EP0835225A1 - Procede enzymatique de decomposition oxydative de composes fluorescents - Google Patents

Procede enzymatique de decomposition oxydative de composes fluorescents

Info

Publication number
EP0835225A1
EP0835225A1 EP96921963A EP96921963A EP0835225A1 EP 0835225 A1 EP0835225 A1 EP 0835225A1 EP 96921963 A EP96921963 A EP 96921963A EP 96921963 A EP96921963 A EP 96921963A EP 0835225 A1 EP0835225 A1 EP 0835225A1
Authority
EP
European Patent Office
Prior art keywords
enzyme
treatment
fluorescent compounds
paper
peroxidases
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP96921963A
Other languages
German (de)
English (en)
Inventor
Philippe Schyns
Jürgen REINERS
Joachim König
Ulrich Feldhues
Rainhard Koch
Eckhard Wenderoth
Udo Eckstein
Uwe Vogt
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bayer AG
Original Assignee
Bayer AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Bayer AG filed Critical Bayer AG
Publication of EP0835225A1 publication Critical patent/EP0835225A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/34—Biological treatment of water, waste water, or sewage characterised by the microorganisms used
    • C02F3/342—Biological treatment of water, waste water, or sewage characterised by the microorganisms used characterised by the enzymes used
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/72—Treatment of water, waste water, or sewage by oxidation
    • C02F1/722—Oxidation by peroxides

