EP0208625A1 - Treatment of chemical pulps with hydrogen peroxide in order to bleach them - Google Patents
Treatment of chemical pulps with hydrogen peroxide in order to bleach them Download PDFInfo
- Publication number
- EP0208625A1 EP0208625A1 EP86420138A EP86420138A EP0208625A1 EP 0208625 A1 EP0208625 A1 EP 0208625A1 EP 86420138 A EP86420138 A EP 86420138A EP 86420138 A EP86420138 A EP 86420138A EP 0208625 A1 EP0208625 A1 EP 0208625A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- hydrogen peroxide
- weight
- treatment according
- pulp
- sodium
- 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.)
- Granted
Links
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/16—Bleaching ; Apparatus therefor with per compounds
- D21C9/163—Bleaching ; Apparatus therefor with per compounds with peroxides
Definitions
- the present invention relates to the treatment of chemical paper pulps with hydrogen peroxide with a view to their bleaching.
- the lignin level of the pulp translated by the profession into a KAPPA index, practically determines the overall quantity of chemical bleaching agent to be used.
- the treatment according to the present invention does not involve the drawbacks of known methods and provides pulps whose KAPPA index can go as far as being less than 10 from chemical pulp of softwoods with a very high efficiency of the agent. chemical used, hydrogen peroxide.
- the chemical softwood pulp bowls is subjected to the action of hydrogen peroxide at a temperature between 90 ° C and 100 ° C in two stages, the first EFFEC - killed at a pH between 8.5 and 9.5, in the presence of at least one metal ion sequestering agent chosen from nitrogen sequestrants and sequestrants derived from polyphosphoric and polyphosphonic acids, in an amount equal to at least 3 g / 1 of bath, so to consume an amount by weight of hydrogen peroxide of between 0.3% and 2.5% of the weight of the dry paste, the second carried out at a pH at least equal to 11, in the presence of at least 3.10 -3 gram atoms of magnesium in the form of magnesium hydroxide Mg (OH) 2 per cent grams of dry paste to consume hydrogen peroxide during this second stage so that the total weight consumption of hydrogen peroxide during the two stages is between 2% and 5% of the weight of the dry dough.
- the first EFFEC - killed at a pH between 8.5 and 9.5
- the nature of the chemical agent capable of reaching the pH values defined for the first step is not critical, the basifying chemical agent chosen, however, having to be neither oxidized nor reduced by hydrogen peroxide.
- Sodium hydroxide and sodium carbonate meet the above definition, as also, and preferably, sodium tripolyphosphate, the sodium salt of ethylenediaminetetraacetic acid and the sodium salt of diethylenetriaminepentaacetic acid.
- the pH keeps during this first stage a value as constant as possible which is achievable by known techniques, for example the use of buffers or the continuous or intermittent introduction of one or more chemical agents such as defined above.
- sodium tripolyphosphate the sodium salt of ethylenediaminetetracetic acid and the sodium salt of diethylenetriaminepentaacetic acid are preferably used.
- the duration of the first stage is generally less than 4 hours.
- sodium hydroxide and sodium carbonate are particularly suitable.
- magnesium hydroxide can be introduced as it is or formed in the treatment bath from a magnesium salt such as chloride, nitrate or sulfate, the anion of which is inert towards with respect to hydrogen peroxide.
- a magnesium salt such as chloride, nitrate or sulfate, the anion of which is inert towards with respect to hydrogen peroxide.
- the duration of the second stage is generally between 2 and 5 hours.
- Consistency is not a critical factor for carrying out the two stages of treatment according to the invention. For practical and economic reasons it is always preferable that the consistency is between 3% and 25% and better between 5% and 15%.
- the amount of hydrogen peroxide used is of course at least equal to the quantity to be consumed and is generally at most equal to 5% by weight of the weight of dry pulp, preferably 3 , About 5%.
- the paste can be separated in the usual way from the liquor of the bath and subjected in a known manner to an alkaline extraction before the second stage of the treatment.
- This alkaline extraction generally carried out at a temperature of the order of 90 ° C to 120 ° C, is preferably carried out in the majority of cases. However, it remains optional and may even advantageously not be carried out in particular when the conditions chosen to perform the first step are such that the hydrogen peroxide used in it is consumed almost entirely.
- the liquors of the baths of the two stages are separated from the dough, they can respectively be advantageously used to contribute to the constitution of each of these baths in their initial composition.
- the pulp treated according to the invention can be bleached according to usual methods, the economy and efficiency of which are improved.
- the conditions defined for carrying out the first step are those which make it possible to obtain, after the second step, chemical pulps with a KAPPA index most generally less than 15 when the chemical pulp to be treated is chemical pulp of softwoods, and a particularly advantageous overall saving in treatment which is reflected, for example, in the high efficiency of hydrogen peroxide.
- H 2 0 2 consumed being the overall quantity of hydrogen peroxide consumed in% by weight of the weight of dry pulp
- KAPPA the difference between the value of the KAPPA index of the untreated pulp and the value of the index KAPPA of the pulp treated according to the invention.
