6, 6-tetramethylpiperidine-1-oxyl and Softwood

Sulphate fabric

5 g dry cellulose (Softwood 0 ₂ delignified), consistency 30% (approx. 17 g wet) are added to the following solutions:

A) 20 ml tap water with 68.0 mg

4-cyano-2, 2, 6, 6-tetramethylpiperidine-1-oxyl added with stirring, the pH with 0.5 mol / 1 H ₂ S0 ₄ solution. adjusted so that pH 4.5 results after addition of the pulp and the enzyme.

B) 5 ml of tap water are mixed with the amount of Laccase from Trame- tes versicolor that an activity of 15 U (1 U = conversion of 1 μmol ABTS / min / ml enzyme) results per g of pulp.

Solutions A and B are added together and made up to 33 ml.

After adding the pulp, mix with a dough kneader for 2 min.

The substance is then placed in a reaction bomb preheated to 45 ° C. and incubated under 1-10 bar oxygen pressure for 1-4 hours.

The material is then washed over a nylon sieve (30 μm) and extracted for 1 hour at 60 ° C., 2% consistency and 8% NaOH per g of pulp.

After washing the fabric again, the kappa number is determined.

Result cf. Table 1 Example 5

Enzymatic bleach with 2, 2, 6, 6-tetramethylpiperidine-1-oxyl and Softwood sulfate pulp

5 g dry cellulose (Softwood 0 ₂ delignified), consistency 30% (approx. 17 g wet) are added to the following solutions:

A) 20 ml of tap water are mixed with 57.8 mg of 2, 2, 6, 6-tetramethylpiperidine-1-oxyl with stirring, the pH with 0.5 mol / 1 H ₂ S0 ₄ solution. adjusted so that pH 4.5 results after addition of the pulp and the enzyme.

B) 5 ml of tap water are mixed with the amount of Laccase from Trameses versicolor that an activity of 15 U (1 U =

Conversion of 1 μmol ABTS / min / ml enzyme) per g of pulp results.

Solutions A and B are added together and made up to 33 ml.

After adding the pulp, mix with a dough kneader for 2 min.

The substance is then placed in a reaction bomb preheated to 45 ° C. and incubated under 1-10 bar oxygen pressure for 1-4 hours.

The fabric is then washed over a nylon sieve (30 μm) and extracted for 1 hour at 60 ° C., 2% fabric density and 8% NaOH per g of pulp.

After washing the fabric again, the kappa number is determined.

Result cf. Table 1 Example 6

Enzymatic bleaching with 4-acetamido-2, 2, 6, 6-tetramethyl-piperidin-1-oxyl and Softwood sulfate pulp

5 g dry cellulose (Softwood 02 delignified), consistency

30% (approx. 17 g moist) are added to the following solutions:

A) 20 ml of tap water are mixed with 79.0 mg of 4-acetamido-2, 2, 6, 6-tetramethylpiperidine-1-oxyl with stirring, the pH with 0.5 mol / 1 H ₂ S0 ₄ ~ solution. adjusted so that pH 4.5 results after addition of the pulp and the enzyme.

B) 5 ml of tap water are mixed with the amount of Laccase from Trame- tes versicolor that an activity of 15 U (1 U = conversion of 1 μmol ABTS / min / ml enzyme) results per g of pulp.

Solutions A and B are added together and made up to 33 ml.

After adding the pulp, mix with a dough kneader for 2 min.

Then the substance is placed in a reaction bomb preheated to 45 ° C and under 1 - 10 bar oxygen pressure for 1 -

Incubated for 4 hours.

The material is then washed over a nylon sieve (30 μm) and extracted for 1 hour at 60 ° C., 2% consistency and 8% NaOH per g of pulp.

After washing the fabric again, the kappa number is determined

Result cf. Table 1 Example 7

Enzyme bleach with 4-carbamoyl-2, 2, 5, 5-tetramethyl-3-imidazoline-3-oxide-1-oxyl and Softwood sulfate pulp

5 g dry cellulose (Softwood 0 ₂ delignified), consistency 30% (approx. 17 g wet) are added to the following solutions:

A) 20 ml of tap water are mixed with 74.0 mg of 4-carbamoyl -2, 2,5, 5-tetramethyl-3-imidazoline-3-oxide-l-oxyl with stirring, the pH with 0.5 mol / 1 H ₂ S0 ₄ solution. adjusted so that pH 4.5 results after addition of the pulp and the enzyme.

B) 5 ml of tap water are mixed with the amount of Laccase from Trame- tes versicolor that an activity of 15 U (1 U = conversion of 1 μmol ABTS / min / ml enzyme) results per g of pulp.

Solutions A and B are added together and made up to 33 ml.

