NO853688L - PROCEDURE FOR DELIGNIFICATION OF SULPHATE CELLULOS. - Google Patents
PROCEDURE FOR DELIGNIFICATION OF SULPHATE CELLULOS.Info
- Publication number
- NO853688L NO853688L NO853688A NO853688A NO853688L NO 853688 L NO853688 L NO 853688L NO 853688 A NO853688 A NO 853688A NO 853688 A NO853688 A NO 853688A NO 853688 L NO853688 L NO 853688L
- Authority
- NO
- Norway
- Prior art keywords
- oxygen
- delignification
- cellulose
- hydrogen peroxide
- weight
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims abstract description 11
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 title claims abstract description 9
- 229920002678 cellulose Polymers 0.000 title claims description 32
- 229910021653 sulphate ion Inorganic materials 0.000 title description 5
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 41
- 239000001301 oxygen Substances 0.000 claims abstract description 41
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 41
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims abstract description 28
- 230000007935 neutral effect Effects 0.000 claims abstract description 3
- 235000010980 cellulose Nutrition 0.000 claims description 31
- 239000001913 cellulose Substances 0.000 claims description 21
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 15
- 239000000463 material Substances 0.000 claims description 5
- 238000005406 washing Methods 0.000 claims description 3
- 241000294754 Macroptilium atropurpureum Species 0.000 claims description 2
- 230000002378 acidificating effect Effects 0.000 description 5
- 235000011121 sodium hydroxide Nutrition 0.000 description 4
- 239000003513 alkali Substances 0.000 description 3
- 229920005610 lignin Polymers 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 239000002253 acid Substances 0.000 description 2
- 238000004061 bleaching Methods 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- ZZUFCTLCJUWOSV-UHFFFAOYSA-N furosemide Chemical compound C1=C(Cl)C(S(=O)(=O)N)=CC(C(O)=O)=C1NCC1=CC=CO1 ZZUFCTLCJUWOSV-UHFFFAOYSA-N 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- LSNNMFCWUKXFEE-UHFFFAOYSA-L sulfite Chemical compound [O-]S([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-L 0.000 description 2
- 239000002351 wastewater Substances 0.000 description 2
- 229920003043 Cellulose fiber Polymers 0.000 description 1
- 201000004624 Dermatitis Diseases 0.000 description 1
- 229920002488 Hemicellulose Polymers 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 208000010668 atopic eczema Diseases 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 125000000837 carbohydrate group Chemical group 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000004182 chemical digestion Methods 0.000 description 1
- 238000005660 chlorination reaction Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000002845 discoloration Methods 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 238000002203 pretreatment Methods 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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
- D21C9/1057—Multistage, with compounds cited in more than one sub-group D21C9/10, D21C9/12, D21C9/16
Abstract
Description
Oppfinnelsen vedrører en alkalisk delignifisering av sulfatcelluloser med oksygen, hvor det går foran en behandling med oksygen og hydrogenperoksyd i surt medium. The invention relates to an alkaline delignification of sulphate celluloses with oxygen, which is preceded by a treatment with oxygen and hydrogen peroxide in an acidic medium.
De på kjemisk vei fremstilte celluloser, slik de f.eks. fremkommer fra sulfittfremgangsmåten eller i alkaliske natrium- eller sulfatfremgangsmåter, inneholder ved siden av hovedbestanddelen cellulose dessuten mindre mengder lignin, hemicelluloser og noen andre bestanddeler. De nevnte følgestoffer av cellulosen, fremfor alt lignin, be-virker misfarging av cellulosen og derav fremstilte produkter. The chemically produced celluloses, as they e.g. produced from the sulphite process or in alkaline sodium or sulphate processes, besides the main component cellulose also contains smaller amounts of lignin, hemicelluloses and some other components. The aforementioned by-products of the cellulose, above all lignin, cause discoloration of the cellulose and products made from it.
For fra cellulose å fremstille papir eller andre produkterTo make paper or other products from cellulose
av høy hvithet, som ikke tenderer til gulfarging, er det nødvendig en fjerning av de etter den kjemiske oppslutning gjenblivne følgestoffer ved hjelp av en bleking. of high whiteness, which does not tend to yellow, it is necessary to remove the by-products remaining after the chemical digestion by means of bleaching.