- the conditions are such that, as defined above, the pH in the first step is between 8.5 and 9.5, the pH in the second step as elsewhere in the comparative example is at least equal to 11.
- a chemical pulp of resinous wood with a KAPPA index equal to 28.5 is treated for 2 hours at 90 ° C. at the consistency of 5% in the presence of 3.4% of hydrogen peroxide H 2 0 2 and of 41, 4% sodium tripolyphosphate TPP.
- the dough After alkaline extraction carried out for 1 hour at 90 ° C in the presence of 20% sodium hydroxide NaOH, the dough, with a consistency of 5%, is subjected to 90 ° C and for 2 hours, to the action of 2 , 7% H 2 0 2 in the presence of 3.2% NaOH and 0.5% magnesium hydroxide Mg (OH) 2 .
- Example 2 The same paste as in Example 1 is subjected, at 90 ° C. and for 2 hours, to the action of 3.4% of N 2 O 2 in the presence of 4% of NaOH and 0.6% of Mg ( OH) 3 , the consistency being 5%.
- a chemical pulp of resinous wood with a KAPPA index equal to 33 is treated at the consistency of 5%, at 90 ° and for 1 hour in the presence of 0.6% of H 2 0 2 and 17.2% of TPP.
- the paste is subjected in a second step to the action of 2.7% of H 2 O 2 in the presence of 4% of NaOH and of 0.25% of Mg (OH) 2 , at 90 ° C for 5 hours.
- the KAPPA index of the treated pulp is 3 times lower than before treatment and Ef. is around 7.
- the KAPPA index of the treated pulp is 10.5 with an overall consumption of H 2 0 2 of 2 .0%. Ef. is then close to 9.0.
- the consumption of H 2 0 2 in the first stage is 0.3% and it is total in the second stage.
- the paste After treatment, the paste has a KAPPA index of 15 and Ef. is equal to 5.
- Example 4 is repeated, but the pH in the first step is reached by means of ethytenediaminetetracetic acid and sodium hydroxide and is maintained at 9.5 by addition of NaOH.
- Example 4 The results of Example 4 are practically found.
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Paper (AREA)
- Ultra Sonic Daignosis Equipment (AREA)
- Stereophonic System (AREA)
- Measuring Leads Or Probes (AREA)
- Treatment Of Fiber Materials (AREA)
- Polysaccharides And Polysaccharide Derivatives (AREA)
Abstract
Description
La présente invention concerne le traitement de pâtes papetières chimiques par le peroxyde d'hydrogène en vue de leur blanchiment.The present invention relates to the treatment of chemical paper pulps with hydrogen peroxide with a view to their bleaching.
Les pâtes papetières chimiques ou pâtes cellulosiques écrues obtenues par cuisson des matières cellulosiques selon les procédés dits au sulfite, au sulfate ou procédé Kraft, à la soude ou au carbonate, demandent a être blanchies pour que les produits en dérivant aient les qualités qu'exige leur destination.Unbleached chemical pulp or cellulosic pulp obtained by cooking cellulosic materials according to the so-called sulphite, sulphate or Kraft process, with soda or carbonate, needs to be bleached so that the products derived from it have the qualities required their destination.
Le taux de lignine de la pâte, traduit par la profession en indice KAPPA, détermine pratiquement la quantité globale d'agent de blanchiment chimique à mettre en oeuvre.The lignin level of the pulp, translated by the profession into a KAPPA index, practically determines the overall quantity of chemical bleaching agent to be used.
Le blanchiment pourra être assuré d'une façon d'autant plus efficace et économique dans un nombre limité d'étapes que l'indice KAPPA initial sera plus faible.Money laundering can be carried out all the more efficiently and economically in a limited number of stages the lower the initial KAPPA index.
Les procédés de cuisson cités plus haut ne permettent malheureusement pas d'atteindre directement un indice KAPPA de faible valeur sans dégradation prononcée des propriétés mécaniques des fibres cellulosiques.The cooking processes mentioned above unfortunately do not allow a low KAPPA index to be reached directly without pronounced degradation of the mechanical properties of the cellulose fibers.
L'application du chlore et de ses dérivés à caractère oxydant ne permet pas non plus, directement à partir de pâtes chimiques de bois résineux, d'abaisser l'indice KAPPA de celles-ci à des valeurs avoisinant 10 sans que se forment des effluents fortement colorés, polluants et corrosifs.The application of chlorine and its oxidative derivatives also does not make it possible, directly from chemical pulp of resinous wood, to lower the KAPPA index thereof to values around 10 without the formation of effluents strongly colored, polluting and corrosive.
Dans le cas encore de bois résineux le peroxyde d'hydrogène, agent oxydant non chloré dont la mise en oeuvre est la plus aisée, appliqué en milieu alcalin directement sur les pâtes chimiques, ne conduit qu'à des indices KAPPA compris entre 20 et 25 environ.In the case of resinous wood as well, hydrogen peroxide, a non-chlorinated oxidizing agent whose implementation is the easiest, applied in an alkaline medium directly on chemical pulps, only leads to KAPPA indices of between 20 and 25 about.