After adding the pulp, mix with a dough kneader for 2 min.

The substance is then placed in a reaction bomb preheated to 45 ° C. and incubated under 1-10 bar oxygen pressure for 1-4 hours.

The material is then washed over a nylon sieve (30 μm) and extracted for 1 hour at 60 ° C., 2% consistency and 8% NaOH per g of pulp.

After washing the fabric again, the kappa number is determined.

Result cf. Table 1 Example 8

Enzymatic bleaching with 3-carbamoyl-2, 2, 5, 5-tetramethyl-

3-pyrroline-l-oxyl and softwood sulfate pulp

5 g dry cellulose (Softwood 0 ₂ delignified), consistency

30% (approx. 17 g moist) are added to the following solutions:

A) 20 ml of tap water are mixed with stirring with 67.8 mg of 3-carbamoyl-2, 2, 5, 5-tetramethyl-3-pyrroline-1-oxyl, the pH with 0.5 mol / 1 H ₂ S0 ₄ solution. adjusted so that pH 4.5 results after addition of the pulp and the enzyme.

B) 5 ml of tap water are mixed with the amount of Laccase from Trame- tes versicolor that an activity of 15 U (1 U = conversion of 1 μmol ABTS / min / ml enzyme) results per g of pulp.

Solutions A and B are added together and made up to 33 ml.

After adding the pulp, mix with a dough kneader for 2 min.

Then the substance is placed in a reaction bomb preheated to 45 ° C and under 1 - 10 bar oxygen pressure for 1 -

Incubated for 4 hours.

The material is then washed over a nylon sieve (30 μm) and extracted for 1 hour at 60 ° C., 2% consistency and 8% NaOH per g of pulp.

After washing the fabric again, the kappa number is determined.

Result cf. Table 1 Example 9

Enzyme bleach with 4-phenacylidene-2, 2, 5, 5-tetramethyl-imidazolidin-1-oxyl and Softwood sulfate pulp

5 g dry cellulose (Softwood 0 ₂ delignified), consistency 30% (approx. 17 g wet) are added to the following solutions:

A) 20 ml of tap water are mixed with 67.8 mg of 4-phenacylidine-2, 2, 5, 5-tetramethyl-imidazolidine-1-oxyl with stirring, the pH value with 0.5 mol / 1 H ₂ S0 ₄ - Solution adjusted so that pH 4.5 results after addition of the pulp and the enzyme.

B) 5 ml of tap water are mixed with the amount of Laccase from Trame- tes versicolor that an activity of 15 U (1 U = conversion of 1 μmol ABTS / min / ml enzyme) results per g of pulp.

Solutions A and B are added together and made up to 33 ml.

After adding the pulp, mix with a dough kneader for 2 min.

The substance is then placed in a reaction bomb preheated to 45 ° C and incubated under 1-10 bar oxygen pressure for 1-4 hours.

The material is then washed over a nylon sieve (30 μm) and extracted for 1 hour at 60 ° C., 2% consistency and 8% NaOH per g of pulp.

After washing the fabric again, the kappa number is determined.

Result cf. Table 1 Table 1

Results Examples 1 to 9:

Enzyme dosage 15U / g pulp, incubation time 2h

Substance Mediatordosage [%]

Lignin breakdown [mg / 5g pulp]

4-hydroxy-2, 2, 6, 6-tetramethylpiperidine 63.8 16.7-1-oxy1

4-phenyl-2, 2, 5, 5-tetramethyl-3- 81.5 10.6 imidazoline-3-oxide-l-oxyl

4-oxo-2, 2, 6, 6-tetramethylpiperidine-1- 63.9 10.5 oxy ¹

4-cyano-2, 2, 6, 6-tetramethylpiperidine-1 68 19.9

-oxyl

2, 2, 6, 6-tetramethylpiperidine-l-oxyl 57.8 16.2

4-acetamido-2, 2, 6, 6-tetrametylpiperidi 79 16.7 n-l-oxyl

4-carbamoyl -2, 2, 5, 5-tetramethyl-3-imide 74 13.1 azolin-3-oxide-l-oxy

3-carbamoyl -2, 2, 5, 5-tetramethyl-3-pyrr 67.8 16.2 olin-1-oxyl

4-phenacylidene-2, 2, 5, 5-tetramethylimide 9613.8 azolidin-1-oxyl

Claims

Claims: 1) Multi-component system for changing, breaking down or bleaching lignin, lignin-containing materials or similar substances a. optionally at least one oxidation catalyst and b. at least one suitable oxidizing agent and c. at least one mediator, characterized in that the mediator is selected from the group of stable nitroxyl radicals (nitroxides). 2) Multi-component system according to claim 1, characterized in that the mediator is selected from the group of stable nitroxyl radicals (nitroxides) of the general formula (I), (II) or (III)