Ved anvendelse av oksygen og alkali til delignifisering av ubleket cellulose, er det ikk hensiktsmessig å fjerne mer enn halvparten av det i cellulosen enda tilstedeværende ligning. Under betingelsene av oksygen-delignifisering i alkalisk medium, kommer det nemlig en for intens behand- When using oxygen and alkali for delignification of unbleached cellulose, it is not appropriate to remove more than half of the equation still present in the cellulose. Under the conditions of oxygen delignification in an alkaline medium, there is a too intense treat-
ling av cellulosen til en avbygning av kullhydratkjedene og dermed til et uønsket tap av fastheten av de resulterende cellulosefibre. For unngåelse av økologisk belastning med klorerte forbindelser fra avvann fra det tidl lgere ute-lukkende anvendte kloreringstrinnet, er det imidlertid ønskelig i størst mulig grad bare å anvende oksygen eller oksygenholdige forbindelser til delignif isering . Delignif isering. 11 og bleking ved den samtidig innvirkning av oksygen og hydrogenperoksyd i surt medium fører ved sulfittcelluloser til gode resultater, slik det kan utledes fra tysk patent- ling of the cellulose to a breakdown of the carbohydrate chains and thus to an undesirable loss of the firmness of the resulting cellulose fibres. In order to avoid ecological burden with chlorinated compounds from waste water from the previously exclusively used chlorination step, it is however desirable to the greatest extent possible only to use oxygen or oxygen-containing compounds for delignification. Delignification. 11 and bleaching by the simultaneous action of oxygen and hydrogen peroxide in an acidic medium leads to good results with sulphite celluloses, as can be deduced from German patent
søknad P 34 28 352 .8 . application P 34 28 352 .8 .
For også ved sulfatcelluloser å oppnå en best mulig lignin-fjerning ved samtidig gode viskositetsverdier er det ifølge DE-OS 32 13 856 nødvendig å forbehandle den ublekede cellulose før den alkaliske oksygen-delignifisering med '. NC>2 og oksygen. Anvendelsen av NC>2 krever imidlertid en relativ høy konsistens og er også forbundet med de kjente problemer, som fremkommer ved de kjemiske egenskaper av NC>2. In order to achieve the best possible lignin removal with good viscosity values, also with sulphate celluloses, according to DE-OS 32 13 856 it is necessary to pre-treat the unbleached cellulose before the alkaline oxygen delignification with '. NC>2 and oxygen. The use of NC>2, however, requires a relatively high consistency and is also associated with the known problems that arise from the chemical properties of NC>2.
Oppfinnelsens oppgave er å tilveiebringe en fremgangsmåte til oppnåelse av en høy delignifiseringsgrad ved behandling av cellulosen med oksygen ved samtidig høye resulterende fastheter. The task of the invention is to provide a method for achieving a high degree of delignification by treating the cellulose with oxygen at the same time high resulting strengths.
Oppfinnelsens gjenstand er en totrinns-fremgangsmåte til delignifisering av under alkaliske eller nøytrale betingelser frembragte celluloser (sulfatcelluloser) med oksygen og hydrogen-peroksyd, idet fremgangsmåten erkarakterisertved at cellulosen forbehandles ved en pH-verdi under 5 samtidig med oksygen og hydrogen-peroksyd, og deretter videre delignifiseres med oksygen i alkalisk medium. The object of the invention is a two-stage method for delignification of celluloses produced under alkaline or neutral conditions (sulphate celluloses) with oxygen and hydrogen peroxide, the method being characterized in that the cellulose is pretreated at a pH value below 5 simultaneously with oxygen and hydrogen peroxide, and then further delignified with oxygen in an alkaline medium.
Ved kombinasjonen av den alkaliske oksygen-delignifisering med forbehandlingen oppnår man Kappa-verdier som ligger lavere enn de som oppnås med oksygen-delignifisering. Samtidig synker imidlertid viskositeten overraskende ikke så sterkt og også ved rivlengder viser de ifølge oppfinnelsen delignifiserte celluloser tydelig bedre verdier enn de entrinnet med oksygen i alkalisk medium behandlede celluloser. By combining the alkaline oxygen delignification with the pretreatment, Kappa values are obtained that are lower than those obtained with oxygen delignification. At the same time, however, the viscosity surprisingly does not drop so strongly and even at tear lengths, the delignified celluloses according to the invention clearly show better values than the celluloses treated in one step with oxygen in an alkaline medium.
Også ved høy delignifiseringsgrad ligger de resulterende fasthetsverdier på et høyt nivå. Even with a high degree of delignification, the resulting firmness values are at a high level.
Fortrinnsvis lar man oksygen og hydrogen-peroksyd bare i kort tid, dvs. 60 sekunder til 60 minutter, fortrinnsvis 4-30 minutter, innvirke på cellulosen i surt medium. Preferably, oxygen and hydrogen peroxide are only allowed to act on the cellulose in an acidic medium for a short time, i.e. 60 seconds to 60 minutes, preferably 4-30 minutes.