Un prétraitement en milieu acide tel que décrit par exemple dans la demande de brevet japonais n° 76.102 103 ou la demande de brevet français publiée sous le numéro 2 520 397 ramène cette valeur à 15-20 mais soulève les difficultés déjà signalées dues aux effluents par suite de l'alternance d'étapes en bain acide et en bain alcalin qu'implique la technique proposée.Pretreatment in an acid medium as described for example in Japanese patent application No. 76,102,103 or the French patent application published under the number 2,520,397 reduces this value to 15-20 but raises the difficulties already reported due to effluents by following the alternation of steps in acid bath and in alkaline bath implied by the proposed technique.
Le traitement selon la présente invention n'implique pas les inconvénients des procédés connus et procure des pâtes dont l'indice KAPPA peut aller jusqu'à être inférieur à 10 à partir de pâtes chimiques de bois résineux avec une efficacité très élevée de l'agent chimique mis en oeuvre, le peroxyde d'hydrogène.The treatment according to the present invention does not involve the drawbacks of known methods and provides pulps whose KAPPA index can go as far as being less than 10 from chemical pulp of softwoods with a very high efficiency of the agent. chemical used, hydrogen peroxide.
Il est caractérisé en ce que la pâte chimique de bols résineux est soumise à l'action du peroxyde d'hydrogène à une température comprise entre 90°C et 100°C, en deux étapes, la première effec- tuée à un pH compris entre 8,5 et 9,5,en présence d'au moins un agent sequestrant des ions métalliques choisi parmi les sequestrants azotés et les sequestrants dérivés des acides polyphosphoriques et polyphosphoniques, en quantité égale au moins à 3 g/1 de bain, de façon à consommer une quantité en poids de peroxyde d'hydrogène comprise entre 0,3 % et 2,5 % du poids de la pâte sèche, la seconde effectuée à un pH au moins égal à 11, en présence d'au moins 3.10-3 atomes-gramme de magnésium sous forme d'hydroxyde de magnésium Mg (OH)2 pour cent grammes de pâte sèche pour consommer du peroxyde d'hydrogène au cours de cette seconde étape de façon à ce que la consommation pondérale totale de peroxyde d'hydrogène au cours des deux étapes soit comprise entre 2 % et 5 % du poids de la pâte sèche.It is characterized in that the chemical softwood pulp bowls is subjected to the action of hydrogen peroxide at a temperature between 90 ° C and 100 ° C in two stages, the first EFFEC - killed at a pH between 8.5 and 9.5, in the presence of at least one metal ion sequestering agent chosen from nitrogen sequestrants and sequestrants derived from polyphosphoric and polyphosphonic acids, in an amount equal to at least 3 g / 1 of bath, so to consume an amount by weight of hydrogen peroxide of between 0.3% and 2.5% of the weight of the dry paste, the second carried out at a pH at least equal to 11, in the presence of at least 3.10 -3 gram atoms of magnesium in the form of magnesium hydroxide Mg (OH) 2 per cent grams of dry paste to consume hydrogen peroxide during this second stage so that the total weight consumption of hydrogen peroxide during the two stages is between 2% and 5% of the weight of the dry dough.
La nature de l'agent chimique capable d'atteindre les valeurs de pH définies pour la première étape n'est pas critique, l'agent chimique alcalinisant choisi devant toutefois être ni oxydé ni réduit par le peroxyde d'hydrogène.The nature of the chemical agent capable of reaching the pH values defined for the first step is not critical, the basifying chemical agent chosen, however, having to be neither oxidized nor reduced by hydrogen peroxide.
Plusieurs de ces agents chimiques peuvent être simultanément mis en oeuvre à la condition de ne pas réagir entre eux.Several of these chemical agents can be used simultaneously provided that they do not react with each other.
L'hydroxyde de sodium et le carbonate de sodium répondent à la définition ci-dessus, comme aussi, et de préférence, le tripolyphosphate de sodium, le sel de sodium de l'acide éthylènediaminetétracétique et le sel de sodium de l'acide diéthylènetriaminepentaacétique.Sodium hydroxide and sodium carbonate meet the above definition, as also, and preferably, sodium tripolyphosphate, the sodium salt of ethylenediaminetetraacetic acid and the sodium salt of diethylenetriaminepentaacetic acid.
Il est préférable que le pH conserve au cours de cette première étape une valeur la plus constante possible ce qui est réalisable par des techniques connues, par exemple l'emploi de tampons ou l'introduction continue ou intermittente d'un ou plusieurs agents chimiques tels que définis ci-dessus.It is preferable that the pH keeps during this first stage a value as constant as possible which is achievable by known techniques, for example the use of buffers or the continuous or intermittent introduction of one or more chemical agents such as defined above.
Parmi les agents sequestrants des ions métalliques qui conviennent à l'invention, le tripolyphosphate de sodium, le sel de sodium de l'acide éthylènediaminetétracétique et le sel de sodium de l'acide diéthylènetriaminepentaacétique, sont employés de préférence.Among the metal ion sequestering agents which are suitable for the invention, sodium tripolyphosphate, the sodium salt of ethylenediaminetetracetic acid and the sodium salt of diethylenetriaminepentaacetic acid are preferably used.