(I) (II) (III) in which Ar is a monovalent homo- or heteroaromatic mono- or dinuclear radical, and this aromatic radical is selected by one or more identical or different radicals R ² selected from the group consisting of halogen, formyl, cyano, carbamoyl, carboxy and ester or salt of carboxy, sulfono, ester or salt of sulfono, sulfamoyl, nitro, nitroso, amino, phenyl, aryl - -Cg-alkyl, C, -C ₁₂ alkyl -,

, C, -C ₁₀ carbonyl,

, Phospho-, phosphono-, phosphonooxy, ester or salt of the phosphonooxy may be substituted, whereby phenyl, carbamoyl and sulfamoyl residues may be unsubstituted or substituted one or more times with a residue R ³ , the amino residue being substituted once or twice with R ³ can be and the aryl-C, -C ₅ alkyl, C ^ C ^ alkyl, C, -C ₅ alkoxy, C ^ C ^ carbonyl, carbonyl-C, -C ₆ alkyl radicals can be saturated or unsaturated, branched or unbranched and can be substituted one or more times with a radical R ³ , where R ³ can be present one or more times and is the same or different and hydroxyl, formyl, cyano, carboxy radical, Ester or salt of the carboxy radical, carbamoyl, sulfono, sulfamoyl, nitro, nitroso, amino, phenyl,

.

, -Cj-Alkylcarbonylrest means and R ^{1 is} identical or different and halogen, hydroxy, mercapto, formyl, cyano, carbamoyl, carboxy, ester or salt of carboxy, sulfono, ester or salt of sulfono- residues, sulfamoyl, nitro, nitroso, amino, phenyl,

, C, -C ₁₀ carbonyl, carbonyl -C, -C ₆ alkyl -, phospho-, phosphono-, phosphono-oxy radical, ester or salt of the phosphonooxy radical and R ¹ in the case of bicyclic stable nitroxyl radicals (structure III) can also be hydrogen and carbamoyl, sulfamoyl, amino, mercapto and phenyl radicals can be unsubstituted or substituted one or more times with a radical R ⁴ and the aryl-C, -C ₃ -alkyl -,

Carbonyl-C, -C ₆ -alkyl radicals can be saturated or unsaturated, branched or unbranched and can be substituted one or more times with a radical R ⁴ , where R ^{4 is the} same or different and is hydroxyl, formyl, cyano, carboxy, ester or salt of carboxy, carbamoyl, sulfono, sulfamoyl, nitro, nitroso, amino, phenyl,

C, - C ₅ alkoxy radical, C, - C ₃ alkylcarbonyl radical means and two radicals R ³ or R ^{4 in} pairs over a bridge [-CR ⁵ R ⁶ -] _m with m equal to 0,1,2,3 or 4 can be linked and R ⁵ and R ^{6 are the} same or different and are halogen, carboxy, ester or salt of carboxy, carbamoyl, sulfamoyl, phenyl, benzoyl, C, -C ₆ alkyl ~,

, C ^ C _j -alkylcarbonyl radical and one or more non-adjacent groups [-CR ⁵ R ⁶ -] by oxygen, sulfur or an imino radical optionally substituted with -C ₃ -alkyl and two adjacent groups [-CR ⁵ R ⁶ -] can be replaced by a group [-CR ⁵ = CR ⁶ -], [-CR ⁵ = N-] or [-CR ⁵ = N (0) -]. 3) Multi-component system according to claim 1 to 2, characterized in that the mediator is selected from the group of stable nitroxy radicals (nitroxides) of the general formula (IV) and (V),

(IV) (V) where R ^{7 is the} same or different and phenyl, aryl -C, -C ₅ alkyl -,

means where phenyl radicals can be unsubstituted or substituted one or more times with a radical R ⁹ and the aryl -C, -C ₅ alkyl-, C, -C ₁₂ alkyl-,

.

can be saturated or unsaturated, branched or unbranched and can be substituted one or more times with a radical R ⁹ , where R ⁹ can be present one or more times and is the same or different and hydroxyl, formyl, carboxy, ester or salt of carboxy, carbamoyl, sulfono, sulfamoyl, Is nitro, nitroso, amino, phenyl, benzoyl, C, -C ₅ alkyl, C, - C ₆ alkoxy, C ₁ - C ₆ alkylcarbonyl and R ^{8 is the} same or different and is hydrogen, Hydroxy, mercapto, formyl, cyano, carbamoyl, carboxy, ester or salt of carboxy, sulfono, ester or salt of sulfono, sulfamoyl, nitro, nitroso, amino, phenyl,

Carbonyl

-, Phospho-, Phosphono-, Phosphonooxy residue, ester or salt of the phosphono-oxy residue means wherein carbamoyl, sulfamoyl, amino, mercapto and phenyl residues can be unsubstituted or substituted one or more times with a radical R ³ and the Aryl-C ^ C _j -alkyl-, C, -C ₁₂ -alkyl-,

.