Man arbeider med et oksygentrykk fra 0,03-0,5 MPa, en oksygenkonsentrasjon på 0,1-5 vekt-%, en hydrogen-peroksyd-konsentrasjn på 0,1-3 vekt-%, fortrinnsvis inntil 2 vekt-%, respektivt referert til atro cellulose, en stofftetthet fra 5-40%, fortrinnsvis 8-25% i pH-området fdra 1-4, fortrinnsvis 1,5-3, ved en temperatur fra 60-120°C, fortrinnsvis på 80-100°C. One works with an oxygen pressure of 0.03-0.5 MPa, an oxygen concentration of 0.1-5% by weight, a hydrogen peroxide concentration of 0.1-3% by weight, preferably up to 2% by weight, respectively referred to atro cellulose, a material density of 5-40%, preferably 8-25% in the pH range of 1-4, preferably 1.5-3, at a temperature of 60-120°C, preferably of 80-100 °C.
Oksygendelignifiseringen i alkalisk medium i nærvær av NaOH som base foregår i henhold til teknikkens stand ved 90-120°C og et oksygentrykk på 0,1-0,5 MPa. The oxygen delignification in an alkaline medium in the presence of NaOH as a base takes place according to the state of the art at 90-120°C and an oxygen pressure of 0.1-0.5 MPa.
Vekslingen mellom den sure forbehandling og den alkaliske delignifisering med oksygen kan gjennomføres ved innkobling av en diffusjonsvask, således at det kreves bare litt mer damp og vaskevann. Arbeidsmåten uten mellomvasking, hvor det til nøytralisering av det sure trinn kreves mer alkali, har derimot den fordel å kunne konsumere så vel overskytende oksygen som også hydrogen-peroksyd fra forbehandlings-trinnet i de ytterligere trinn. Dampbehovet økes derved ikke i forhold til standard-delignifisering. Det høyere alkalibehov lar seg dekke fra kaustifisert hvitlut. Da avvannet fra oksygentrinnet tilbakeføres, kommer det totalt ikke til høyere kjemikalibehov. Fordelene ved denne forbehandling med oksygen og hydrogen-peroksyd i nærvær av syrer forklarer følgende eksempler: The alternation between the acid pretreatment and the alkaline delignification with oxygen can be carried out by switching on a diffusion wash, so that only a little more steam and wash water is required. The method of working without intermediate washing, where more alkali is required to neutralize the acidic step, has the advantage of being able to consume both excess oxygen and also hydrogen peroxide from the pretreatment step in the further steps. The steam requirement is thereby not increased compared to standard delignification. The higher alkali requirement can be met from causticized white liquor. As the wastewater from the oxygen stage is recycled, there is no higher chemical requirement in total. The advantages of this pretreatment with oxygen and hydrogen peroxide in the presence of acids are explained by the following examples:
Eksemgel_lEczema gel_l
a) Furusulfat-cellulose med Kappa-tall 29,5 behandles' ved 100°C og 12% stofftetthet 5 minutter ved 0,3 MPa med a) Furose sulfate cellulose with a Kappa number of 29.5 is treated at 100°C and 12% material density for 5 minutes at 0.3 MPa with
0,3 vekt-% oksygen og 0,6 vekt-% hydrogen-peroksyd ved pH 1,8. Etter en vasking av cellulosen utgjør^Kappa-tallet enda 22,8, viskositeten 1210 dm<3>/kg. 0.3% by weight oxygen and 0.6% by weight hydrogen peroxide at pH 1.8. After washing the cellulose, the Kappa number is still 22.8, the viscosity 1210 dm<3>/kg.
I annet behandlingstrinn foregår ved 115°C, 12% stofftetthet og 90 minutters oppholdstid en oksygen-delignifisering under 0,5 MPa C^-trykk i nærvær av 4 vekt-% NaOH og 0,5 vekt-% MgSO^. Derved fremkommer en oppslutnings-grad på Kappa på 8,9. Cellulosen har følgende egenskaper: b) Gjennomfører man oksygen-delignifiseringen som angitt under a) , imidlertid uten sur C^/I^C^-forbehandling, In the second treatment step, oxygen delignification takes place at 115°C, 12% material density and 90 minute residence time under 0.5 MPa C^ pressure in the presence of 4% by weight NaOH and 0.5% by weight MgSO^. This results in a Kappa approval rating of 8.9. The cellulose has the following properties: b) The oxygen delignification is carried out as stated under a), however without acidic C^/I^C^ pretreatment,
så får man følgende resultat::;:then the following result is obtained::;:
Eksemp_el_2 Example_el_2
a) Furusulfat-cellulose med et Kappa-tall på 31,5 behandles ved 90°C og 14% stofftetthet ved 0,3 MPa med 0,4 vekt-% a) Furose sulfate cellulose with a Kappa number of 31.5 is treated at 90°C and 14% material density at 0.3 MPa with 0.4% by weight
oksygen og 0,5 vekt-% ^ 2^ 2 ^ ^ mi-nutter" Ve<^ tilsetning av 0,7 vekt-% H-jSO^ ble det innstilt pH 2,2. oxygen and 0.5% by weight ^ 2^ 2 ^ ^ mi-nuts" Ve<^ addition of 0.7% by weight H-jSO^ the pH was adjusted to 2.2.