Ces trois composés, pris isolément ou en mélange peuvent donc agir en même temps comme alcalinisant et comme sequestrant.These three compounds, taken in isolation or as a mixture, can therefore act at the same time as basifying and as sequestering.
La durée de la première étape est généralement inférieure à 4 heures.The duration of the first stage is generally less than 4 hours.
Parmi les agents alcalins nouvant convenir pour atteindre le pH choisi dans la deuxième étape, l'hydroxyde de sodium et le carbonate de sodium conviennent particulièrement bien.Among the new alkaline agents suitable for reaching the pH chosen in the second step, sodium hydroxide and sodium carbonate are particularly suitable.
Dans cette deuxième étape l'hydroxyde de magnésium peut être introduit en l'état ou formé au sein du bain de traitement a partir d'un sel de magnésium comme le chlorure, le nitrate ou le sulfate, dont l'anion est inerte vis-à-vis du peroxyde d'hydrogène.In this second step, magnesium hydroxide can be introduced as it is or formed in the treatment bath from a magnesium salt such as chloride, nitrate or sulfate, the anion of which is inert towards with respect to hydrogen peroxide.
La durée de la deuxième étape est généralement comprise entre 2 et 5 heures.The duration of the second stage is generally between 2 and 5 hours.
La consistance n'est pas un facteur critique pour la réalisation des deux étapes du traitement selon l'invention. Pour des raisons pratiques et économiques il est toujours préférable que la consistance soit comprise entre 3 % et 25 % et mieux entre 5 % et 15 %.Consistency is not a critical factor for carrying out the two stages of treatment according to the invention. For practical and economic reasons it is always preferable that the consistency is between 3% and 25% and better between 5% and 15%.
Dans la première comme dans la deuxième étape, la quanttté de peroxyde d'hydrogène engagée est bien entendu au moins égale à la quantité devant être consommée et est au plus égale généralement à 5 % en poids du poids de pâte sèche, de préférence à 3,5 % environ.In the first as in the second step, the amount of hydrogen peroxide used is of course at least equal to the quantity to be consumed and is generally at most equal to 5% by weight of the weight of dry pulp, preferably 3 , About 5%.
Après la première étape du traitement de l'invention, la pâte peut être séparée d'une façon habituelle de la liqueur du bain et soumise d'une manière connue à une extraction alcaline avant la seconde étape du traitement.After the first stage of the treatment of the invention, the paste can be separated in the usual way from the liquor of the bath and subjected in a known manner to an alkaline extraction before the second stage of the treatment.
Cette extraction alcaline, généralement pratiquée à une température de l'ordre de 90°C à 120°C est effectuée de préférence dans la majorité des cas. Elle reste toutefois facultative et peut même avantageusement ne pas être réalisée en particulier lorsque les conditions choisies pour effectuer la première étape sont telles que le peroxyde d'hydrogène mis en oeuvre dans celle-ci est consommé pratiquement en totalité.This alkaline extraction, generally carried out at a temperature of the order of 90 ° C to 120 ° C, is preferably carried out in the majority of cases. However, it remains optional and may even advantageously not be carried out in particular when the conditions chosen to perform the first step are such that the hydrogen peroxide used in it is consumed almost entirely.
Lorsque les liqueurs des bains des deux étapes sont séparées de la pâte, elles peuvent respectivement être avantageusement utilisées pour contribuer à la constitution de chacun de ces bains dans leur composition initiale.When the liquors of the baths of the two stages are separated from the dough, they can respectively be advantageously used to contribute to the constitution of each of these baths in their initial composition.
La pâte traitée selon l'invention peut être blanchie selon des procédés usuels, dont l'économie et l'efficacité se trouvent améliorés.The pulp treated according to the invention can be bleached according to usual methods, the economy and efficiency of which are improved.
Les conditions définies pour la réalisation de la première étape sont celles qui permettent l'obtention après la seconde étape de pâtes chimiques d'indice KAPPA le plus généralement inférieur à 15 lorsque la pâte chimique à traiter est de la pâte chimique de bois résineux,et une économie globale du traitement particulièrement intéressante que traduit par exemple une efficacité élevée du peroxyde d'hydrogène.The conditions defined for carrying out the first step are those which make it possible to obtain, after the second step, chemical pulps with a KAPPA index most generally less than 15 when the chemical pulp to be treated is chemical pulp of softwoods, and a particularly advantageous overall saving in treatment which is reflected, for example, in the high efficiency of hydrogen peroxide.
Celle-ci est désignée dans ce qui suit par le terme Ef défini comme étant égal à :
Les exemples suivants illustrent le traitement de l'invention. Ils sont donnés à titre indicatif mais non limitatif.The following examples illustrate the treatment of the invention. They are given as an indication but not limiting.