Definitions

  • the invention relates to a method for the enzymatic degradation of fluorescent compounds which are located in aqueous systems, in which such aqueous systems with one or more oxidases or peroxidases and O 2 , H, O 2 or compounds which contain O 2 or Form H 2 O 2 are treated.
  • Fluorescent compounds are mainly used as optical brighteners. These are substances that in solution or on a substrate UV light, e.g. absorb the proportion of daylight at approximately 280 to 430 nm and emit the absorbed energy as blue fluorescent light of the wavelength of approximately 400 to 500 nm. Textiles, paper, cardboard or cardboard appear whiter and lighter after treatment with optical brighteners because part of the area of the daylight spectrum that is not perceptible to the eye is visible
  • Brighteners absorb in the UV range or reduce the reflection in this range. At the visible wavelengths, usually with a maximum at 430 to 450 nm, they increase the reflection due to the emitted fluorescence. Brighteners are the more effective the whiter the substrate is. However, they are not a substitute for bleach. The industrially important ones
  • Brighteners are compounds which are derived from 4,4'-diaminostilbene-disulfonic acid, distyryl-benzene, distyryl-biphenyl, stilbenyl-2H-triazole, certain benzoxazoles, benzofurans and coumarins.
  • Optical brighteners are used in a variety of ways. As is well known, detergents brighteners are known to be added in order to replace the brightener components present in textiles which, owing to the poor fixation to the fibers, can be eluted when washing *. When such washing processes are carried out industrially, discontinuous or continuous processes analogous to the known dyeing processes are used.
  • Brighteners are also used in the production of uncoated and coated papers, in particular printing papers.
  • the degree of whiteness can be increased considerably by using very small amounts; Brighteners work with the greatest efficiency in the concentration range of 0.002 to 2.0% by weight, based on the substrate, and should be distributed as monomolecularly as possible on the substrate.
  • Brighteners can be added directly to the pulp suspension from which the paper is formed by dewatering.
  • the most common application in practice is the use in the paper surface, the brightener being applied to the paper surface together with other auxiliaries, such as surface sizing agents or starch, for example using a size press.
  • Another important area of application is the addition of brighteners to coating colors.
  • inexpensive triazinyl-aminostilbenes or di-styryl-biphenyls are preferably used.
  • optical brighteners for example in liquid or powder formulations.
  • anionic brighteners especially those with sulfonic acid groups, have been developed so that they behave in relation to a cellulose noun and are fixed against bleeding.
  • the object of the invention is therefore to provide a method which degrades fluorescent compounds in such a way that subsequent biological wastewater treatment action is possible.
  • the method according to the invention should also be applicable to TCF pulps in which only an oxidative removal of fluorescent compounds, for example by chlorine or hypochlorite, has hitherto existed.
  • the disadvantages of the known methods with their high use of chemicals and the formation of chlorine-containing compounds are to be overcome; In the case of persulfate degradation, for example, high pH values have to be set, which in turn leads to a high salt load after the necessary neutralization.
  • the use of the chemicals mentioned is cost-intensive. Such processes are therefore in need of economic improvement.
  • oxidases and peroxidases are suitable for degrading fluorescent components, for example optical brighteners in waste water and circuits, which contain such fluorescent compounds, using O- or H 2 O 2 .
  • peroxidases can be used for the oxidation of phenolic bodies.
  • peroxidases for bleaching wood pulp, for treating wastewater from the pulp industry or for use in textile washing are proposed, in the latter case in particular to prevent back training.
  • EP 406 617 proposes ligninases in combination with xylanases for the bleaching of paper pulp. Enzymes for the degradation of lignin are claimed in EP 429 422. According to US Pat. No. 5,370,770, soybean peroxidase is used for deinking waste paper. The degradation of phenolic impurities with the aid of peroxidases is also proposed in US Pat. No. 5,178,762.
  • the invention relates to a method for the oxidative degradation of in aqueous
  • Fluorescent compounds present in systems which is characterized in that such aqueous systems with at least one enzyme from the group of oxidases and peroxidases, which are both present as such and can also be associated with at least one further enzyme with hydrolytic activity, and with an oxidizing agent from the group of mixtures containing or forming O 2 , H, O 2 and O 2 or H 2 O 2 at a temperature of 5 to 90 ° C and a pH of 4 to 10 treated.
  • Treatment can be in the absence or in the presence of surfactants
  • Aqueous systems in the sense of the invention are waste water from the production or treatment of textiles, fiber structures, such as paper, cardboard or cardboard, the fibers and polymers on which they are based, in particular those based on cellulose, and also aqueous dispersions or suspensions of such textile fiber structures, fibers and polymers.
  • the aqueous system according to the invention can also be a treatment liquor, for example a textile treatment liquor, preferably one for clothing textiles.
  • Fiber structures, such as paper, cardboard or cardboard, in particular lightened, coated or uncoated printing and writing papers are usually opened in a pulper when they are recycled, freed of coarse impurities and then subjected to washing or flotation deinking.
  • the enzymatic treatment according to the invention for the degradation of optical brighteners can take place before, during or after the detachment of the printing ink components. The pulp cleaned in this way can then be subjected to a further bleaching step, likewise
  • Enzymes can be used. In the event that the optical brightener is absorbed on the fiber, but is to be used in the course of recycling for the production of unlightened paper, cardboard or cardboard, it may be advantageous to use further enzymes in addition to the oxidases or peroxidases, for example the desorption of the optical brightener from the fiber.
  • the method according to the invention for oxidative degradation with the aid of enzymes from the groups of oxidases and peroxidases is in principle accessible to all fluorescent compounds, in particular those which are used as optical brighteners.