Etter forbehandlingen vaskes ikke, men alkaliseres ved tilsetning av 5% NaOH. Oksygentrykket samt temperaturen økes til 0,5 MPa og 120°C. Ved kjemikalitilsetningen nedsetter konsistensen seg til 12%. Oppholdstiden utgjør 90 minutter. Den således delignifiserte cellulose har følgende egenskaper: b) Delignifiserer man samme cellulose med oksygen under samme betingelser (imidlertid tilsvarende den til nøy-traliseringen ved a) nødvendige mindre natronlutmengde), så fremkommer en cellulose med Kappa-tall 14,3. After the pre-treatment, it is not washed, but alkalized by the addition of 5% NaOH. The oxygen pressure and temperature are increased to 0.5 MPa and 120°C. With the addition of chemicals, the consistency drops to 12%. The length of stay is 90 minutes. The thus delignified cellulose has the following properties: b) If the same cellulose is delignified with oxygen under the same conditions (however corresponding to that of the neutralization by a) smaller amount of caustic soda required), a cellulose with a Kappa number of 14.3 is produced.
Den har følgende egenskaper:It has the following properties:
Claims (3)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19843446301 DE3446301A1 (en) | 1984-12-19 | 1984-12-19 | METHOD FOR DELIGNIFYING SULFATE CELLS |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| NO853688L true NO853688L (en) | 1986-06-20 |
Family
ID=6253194
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| NO853688A NO853688L (en) | 1984-12-19 | 1985-09-20 | PROCEDURE FOR DELIGNIFICATION OF SULPHATE CELLULOS. |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP0185858B1 (en) |
| JP (1) | JPS61146894A (en) |
| AT (1) | ATE33998T1 (en) |
| DE (2) | DE3446301A1 (en) |
| FI (1) | FI853492L (en) |
| NO (1) | NO853688L (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0863251A1 (en) * | 1997-03-04 | 1998-09-09 | Oji Paper Co., Ltd. | Process for producing bleached pulp |
| US5919238A (en) * | 1998-03-04 | 1999-07-06 | Ford Global Technologies, Inc. | Method for aligning a vehicle suspension |
| WO2015155924A1 (en) | 2014-04-08 | 2015-10-15 | パナソニックＩｐマネジメント株式会社 | Organic el element and lighting device |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3719552A (en) * | 1971-06-18 | 1973-03-06 | American Cyanamid Co | Bleaching of lignocellulosic materials with oxygen in the presence of a peroxide |
| SE420430B (en) * | 1978-02-17 | 1981-10-05 | Mo Och Domsjoe Ab | PROCEDURE FOR WHEATING AND EXTRACTION OF LIGNOCELLULOSALLY MATERIALS WITH PEROXID CONTAINING BLACKS |
| US4372812A (en) * | 1978-04-07 | 1983-02-08 | International Paper Company | Chlorine free process for bleaching lignocellulosic pulp |
| JPS58501383A (en) * | 1981-09-04 | 1983-08-18 | ウェヤ−ハウザ−・カンパニ− | Treatment of pulp with oxygen |
| DE3207157C1 (en) * | 1982-02-27 | 1983-06-09 | Degussa Ag, 6000 Frankfurt | Process for the production of semi-bleached cellulose |
-
1984
- 1984-12-19 DE DE19843446301 patent/DE3446301A1/en not_active Withdrawn
-
1985
- 1985-09-12 FI FI853492A patent/FI853492L/en not_active Application Discontinuation
- 1985-09-20 NO NO853688A patent/NO853688L/en unknown
- 1985-09-25 AT AT85112163T patent/ATE33998T1/en active
- 1985-09-25 DE DE8585112163T patent/DE3562496D1/en not_active Expired
- 1985-09-25 EP EP85112163A patent/EP0185858B1/en not_active Expired
- 1985-12-16 JP JP60281267A patent/JPS61146894A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| DE3562496D1 (en) | 1988-06-09 |
| ATE33998T1 (en) | 1988-05-15 |
| JPS61146894A (en) | 1986-07-04 |
| FI853492A0 (en) | 1985-09-12 |
| EP0185858A1 (en) | 1986-07-02 |
| FI853492L (en) | 1986-06-20 |
| DE3446301A1 (en) | 1986-06-19 |
| EP0185858B1 (en) | 1988-05-04 |
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