Dans chacun des exemples les quantités des divers composés impliqués sont exprimées en pour cent en poids du poids de la pâte sèche. Echappe bien entendu à cette remarque la consistance de la pâte.In each of the examples, the amounts of the various compounds involved are expressed in percent by weight of the weight of the dry paste. Of course, the consistency of the dough escapes this remark.
Dans chacun des exemples les conditions sont telles que, comme défini plus haut, le pH dans la première étape est compris entre 8,5 et 9,5, le pH dans la deuxième étape comme d'ailleurs dans l'exemple comparatif est au moins égal à 11.In each of the examples, the conditions are such that, as defined above, the pH in the first step is between 8.5 and 9.5, the pH in the second step as elsewhere in the comparative example is at least equal to 11.
Une pâte chimique de bois résineux d'indice KAPPA égal à 28,5 est traitée durant 2 H à 90°C à la consistance de 5 % en présence de 3,4 % de peroxyde d'hydrogène H202 et de 41,4 % de tripolyphosphate de sodium TPP.A chemical pulp of resinous wood with a KAPPA index equal to 28.5 is treated for 2 hours at 90 ° C. at the consistency of 5% in the presence of 3.4% of hydrogen peroxide H 2 0 2 and of 41, 4% sodium tripolyphosphate TPP.
La consommation de H202 est ainsi de 1,9 % dans cette première étape.The consumption of H 2 0 2 is thus 1.9% in this first stage.
Après extraction alcaline pratiquée durant 1 H à 90°C en présence de 20 % d'hydroxyde de sodium NaOH, la pâte, à la consistance de 5 %, est soumise à 90°C et durant 2 heures, à l'action de 2,7 % de H202 en présence de 3,2 % de NaOH et 0,5 % d'hydroxyde de magnésium Mg (OH)2.After alkaline extraction carried out for 1 hour at 90 ° C in the presence of 20% sodium hydroxide NaOH, the dough, with a consistency of 5%, is subjected to 90 ° C and for 2 hours, to the action of 2 , 7% H 2 0 2 in the presence of 3.2% NaOH and 0.5% magnesium hydroxide Mg (OH) 2 .
La consommation de H202 atteint ainsi 1,5 % dans cette deuxième étape.The consumption of H 2 02 thus reaches 1.5% in this second stage.
La consommation globale de H202 est de 3,4 % tandis que l'indice KAPPA de la pâte traitée n'est plus que de 12,5 et que Ef. atteint 4,7.The overall consumption of H 2 02 is 3.4% while the KAPPA index of the treated pulp is only 12.5 and Ef. reaches 4.7.
La même pâte que dans l'exemple 1 est soumise, à 90°C et durant 2 heures, à l'action de 3,4 % de N2O2 en présence de 4 % de NaOH et 0,6 % de Mg (OH)3, le consistance étant de 5 %.The same paste as in Example 1 is subjected, at 90 ° C. and for 2 hours, to the action of 3.4% of N 2 O 2 in the presence of 4% of NaOH and 0.6% of Mg ( OH) 3 , the consistency being 5%.
La consommation de H202 est alors totale mais l'indice KAPPA de la pâte traitée est encore de 25, donc seulement légèrement inférieur à sa valeur initiale.The consumption of H 2 0 2 is then total but the KAPPA index of the treated pulp is still 25, therefore only slightly lower than its initial value.
Ef. est près de 5 fois moins élevé que dans l'exemple 1.Ef. is almost 5 times lower than in Example 1.
La même pâte que dans l'exemple 1, à la même consistance que dans cet exemple, subit
- . une première étape dans les conditions suivantes :
- . une extraction alcaline dans les conditions de l'exemple 1,
- . une seconde étape dans les conditions suivantes :
- . a first step under the following conditions:
- . an alkaline extraction under the conditions of Example 1,
- . a second step under the following conditions:
La consommation de H202 dans la première étape est de 1 %, dans la deuxième étape de 1,2 %, l'indice KAPPA de la pâte traitée n'est plus que de 12,5 et Ef. est 7,5 fois plus élevé que dans l'exemple 2.The consumption of H 2 0 2 in the first stage is 1%, in the second stage of 1.2%, the KAPPA index of the treated pulp is only 12.5 and Ef. is 7.5 times higher than in Example 2.
Une pâte chimique de bois résineux d'indice KAPPA égal à 33 est traitée à la consistance de 5 %, à 90° et durant 1 heure en présence de 0,6 % de H202 et de 17,2 % de TPP.A chemical pulp of resinous wood with a KAPPA index equal to 33 is treated at the consistency of 5%, at 90 ° and for 1 hour in the presence of 0.6% of H 2 0 2 and 17.2% of TPP.
La consommation de H202 est alors totale.The consumption of H 2 0 2 is then total.
La pâte,à la même consistance et sans extraction alcaline, est soumise dans une deuxième étape à l'action de 2,7 % de H202 en présence de 4 % de NaOH et de 0,25 % de Mg (OH)2, à 90°C durant 5 H.The paste, with the same consistency and without alkaline extraction, is subjected in a second step to the action of 2.7% of H 2 O 2 in the presence of 4% of NaOH and of 0.25% of Mg (OH) 2 , at 90 ° C for 5 hours.