Residues can be saturated or unsaturated, branched or unbranched and can be substituted one or more times with a residue R ³ and a [-CR ⁸ R ⁸ -] group by oxygen, one optionally with C., - C ₆ -alkyl-substituted imino radical, a (hydroxy) imino radical, a carbonyl function or a vinylidene function which may be mono- or disubstituted with R ³ , and two adjacent groups [-CR ⁸ R ⁸ -] can be replaced by a group [- CR ⁸ = CR ⁸ -] or [-CR ⁸ = N-] or [-CR ⁸ = N (0) -] can be replaced. 4) Multi-component system according to one of claims 1 to 3, characterized in that it comprises at least one oxidation catalyst. 5) Multi-component system according to claim 4, characterized in that an oxidoreductase is present as the oxidation catalyst. 6) Multi-component system according to one of claims 1 to 5, characterized in that air, oxygen, ozone, peroxides, such as H ₂ 0 ₂ or organic peroxides, peracids, such as peracetic acid, performic acid, persulfuric acid, persitric acid, metachloroperoxibenzoic acid, as the oxidizing agent, Perchloric acid, other "per-compounds", such as perborates, peracetates, persulfates or oxygen species and their radicals, such as OH ", 00H ", singlet oxygen, superoxide (0 ₂ ^~ ), ozonide, dioxygenyl cation (0 ₂ ⁺ ), dioxiranes, dioxetanes or fremy radicals can be used. 7) Multi-component system according to one of claims 1 to 6, characterized in that the mediator (component c) is selected from the group 2, 2, 6, 6-tetramethyl-piperidine-1-oxyl (TEMPO), 4-hydroxy-2 , 2, 6, 6-tetramethyl-piperidine-l-oxyl, 4-0x0-2, 2,6, 6-tetramethyl-piperidine-l-oxyl, 4-acetamido-2, 2,6, 6-tetramethyl-piperidine -l-oxyl, 4- (ethoxyfluorophosphinyloxy) -2,2,6,6-tetramethyl-piperidine-lo xyl, 4- (isothiocyanato) -2,2,6,6-tetramethyl-piperidine-l-oxyl, 4-maleimido-2,2 , 6, 6-tetramethyl-piperidine-l-oxyl, 4- (4-nitrobenzoyloxy) -2,2,6, 6-tetramethyl-piperidine-l-oxyl, 4- (phosphonooxy) -2,2,6, 6 -tetramethyl-piperidine-l-oxyl, 4-cyano-2, 2,6, 6-tetramethyl-piperidine-l-oxyl, 3-carbamoyl -2, 2,5, 5-tetramethyl-3-pyrroline-l-oxyl , 4 -phenyl -2, 2,5, 5-tetramethyl-3-imidazoline-3-oxide-l-oxyl, 4-carbamoyl -2, 2,5, 5-tetramethyl-3-imidazoline-3-oxide-l -oxyl, 4-phenacylidene-2, 2,5,5-tetramethyl-imidazolidin-l-oxyl, 3- (aminomethyl) -2, 2, 5, 5-tetramethyl-pyrrolidine-N-oxyl, 3-carbamoyl-2, 2,5, 5-tetramethyl-pyrrolidine-N-oxyl, 3-carboxy-2, 2, 5, 5-tetramethyl-pyrrolidine-N-oxyl, 3-cyano-2, 2.5, 5-tetramethyl-pyrrolidine-N-oxyl, 3-maleimido-2, 2.5, 5-tetramethyl-pyrrolidine-N- oxyl, 3- (4-nitrophenoxycarbonyl) -2,2,5,5-tetramethyl-pyrrolidin-N-ox yi- 8. Multi-component system according to one of claims 1 to 7, characterized in that the mediator 2,2,6,6 Tetramethylpiperidine-1-oxyl (TEMPO) or 4-hydroxy-2, 2, 6, 6-tetramethyl-piperidine-l-oxyl are present. 9. A method for treating lignin, lignin-containing materials or similar substances, characterized in that the components a) to c) selected in each case according to claim 1 simultaneously or in any order with a aqueous suspension of the lignin-containing material mixes. 10) Use of mediators mentioned in claim 1 as component c) for changing, breaking down or bleaching lignin, lignin-containing materials or similar substances.