  • a large part of such fluorescent compounds contains, as already mentioned above, the 4,4'-diaminostilbene disulfonic acid, the distyryl-benzene, the distyryl-biphenyl, the stilbenyl-2H-triazole, the benzoxazole, the benzofuran or the coumarin as the molecular framework .
  • those are particularly important which contain the 4,4'-diaminostilbene disulfonic acid or the distyryl biphenyl as the molecular backbone.
  • fluorescent compounds which contain the 4,4'-diaminostilbene-disulfonic acid skeleton can preferably be subjected to the method according to the invention.
  • Important examples of fluorescent compounds are, for example, those of the formula
  • X amino, methylamino, ethylamino, dimethylamino, diethylamino, 2-hydroxyethyl amino, 3-hydroxypropylamino, di- (2-hydroxyethyl) amino, di- (2-hydroxypropyl) amino, 2 -Sulfo-ethylamino, morpholino, anilino, chloranilino, sulfoanilino, methylanilino or disulfoanilino and
  • X 2 is hydroxy, methoxy, ethoxy, methoxyethoxy, chlorine or X,
  • X 3 and X 4 denote hydrogen, methyl, ethyl, phenyl or sulfophenyl
  • X 5 is hydrogen, methyl, ethyl, methoxy, ethoxy, chlorine or sulfo, in all cases
  • Z is hydrogen, an alkali metal, amine or ammonium ion.
  • Such fluorescent compounds are known, for example, from EP 409 028. Important individual examples of this are those of the following formulas (A) to (G), some of which are products from Bayer AG under the trade name Blankophor:
  • Enzymes from the group of oxidases and peroxidases are suitable for use in the method according to the invention, which according to "Enzyme Nomenclature 1984, Academic Press Inc., New York, London "(EC) belong to the larger group of oxidoreductases that catalyze the electron transfer between different substances.
  • EC oxidoreductases
  • Peroxidases are enzymes which catalyze the oxidation of a substrate with hydrogen peroxide and which are obtainable from plant, microbial or animal sources. Examples include: horseradish peroxidase, soybean peroxidase or a peroxidase from Coprinus. for example Coprinus cinereus or Coprinus macrorhizus. or Bacillus. for example
  • Phanerochaete chrysosporium Cellobiose oxidase from Phanerochaete chrysosporium or Humicola. Glucose oxidase, catechol oxidase, polyphenol oxidase.
  • the oxidases also include laccases (E.C. 1.10.3.2), in particular laccases from Trametes versicolor. Phanerochaete chrysosporium; such enzymes are for example from
  • Polyporus pinsitus (Trametes villosa) produces.
  • the peroxidases are used together with H 2 0 2 or a compound containing or forming H 2 O 2 as the oxidizing agent.
  • H 2 O itself, usually in the form of differently highly concentrated and commercially available aqueous H 2 O, solutions, the following should therefore be mentioned: perborates, persulfates, percarbonates,
  • Peresters peroxides, Fenton's reagent, peracids or enzymatic systems which form H 2 0 2 , such as glucose / glucose oxidase / oxygen, amino acid oxidase, urea oxidase, cholesterol oxidase, amine oxidase or alcohol oxidase.
  • Oxidases including laccases, are used with 0 2 or O 2 containing or forming compounds or 0 -, - sources.
  • auxiliaries for example alkali metal halides, sulfates, phosphates, acetates etc.
  • saccharides for example Cellobiose, glucose, fructose, ribose, mannose, galactose, arabinose, trehalose, xanthans
  • halide ions for example Cellobiose, glucose, fructose, ribose, mannose, galactose, arabinose, trehalose, xanthans
  • buffer solutions e.g. phosphate, borate, acetate buffer
  • reducing or oxidizing agents e.g. NaHSO 3 , Na 2 S 2 O 4 or formamidine - sulfinic acid or perborate, periodate or percarbonate.
  • accelerators for the action of the peroxidases or oxidases.
  • the effect of such accelerators is attributed to the fact that short-lived radicals or other oxidized states are formed in the reaction system, which can contribute to the oxidative degradation of the fluorescent compounds.
  • Metal ions, halide ions, phenol, p-hydroxybenzoic acid, p-hydroxybenzenesulfonate, p-hydroxycinnamic acid, 7-hydroxycoumarin, guaiacol or vanillin can also be used as accelerators.
  • the accelerator can e.g. in an aqueous system with the enzyme in a concentration of 0.01 to 100 ⁇ M, preferably 0.1 to 50 ⁇ M, particularly preferably 1 to 10 ⁇ M.
  • the enzymes mentioned from the group of oxidases and peroxidases can either be present as such alone or be associated with at least one further enzyme with hydrolytic activity.
  • the latter case has the advantage that the enzyme preparations obtained from the sources mentioned above (plants, microorganisms or fungi), which are often a mixture of several enzymes, do not have to be separated into individual enzymes. This avoids additional costs.
  • Such further enzymes with which oxidases and peroxidases can be associated are, for example, hydrolases, such as cellulases, for example from Phanerochaete. Humicola. Fusarium. Pseudomonas.
  • Trichoderma reesei or Aspergillus hemicellulases, preferably xylanases, such as Pulpzyme HC ® ; Lipases, for example from Pseudomonas. Humicola. Candida, Chromobacter. Aspergillus: (. Fa products of Novo Nordisk) proteases, such as MPX NUE 0.6, Aquaderm ®, Pyrase ®, Alcalase ®, Esperase ®; Amylases as Denimax ®, Termamyl ® and others; Pectinases, dehalogenases and pullulanases.
  • xylanases such as Pulpzyme HC ®
  • Lipases for example from Pseudomonas. Humicola. Candida, Chromobacter. Aspergillus: (. Fa products of Novo Nordisk) proteases, such as MPX NUE 0.6, Aquaderm ®, Pyrase ®, Alcalase ®,
  • Such further enzymes are mentioned, for example, in WO 91/17243, WO 91/17244, WO 91/10732, US 5,338,403, WO 94/23053 and WO 91/14019. It can furthermore be advantageous to mobilize fluorescent compounds, for example brighteners, which are adsorbed on the fiber, by also using surface-active aids.
  • Anionic, cationic or nonionic and amphoteric surfactants are suitable as such surface-active compounds.
  • salts of fatty acids ammonium salts of fatty amines, polyethers with long-chain alkyl radicals, the polyethers being formed by ethoxylation and / or propoxylation, partial fatty acid esters of glycerol, trimethylolpropane, pentaerythritol, oleic acid sarcosides, sulfosuccinates, polyacrylic acid derivatives with hydrophobic side chains or End groups, polyamide amine emulsifiers, etc.
  • surfactants are examples of surfactants.
  • the method according to the invention is carried out at a temperature of 5 to 90 ° C., preferably 10 to 60 ° C., particularly preferably 20 to 55 ° C. and in the pH range of 4 to 10, preferably 5 to 8.
  • the residence time of the aqueous system to be treated in the context of the method according to the invention depends on many factors, for example on the concentration of the fluorescent compound, the concentration of the enzyme, the concentration of the oxidizing agent, the temperature and the pH. In many cases, a time period of at most 200 minutes, in many cases of at most 60 minutes and in some cases of at most 10 minutes, will be required in order to recognize from the samples that the fluorescence has largely been quenched or has been quenched to an extent that is striven for in individual cases.