La consommation de H202 est encore totale.The consumption of H 2 0 2 is still total.
L'indice KAPPA de la pâte traitée est 3 fois plus faible qu'avant traitement et Ef. est d'environ 7.The KAPPA index of the treated pulp is 3 times lower than before treatment and Ef. is around 7.
En procédant comme dans l'exemple 3 mais en pratiquant l'extraction alcaline à 120°C au lieu de 90°C, l'indice KAPPA de la pâte traitée est de 10,5 avec une consommation globale de H202 de 2,0%. Ef. est alors de près de 9,0.By proceeding as in Example 3 but using alkaline extraction at 120 ° C instead of 90 ° C, the KAPPA index of the treated pulp is 10.5 with an overall consumption of H 2 0 2 of 2 .0%. Ef. is then close to 9.0.
La pâte chimique à traiter de l'exemple 4, à une consistance de 10 %, subit,
- . une première étape dans les conditions suivantes :et sans extraction alcaline intermédiaire,
- . une étape dans les conditions suivantes, toujours à la consistance de 10 % :
- . a first step under the following conditions: and without intermediate alkaline extraction,
- . a step under the following conditions, always at the consistency of 10%:
La consommation de H202 dans la première étape est de 0,3 % elle est totale dans la seconde étape.The consumption of H 2 0 2 in the first stage is 0.3% and it is total in the second stage.
Après traitement la pâte à un indice KAPPA de 15 et Ef. est égal à 5.After treatment, the paste has a KAPPA index of 15 and Ef. is equal to 5.
L'exemple 4 est répété, mais le pH dans la première étape est atteint grâce à l'acide éthytènediaminetétracétique et la soude et est maintenu à 9,5 par addition de NaOH.Example 4 is repeated, but the pH in the first step is reached by means of ethytenediaminetetracetic acid and sodium hydroxide and is maintained at 9.5 by addition of NaOH.
Les résultats de l'exemple 4 sont pratiquement retrouvés.The results of Example 4 are practically found.
Claims (9)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT86420138T ATE32534T1 (en) | 1985-05-29 | 1986-05-27 | TREATMENT OF CHEMICAL PAPER PULP WITH HYDROGEN PEROXIDE IN VIEW OF THEIR BLEACHING. |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8508291A FR2582692B1 (en) | 1985-05-29 | 1985-05-29 | TREATMENT OF CHEMICAL PAPER PULP WITH HYDROGEN PEROXIDE FOR BLEACHING |
| FR8508291 | 1985-05-29 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0208625A1 true EP0208625A1 (en) | 1987-01-14 |
| EP0208625B1 EP0208625B1 (en) | 1988-02-17 |
Family
ID=9319780
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP86420138A Expired EP0208625B1 (en) | 1985-05-29 | 1986-05-27 | Treatment of chemical pulps with hydrogen peroxide in order to bleach them |
Country Status (10)
| Country | Link |
|---|---|
| US (1) | US4734161A (en) |
| EP (1) | EP0208625B1 (en) |
| JP (1) | JPS61275491A (en) |
| AT (1) | ATE32534T1 (en) |
| AU (1) | AU5794486A (en) |
| CA (1) | CA1273756A (en) |
| DE (1) | DE3660024D1 (en) |
| ES (1) | ES8802336A1 (en) |
| FI (1) | FI83239C (en) |
| FR (1) | FR2582692B1 (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0313478A1 (en) * | 1987-10-22 | 1989-04-26 | Elf Atochem S.A. | Process for bleaching pulps |
| EP0402335A2 (en) * | 1989-06-06 | 1990-12-12 | Eka Nobel Ab | Process for bleaching lignocellulose-containing pulps |
| FR2661431A1 (en) * | 1990-04-30 | 1991-10-31 | Atochem | Process for hydrogen peroxide bleaching of high-yield paper pulps |
| WO1995012709A1 (en) * | 1993-11-04 | 1995-05-11 | Solvay Interox (Societe Anonyme) | Process for bleaching a chemical pulp |
| WO1996001922A1 (en) * | 1994-07-11 | 1996-01-25 | Beloit Technologies, Inc. | Method for bleaching wood pulp using hydrogen peroxide |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0642046B2 (en) * | 1987-01-29 | 1994-06-01 | 新王子製紙株式会社 | Support for photographic paper |
| SE9001481L (en) * | 1990-04-23 | 1991-10-24 | Eka Nobel Ab | REDUCTION OF HALOGEN ORGANIC SUBSTANCES IN BLEACHING WASTE |
| US5562740A (en) * | 1995-06-15 | 1996-10-08 | The Procter & Gamble Company | Process for preparing reduced odor and improved brightness individualized, polycarboxylic acid crosslinked fibers |
| CA2373562A1 (en) * | 2001-02-27 | 2002-08-27 | Aileen Reyes Gibson | Eop & ep process for bleaching of chemical pulp |
| US7297225B2 (en) * | 2004-06-22 | 2007-11-20 | Georgia-Pacific Consumer Products Lp | Process for high temperature peroxide bleaching of pulp with cool discharge |