  • the quenching of the fluorescence on the basis of a sample taken here indicates that the fluorescent compound to be oxidized has been oxidatively split into at least two fragments. This can be proven by chromatographic methods such as TLC or HPLC.
  • a solution of an oxidase or peroxidase and one of the oxidizing agents mentioned are added to the aqueous system.
  • the concentration of the fluorescent compound can be in the range from 3 parts per billion (ppb) up to 1% by weight or more if, for example, it is a concentrated medium with a strongly fluorescent compound.
  • the amounts of enzyme used depend on the content of fluorescent compound in the aqueous system.
  • the oxidase is used in an amount of 1 to 10 7 laccase units per 1 g of the fluorescent compound.
  • ABTS 2,2'-azino-bis- (3-ethyl-benzothiazoline-6-sulfonic acid)
  • the enzyme dosage required to disappear the fluorescence is, for example, 100 to 10 8 units per kg of dry paper, preferably 100 to 10 6 units per kg of dry paper, particularly preferably 100 to 10 ⁇ units / kg of dry paper.
  • Enzyme activity can be compensated for by making corrections in the dosage.
  • the H 2 O 2 concentration in the aqueous system to be treated is generally 0.001 mmol to 2.0 mol, preferably 0.01 mmol to 1 mol, per liter. Based on the dry substance that is present in the aqueous system to be treated, preferably 0.001 to 5% by weight of H 2 O 2 is sufficient. If one wishes to focus on the amount of fluorescent compound, the R, O -, - amount is preferably 1 x 10 "5 to 1 x IO " 2 % by weight, based on the fluorescent compound. If O 2 is used as the oxidizing agent, pure oxygen can be used, but atmospheric air or oxygen-enriched atmospheric air can also be used; Since the O 2 concentration of the atmospheric air is normally sufficient in laccase systems, this option is also used.
  • reaction time can be shifted to shorter values by correspondingly increasing the amount of enzyme.
  • the aqueous system to be treated is a suspension or slurry which accordingly has a solids content
  • this solids content is 0.1 to 30% by weight, preferably 0.5 to 10% by weight, of the total suspension or slurry.
  • the course and completeness of the oxidative degradation of the fluorescent compound can be followed by measuring the fluorescence.
  • a sample of the aqueous system can be introduced directly into a measuring device; however, chromatographic methods can also be used to separate the substances present in the aqueous system.
  • the enzyme can be deactivated by simply changing the pH and / or increasing the temperature. In closed circuits, this is generally not necessary, so that further enzyme need only be added if the enzyme activity decreases. An addition of catalases can also serve to interrupt the enzyme activity.
  • a carrier material with enzymes in immobilized form being arranged, for example, in a column and brought into contact with the aqueous system to be treated;
  • a carrier material with enzymes in immobilized form being arranged, for example, in a column and brought into contact with the aqueous system to be treated;
  • the method according to the invention generally requires a significantly lower use of oxidizing agents and auxiliaries and enables faster and more environmentally friendly disposal of fluorescent compounds.
  • the chemical requirement for a non-enzyme-catalyzed degradation with potassium perox odi sulfate at pH 10.5 and 60 ° C, a consistency of 5% by weight of a dispersion and a treatment time of 180 minutes 1 to 2% by weight of persulfate, based on the solid (for example cellulose).
  • cationic polymeric auxiliaries up to 2% by weight of the auxiliary is used in order to achieve quantitative quenching when 0.8% by weight of fluorescent compound is used. Dismantling does not take place here, or only to a minor extent.
  • the fragments obtained by the enzymatic degradation of the fluorescent compounds are generally more accessible to microbiological degradation in a wastewater treatment plant than the untreated fluorescent compounds.
  • a stock solution with a concentration of 0.05% (a 25% solution) of a brightener of the formula (A) was in a 50 mM potassium phosphate buffer ( pH 7).
  • the sample was incubated with 500 units of a horseradish peroxidase (Fluka, No. 77333) at 28 ° C.
  • the enzyme had an activity of 700 units / mg. 1 unit oxidizes 1 ⁇ mol ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) per minute at 25 ° C and pH 6.
  • the concentration of the peroxidase was 100 units / ⁇ l brightener (calculated for 25% delivery form).
  • the hydrogen peroxide concentration was 0.15 mmol / 1.
  • the absorption spectrum was recorded with a spectrophotometer in the wavelength range between 200 and 500 nm. Measurement of emission at
  • 440 nm was carried out using a fluorescence spectrophotometer at an excitation wavelength of 280 or 350 nm.
  • the intensity of the absorption band at 350 nm decreased by 72%.
  • the enzyme treatment only a small emission was observed at 440 nm, which occurs in an intact brightener molecule by excitation with a wavelength of 280 or 350 nm.
  • the fluorescence was weakened by 90 to 95%.
  • a stock solution with a concentration of 0.05% (a 25% solution, v / v) of a brightener of the formula (A) was prepared in a 50 mM potassium phosphate buffer (pH 7).
  • the sample was incubated with 10 units of a peroxidase (Novozym 502, Novo Nordisk) at 37 ° C.
  • the enzyme is a recombinant heme-containing enzyme that was originally isolated from Basidiomycetes and has an activity of 10,000 PODU / g.
  • the enzyme also has a side activity as an amylase.
  • the concentration of the peroxidase was 7 units / ⁇ l brightener (calculated for
  • the enzyme treatment led to a reduction of the absorption at 350 nm by approx. 90%.
  • Example 1 was repeated with the change that peroxidase from Example 2 was used in a concentration of 700 units per ⁇ l of brightener. After a few seconds the brightener was completely fragmented.
  • 100 g base paper consisting of 70% bleached pine sulfate and 30% bleached birch sulfate pulp, which contained 0.25% active substance according to formula (A) above and had a CIE whiteness of 125, was obtained at a consistency of 5% opened (2000 ml, 3000 rpm).
  • Example 6 comparative example
  • the brightener quenching can also be achieved by treating a 0.5% solution of brightener of the formula (A) at pH 10.5 / 60 ° C. with 2% potassium peroxodisulfate for 120 minutes.
  • the conditions for the breakdown of the brightener are much more drastic (pH, temperature) and require a higher one
  • Amount of oxidizing agent used with a longer dwell time is a greater amount of oxidizing agent used with a longer dwell time.

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Microbiology (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Biodiversity & Conservation Biology (AREA)
  • Detergent Compositions (AREA)
  • Paper (AREA)

Abstract

Des composés fluorescents contenus dans des systèmes aqueux peuvent être décomposés par traitement desdits systèmes aqueux avec une enzyme du groupe des oxydases et des peroxydases et un agent d'oxydation du groupe des composés formant O2, H2O2 et O2 ou les contenant, à une température comprise entre 5 et 90 °C et à un pH compris entre 5 et 10. Le traitement peut s'effectuer en présence d'adjuvants tensioactifs.
EP96921963A 1995-06-23 1996-06-10 Procede enzymatique de decomposition oxydative de composes fluorescents Withdrawn EP0835225A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE1995123389 DE19523389A1 (de) 1995-06-23 1995-06-23 Enzymatische Methode zum oxidativen Abbau von fluoreszierenden Verbindungen
DE19523389 1995-06-23
PCT/EP1996/002512 WO1997000834A1 (fr) 1995-06-23 1996-06-10 Procede enzymatique de decomposition oxydative de composes fluorescents

Publications (1)

Publication Number Publication Date
EP0835225A1 true EP0835225A1 (fr) 1998-04-15

Family

ID=7765393

Family Applications (1)

Application Number Title Priority Date Filing Date
EP96921963A Withdrawn EP0835225A1 (fr) 1995-06-23 1996-06-10 Procede enzymatique de decomposition oxydative de composes fluorescents

Country Status (3)