| FR3007044B1 (en) * | 2013-06-13 | 2016-01-15 | Air Liquide | PROCESS FOR TREATING CHEMICAL PAPER PASTES BY OZONE TREATMENT IN THE PRESENCE OF MAGNESIUM IONS |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2038056A1 (en) * | 1969-03-07 | 1971-01-08 | Air Liquide | Stable, clear bleaching bath for paper - pulp |
| FR2537177A1 (en) * | 1982-09-14 | 1984-06-08 | Sca Development Ab | Peroxide-bleaching of cellulose pulp obtd. in high yield |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2865701A (en) * | 1953-12-07 | 1958-12-23 | Nat Distillers Chem Corp | Process of bleaching kraft pulp with alkaline hypochlorite bleach acidifying the pulp containing residual chlorine and then bleaching with alkaline peroxide |
| US4187141A (en) * | 1975-02-24 | 1980-02-05 | Alf Societe Anonyme | Method of producing bleached mechanical pulp |
| JPS583074B2 (en) * | 1975-11-17 | 1983-01-19 | 三菱瓦斯化学株式会社 | Palpuno Kasan Kabutsu Hiyou Hakuhou |
| JPS5545806A (en) * | 1978-09-21 | 1980-03-31 | Oji Paper Co | Peroxide bleaching method of wood pulp |
| US4294575A (en) * | 1979-01-02 | 1981-10-13 | Monsanto Company | Peroxide stabilization |
| JPS5891884A (en) * | 1981-11-27 | 1983-05-31 | 工業技術院長 | Production of high whiteness unbleached pulp |
-
1985
- 1985-05-29 FR FR8508291A patent/FR2582692B1/en not_active Expired
-
1986
- 1986-04-07 US US06/849,157 patent/US4734161A/en not_active Expired - Fee Related
- 1986-05-05 CA CA000508344A patent/CA1273756A/en not_active Expired - Lifetime
- 1986-05-27 DE DE8686420138T patent/DE3660024D1/en not_active Expired
- 1986-05-27 AU AU57944/86A patent/AU5794486A/en not_active Abandoned
- 1986-05-27 EP EP86420138A patent/EP0208625B1/en not_active Expired
- 1986-05-27 AT AT86420138T patent/ATE32534T1/en not_active IP Right Cessation
- 1986-05-28 ES ES555395A patent/ES8802336A1/en not_active Expired
- 1986-05-28 FI FI862257A patent/FI83239C/en not_active IP Right Cessation
- 1986-05-29 JP JP61124600A patent/JPS61275491A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2038056A1 (en) * | 1969-03-07 | 1971-01-08 | Air Liquide | Stable, clear bleaching bath for paper - pulp |
| FR2537177A1 (en) * | 1982-09-14 | 1984-06-08 | Sca Development Ab | Peroxide-bleaching of cellulose pulp obtd. in high yield |
Non-Patent Citations (2)
| Title |
|---|
| ABSTRACT BULLETIN OF THE INSTITUTE OF PAPER CHEMISTRY, vol. 55, no. 8, février 1985, page 936, abrégé no. 8870, Appleton, Wisconsin, US; A. ABOU-STATE et al.: "Effects of pH on hydrogen peroxide bleaching of kraft pulp from bagasse", & PAPIER CARTON CELLULOSE 33, no. 8/9: 51-53 * |
| TAPPI JOURNAL, vol. 65, no. 8, septembre 1982, pages 107-111, Atlanta, Georgia, US; M. RUHANEN et al.: "First-stage bleaching of softwood kraft pulp with peroxide, instead of chlorine" * |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0313478A1 (en) * | 1987-10-22 | 1989-04-26 | Elf Atochem S.A. | Process for bleaching pulps |
| FR2622221A1 (en) * | 1987-10-22 | 1989-04-28 | Atochem | PROCESS FOR BLEACHING PASTA |
| EP0402335A2 (en) * | 1989-06-06 | 1990-12-12 | Eka Nobel Ab | Process for bleaching lignocellulose-containing pulps |
| EP0402335A3 (en) * | 1989-06-06 | 1991-10-23 | Eka Nobel Ab | Process for bleaching lignocellulose-containing pulps |
| EP0402335B1 (en) * | 1989-06-06 | 1993-11-10 | Eka Chemicals AB | Process for bleaching lignocellulose-containing pulps |
| FR2661431A1 (en) * | 1990-04-30 | 1991-10-31 | Atochem | Process for hydrogen peroxide bleaching of high-yield paper pulps |
| EP0514609A1 (en) * | 1990-04-30 | 1992-11-25 | Elf Atochem S.A. | Process for hydrogen peroxide bleaching of high-yield pulps |
| US5296100A (en) * | 1990-04-30 | 1994-03-22 | Atochem | H2 O2 /alkaline bleaching of wood pulps |
| WO1995012709A1 (en) * | 1993-11-04 | 1995-05-11 | Solvay Interox (Societe Anonyme) | Process for bleaching a chemical pulp |
| BE1007700A3 (en) * | 1993-11-04 | 1995-10-03 | Solvay Interox | Method of laundering of chemical pulp. |
| WO1996001922A1 (en) * | 1994-07-11 | 1996-01-25 | Beloit Technologies, Inc. | Method for bleaching wood pulp using hydrogen peroxide |
Also Published As
| Publication number | Publication date |
|---|---|
| CA1273756A (en) | 1990-09-11 |
| FI83239B (en) | 1991-02-28 |
| DE3660024D1 (en) | 1988-03-24 |
| FI862257A (en) | 1986-11-30 |
| JPS61275491A (en) | 1986-12-05 |
| EP0208625B1 (en) | 1988-02-17 |
| ES555395A0 (en) | 1987-05-01 |