Country Link
EP (1) EP0835225A1 (fr)
DE (1) DE19523389A1 (fr)
WO (1) WO1997000834A1 (fr)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6294047B1 (en) 1999-07-30 2001-09-25 Institute Of Paper Methods for reducing fluorescence in paper-containing samples
US7319112B2 (en) 2000-07-14 2008-01-15 The Procter & Gamble Co. Non-halogenated antibacterial agents and processes for making same
EP1497264A2 (fr) 2002-04-11 2005-01-19 Instytut Farmaceutyczny Preparation d analogues alkyl-24 de cholecalciferol et de composes non racemiques
DE102010035003B4 (de) * 2010-08-20 2015-08-06 PicoQuant GmbH. Unternehmen für optoelektronische Forschung und Entwicklung Räumlich und zeitlich hochauflösende Mikroskopie
CN109851027A (zh) * 2019-01-28 2019-06-07 东莞理工学院 一种阿奇霉素废水的处理方法

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4485016A (en) * 1983-05-13 1984-11-27 Phillips Petroleum Company Enzymatic removal of aromatic hydroxy compounds and aromatic amines from waste waters
CA1228431A (fr) * 1983-05-13 1987-10-20 Thomas R. Hopkins Elimination au moyen d'enzymes de composes hydroxy aromatiques et d'amines aromatiques dans les eaux usees
IT1251640B (it) * 1991-10-28 1995-05-17 Ausimont Spa Processo per ossidare composti aromatici ed alifatici
AU4104493A (en) * 1992-04-16 1993-11-18 Promega Corporation Method and device for bioremediation
DK144392D0 (da) * 1992-12-01 1992-12-01 Novo Nordisk As Aktivering af enzymer

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9700834A1 *

Also Published As

Publication number Publication date
DE19523389A1 (de) 1997-01-09
WO1997000834A1 (fr) 1997-01-09

Similar Documents

Publication Publication Date Title
DE69912128T2 (de) Verfahren zur herstellung lignocellulosehaltiger pulpe aus nicht holzartigem material
Bajpai et al. Biodeinking
US6241849B1 (en) Methods for deinking and decolorizing printed paper
Virk et al. Use of laccase in pulp and paper industry
EP0943032B1 (fr) Systeme a composants multiples pour modifier, decomposer ou blanchir la lignine ou des materiaux qui contiennent de la lignine, et son procede d'utilisation
Archibald Lignin peroxidase activity is not important in biological bleaching and delignification of unbleached kraft pulp by Trametes versicolor
AU663501B2 (en) Process, using enhanced-action laccase enzymes, for the delignification or bleaching of lignocellulose-containing material or for the treatment of waste water
EP0825294B2 (fr) Système à plusieurs constituants pour modifier, dégrader ou blanchir la lignine, ou les matières contenant de la lignine ainsi que procédés l'utilisant
DE69520589T2 (de) Verwendung einer einkomponentencellulose zur entfernung von tinten, streichmasse und toner aus druckpapier
DE69506465T2 (de) Verfahren zur Verminderung der Fluoreszenz in entfärbtem Zellstoff
DE69710046T2 (de) Verfahren zur erhöhung der negativen ladung eines lignocellulosematerials und ein modifiziertes lignocellulosematerial mit erhöhter ladungsdichte
EP0835225A1 (fr) Procede enzymatique de decomposition oxydative de composes fluorescents
CN101171386B (zh) 二氧化氯处理组合物和方法
DE69015294T2 (de) Bleichen von Holzstoff mit Enzymen.
EP2475726B1 (fr) Procédé de désencrage de suspensions contenant une encre pour jet d'encre
DE19909546C1 (de) Mehrkomponentensystem zur enzymkatalysierten Oxidation von Substraten sowie Verfahren zur enzymkatalysierten Oxidation
Pathak et al. Fungal enzymes application for recycling of waste papers
Sudha et al. Bleaching of bagasse pulp with enzyme pre-treatment
Bajpai et al. Biodeinking
Bajpai et al. Enzymatic deinking
Nkwonji How to minimize the impact of bleaching pulp in pulp mill on water quality on river Hindon, India
EP1031657A1 (fr) Procede de blanchiment de fibres secondaires
Kumar et al. Chinnadurai Muralidharan 11 Role of microbial oxidative enzymes
Chandra Improving the brightness and bleachability of douglas-fir mechanical pulps using white-rot fungi and laccase enzymes
JPH07279074A (ja) 上質古紙パルプの製造方法及び前記パルプを原料とする紙

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19980123

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE ES FR GB IT LI NL

17Q First examination report despatched

Effective date: 19981019

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20021119