| ATE32534T1 (en) | 1988-03-15 |
| FR2582692A1 (en) | 1986-12-05 |
| JPH0156194B2 (en) | 1989-11-29 |
| FI862257A0 (en) | 1986-05-28 |
| FR2582692B1 (en) | 1987-12-11 |
| AU5794486A (en) | 1986-12-04 |
| US4734161A (en) | 1988-03-29 |
| ES8802336A1 (en) | 1987-05-01 |
| FI83239C (en) | 1991-06-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0578305B1 (en) | Process of delignification of a chemical pulp | |
| EP0208625B1 (en) | Treatment of chemical pulps with hydrogen peroxide in order to bleach them | |
| EP0040873B2 (en) | Process for the regeneration of waste paper | |
| FR2467261A1 (en) | BLANCHING OF LIGNOCELLULOSIC MATERIAL USING PEROXIDE-CONTAINING BLEACHING AGENTS | |
| CA1206704A (en) | Treatment of chemical pulp | |
| FR2641010A1 (en) | ||
| EP0148712B1 (en) | Process for bleaching paper pulps with hydrogen peroxide | |
| FR2661431A1 (en) | Process for hydrogen peroxide bleaching of high-yield paper pulps | |
| FR2639371A1 (en) | PROCESS FOR WHITENING PASTA PULP | |
| BE1004674A3 (en) | Method of laundering of chemical pulp and application of the method of laundering pulp kraft. | |
| EP0446110B1 (en) | Process for producing bleached high-yield pulps | |
| CA2200486C (en) | Delignification and bleaching process for chemical paper pulp | |
| FR2483479A1 (en) | PROCESS FOR DELIGNIFYING AND / OR BLEACHING OXYGENIC GAS CELLULOSE PULP | |
| FR2910027A1 (en) | PROCESS FOR WHITENING CHEMICAL STRIPPING PASTES BY FINAL OZONE TREATMENT AT HIGH TEMPERATURE | |
| EP3008240B1 (en) | Method for treating chemical pulps by treatment with ozone in the presence of magnesium ions | |
| EP0351330B1 (en) | Process for manufacturing bleached chemithermomechanical pulps | |
| FR2553444A1 (en) | HYPOCHLORITE TREATMENT OF CHEMICAL PAPER PULP | |
| FR2568605A1 (en) | IMPROVEMENTS ON DELIGNIFICATION OF PAPER PULP. | |
| FR2593527A1 (en) | Process for bleaching mechanical pulps | |
| FR2626020A1 (en) | Improved process for bleaching cellulose fibres with the aid of hydrogen peroxide in alkaline medium | |
| BE1005800A3 (en) | Method for the delignification and bleaching of a chemical paper pulp | |
| BE1005094A3 (en) | Method for preserving the mechanical resistance characteristics of chemicalpaper pulps and application of said method to the bleaching anddelignification of Kraft pulps | |
| WO2012028800A1 (en) | Process for the delignification and bleaching of paper pulp using active hydrogen peroxide | |
| BE656601A (en) | ||
| BE1011129A4 (en) | Delignification continuous process and / or money virgin pulp chemical or recycled. |
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: 19860530 |
|
| AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AT BE DE FR IT SE |
|
| 17Q | First examination report despatched |
Effective date: 19870714 |
|
| GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
| AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AT BE DE FR IT SE |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRE;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.SCRIBED TIME-LIMIT Effective date: 19880217 Ref country code: AT Effective date: 19880217 |
|
| REF | Corresponds to: |
Ref document number: 32534 Country of ref document: AT Date of ref document: 19880315 Kind code of ref document: T |
|
| REF | Corresponds to: |
Ref document number: 3660024 Country of ref document: DE Date of ref document: 19880324 |
|
| BERE | Be: lapsed |
Owner name: ATOCHEM Effective date: 19880531 |
|
| PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
| 26N | No opposition filed | ||
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: BE Effective date: 19890531 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 19940511 Year of fee payment: 9 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: SE Payment date: 19940517 Year of fee payment: 9 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 19940524 Year of fee payment: 9 |
|
| EAL | Se: european patent in force in sweden |
Ref document number: 86420138.9 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SE Effective date: 19950528 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Effective date: 19960201 |
|
| EUG | Se: european patent has lapsed |
Ref document number: 86420138.9 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Effective date: 19960229 |
|
| REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |
|
| REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |