NO156529B - PROCEDURE FOR CELLULOSE CARBAMATE COLLECTION. - Google Patents
PROCEDURE FOR CELLULOSE CARBAMATE COLLECTION. Download PDFInfo
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- NO156529B NO156529B NO83832928A NO832928A NO156529B NO 156529 B NO156529 B NO 156529B NO 83832928 A NO83832928 A NO 83832928A NO 832928 A NO832928 A NO 832928A NO 156529 B NO156529 B NO 156529B
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- Prior art keywords
- solution
- carbamate
- cellulose
- precipitation
- cellulose carbamate
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- KXDHJXZQYSOELW-UHFFFAOYSA-M Carbamate Chemical compound NC([O-])=O KXDHJXZQYSOELW-UHFFFAOYSA-M 0.000 title claims description 48
- 229920002678 cellulose Polymers 0.000 title claims description 44
- 239000001913 cellulose Substances 0.000 title claims description 44
- 238000000034 method Methods 0.000 title claims description 26
- 239000000243 solution Substances 0.000 claims description 47
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 30
- 238000001556 precipitation Methods 0.000 claims description 25
- 239000000835 fiber Substances 0.000 claims description 24
- 239000003513 alkali Substances 0.000 claims description 10
- 150000001768 cations Chemical class 0.000 claims description 10
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 claims description 9
- 229910052938 sodium sulfate Inorganic materials 0.000 claims description 7
- 235000011152 sodium sulphate Nutrition 0.000 claims description 7
- 229910052782 aluminium Inorganic materials 0.000 claims description 5
- 239000011777 magnesium Substances 0.000 claims description 5
- 239000011701 zinc Substances 0.000 claims description 5
- 229910052725 zinc Inorganic materials 0.000 claims description 5
- 239000011575 calcium Substances 0.000 claims description 4
- 229910052791 calcium Inorganic materials 0.000 claims description 4
- OSGAYBCDTDRGGQ-UHFFFAOYSA-L calcium sulfate Chemical compound [Ca+2].[O-]S([O-])(=O)=O OSGAYBCDTDRGGQ-UHFFFAOYSA-L 0.000 claims description 4
- 229910052749 magnesium Inorganic materials 0.000 claims description 4
- 239000007864 aqueous solution Substances 0.000 claims description 3
- 239000011734 sodium Substances 0.000 claims description 3
- 229910052943 magnesium sulfate Inorganic materials 0.000 claims description 2
- NWONKYPBYAMBJT-UHFFFAOYSA-L zinc sulfate Chemical compound [Zn+2].[O-]S([O-])(=O)=O NWONKYPBYAMBJT-UHFFFAOYSA-L 0.000 claims description 2
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims 1
- 229940095672 calcium sulfate Drugs 0.000 claims 1
- 229940091250 magnesium supplement Drugs 0.000 claims 1
- 229910000368 zinc sulfate Inorganic materials 0.000 claims 1
- 229960001763 zinc sulfate Drugs 0.000 claims 1
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 24
- 229920000297 Rayon Polymers 0.000 description 10
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 6
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 6
- 239000004202 carbamide Substances 0.000 description 6
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- OWIKHYCFFJSOEH-UHFFFAOYSA-N Isocyanic acid Chemical compound N=C=O OWIKHYCFFJSOEH-UHFFFAOYSA-N 0.000 description 4
- XLJMAIOERFSOGZ-UHFFFAOYSA-N anhydrous cyanic acid Natural products OC#N XLJMAIOERFSOGZ-UHFFFAOYSA-N 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 4
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 3
- 235000008331 Pinus X rigitaeda Nutrition 0.000 description 3
- 235000011613 Pinus brutia Nutrition 0.000 description 3
- 241000018646 Pinus brutia Species 0.000 description 3
- ZOOODBUHSVUZEM-UHFFFAOYSA-N ethoxymethanedithioic acid Chemical compound CCOC(S)=S ZOOODBUHSVUZEM-UHFFFAOYSA-N 0.000 description 3
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- 230000001376 precipitating effect Effects 0.000 description 3
- 238000009987 spinning Methods 0.000 description 3
- 239000012991 xanthate Substances 0.000 description 3
- 239000008096 xylene Substances 0.000 description 3
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 description 2
- 229910021529 ammonia Inorganic materials 0.000 description 2
- 230000008021 deposition Effects 0.000 description 2
- BUACSMWVFUNQET-UHFFFAOYSA-H dialuminum;trisulfate;hydrate Chemical compound O.[Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O BUACSMWVFUNQET-UHFFFAOYSA-H 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- ZFSLODLOARCGLH-UHFFFAOYSA-N isocyanuric acid Chemical compound OC1=NC(O)=NC(O)=N1 ZFSLODLOARCGLH-UHFFFAOYSA-N 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- LSNNMFCWUKXFEE-UHFFFAOYSA-L sulfite Chemical compound [O-]S([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-L 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- ULUZGMIUTMRARO-UHFFFAOYSA-N (carbamoylamino)urea Chemical compound NC(=O)NNC(N)=O ULUZGMIUTMRARO-UHFFFAOYSA-N 0.000 description 1
- 229920000875 Dissolving pulp Polymers 0.000 description 1
- JLVVSXFLKOJNIY-UHFFFAOYSA-N Magnesium ion Chemical compound [Mg+2] JLVVSXFLKOJNIY-UHFFFAOYSA-N 0.000 description 1
- 241000218657 Picea Species 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 229940037003 alum Drugs 0.000 description 1
- DIZPMCHEQGEION-UHFFFAOYSA-H aluminium sulfate (anhydrous) Chemical group [Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O DIZPMCHEQGEION-UHFFFAOYSA-H 0.000 description 1
- DNEHKUCSURWDGO-UHFFFAOYSA-N aluminum sodium Chemical compound [Na].[Al] DNEHKUCSURWDGO-UHFFFAOYSA-N 0.000 description 1
- 239000001175 calcium sulphate Substances 0.000 description 1
- 235000011132 calcium sulphate Nutrition 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 150000003841 chloride salts Chemical class 0.000 description 1
- -1 chlorides Chemical class 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910001425 magnesium ion Inorganic materials 0.000 description 1
- 235000019341 magnesium sulphate Nutrition 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- 229910021653 sulphate ion Inorganic materials 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
- 235000009529 zinc sulphate Nutrition 0.000 description 1
- 239000011686 zinc sulphate Substances 0.000 description 1
Landscapes
- Polysaccharides And Polysaccharide Derivatives (AREA)
Description
Foreliggende oppfinnelse vedrører en fremgangsmåte for utfelling av et cellulosederivat fra en alkalioppløsning. Spesielt angår oppfinnelsen en fremgangsmåte for utfelling av cellulosekarbamat fra dens alkalioppløsning, i form av fiber eller film. The present invention relates to a method for precipitating a cellulose derivative from an alkali solution. In particular, the invention relates to a method for precipitating cellulose carbamate from its alkali solution, in the form of fiber or film.
I de finske patenter nr. 61.033 og 62.318 beskrives en fremgangsmåte for fremstilling av et alkalioppløselig cellulosederivat fra cellulose og urea ved forhøyet temperatur. Fremgangsmåten er basert på det faktum at når urea opp-varmes til sitt smeltepunkt eller til en høyere temperatur, begynner det å dekomponere til isocyansyre og ammoniakk. Isocyansyre er i seg selv ingen særlig stabil forbindelse: den har tendens til å bli trimerisert til isocyanursyre. Videre, isocyansyre har tendens til å reagere med urea, hvorved biuret dannes. Isocyansyre reagerer også med cellulose under dannelse av en alkalioppløselig cellulose-forbindelse som betegnes cellulosekarbamat. Reaksjonen kan skrives som følger: In the Finnish patents no. 61,033 and 62,318, a method for the production of an alkali-soluble cellulose derivative from cellulose and urea at an elevated temperature is described. The method is based on the fact that when urea is heated to its melting point or to a higher temperature, it begins to decompose into isocyanic acid and ammonia. Isocyanic acid itself is not a very stable compound: it tends to be trimerized to isocyanuric acid. Furthermore, isocyanic acid tends to react with urea, thereby forming biurea. Isocyanic acid also reacts with cellulose to form an alkali-soluble cellulose compound called cellulose carbamate. The reaction can be written as follows:
Den således fremstilte forbindelse, cellulosekarbamat, kan tørkes etter vasking og lagres selv over lengre tidsrom, eller den kan oppløses i en vandig alkalioppløsning for fremstilling av for eksempel fibre. Fra denne oppløsning kan det fremstilles cellulosekarbamatfibre eller -filmer ved spinning eller ved ekstrudering, på lignende måte som i viskosefremstillingsprosessen. Den holdbare kvalitet og transportevne for cellulosekarbamat i tørr tilstand gir en stor fordel sammenlignet med cellulosexantatet i viskoseprosessen, hvilken forbindelse ikke kan lagres eller tran-sporteres, heller ikke i oppløsningsform. The thus produced compound, cellulose carbamate, can be dried after washing and stored even for longer periods of time, or it can be dissolved in an aqueous alkali solution for the production of fibers, for example. From this solution, cellulose carbamate fibers or films can be produced by spinning or by extrusion, in a similar way to the viscose manufacturing process. The durable quality and transportability of cellulose carbamate in the dry state gives a great advantage compared to the cellulose xanthate in the viscose process, which compound cannot be stored or transported, not even in solution form.
Dersom det for eksempel er behov for kontinuerlig fiber eller filament fremstilt fra cellulosekarbamat egnet for tekstilanvendelse, er det nødvendig først å fremstille en oppløsning av karbamat i en vandig oppløsning av alkali, f.eks. natriumhydroksyd. Deretter er det mulig å utfelle fra denne oppløsning fiber eller film på samme måte som ved fremstilling av viskosefibre hvor cellulose regenereres fra en NaOH-oppløsning av cellulosexantat. I viskoseprosessen blir en xantatoppløsning som regel spunnet i et utfellingsbad som inneholder fortynnet svovelsyre og natriumsulfat. If, for example, there is a need for continuous fiber or filament produced from cellulose carbamate suitable for textile use, it is necessary to first prepare a solution of carbamate in an aqueous solution of alkali, e.g. sodium hydroxide. It is then possible to precipitate fiber or film from this solution in the same way as in the production of viscose fibers where cellulose is regenerated from a NaOH solution of cellulose xanthate. In the viscose process, a xanthate solution is usually spun in a precipitation bath containing dilute sulfuric acid and sodium sulfate.
Selvom utfellingen av cellulosekarbamat i svovelsyre ligner utfellingsprosessen i viskosemetoden gjelder det et helt forskjellig prinsipp. Cellulosekarbamat er stabilt under sure betingelser og dekomponerer derfor ikke til cellulose ved utfelling, som i viskoseprosessen. Ved å bringe alkalioppløsningen av karbamatet i kontakt med svovelsyre, bevirkes imidlertid utfelling av cellulosekarbamatet og samtidig dannes natriumsulfat og natriumhydroksyd nøy-traliseres. Although the precipitation of cellulose carbamate in sulfuric acid is similar to the precipitation process in the viscose method, a completely different principle applies. Cellulose carbamate is stable under acidic conditions and therefore does not decompose into cellulose by precipitation, as in the viscose process. By bringing the alkali solution of the carbamate into contact with sulfuric acid, however, precipitation of the cellulose carbamate is effected and at the same time sodium sulphate is formed and sodium hydroxide is neutralized.
Når det ved utfelling av cellulosekarbamat fra en oppløs-ning av natriumhydroksyd, forsøkes benyttet lignende ut-fellingsoppløsninger som de som benyttes i viskoseprosessen, ble det funnet at tørrstoffinnholdet i den utfelte karbamatfiber holdt seg langt lavere enn i viskoseprosessen, hvilket er altfor lavt. Dette har den ytterligere konsekvens at det således fremstilte fiberprodukts innledende styrke ikke er tilstrekkelig til å tåle dé mekaniske påkjenninger som er innvolvert ved behandlingen av fiberen. Det lave tørr-stof f innholdet i fiberen innebærer også at i tørkefasen av fiberen må meget mer vann fordampes og mer energi forbrukes. When precipitation of cellulose carbamate from a solution of sodium hydroxide is attempted using similar precipitation solutions as those used in the viscose process, it was found that the dry matter content in the precipitated carbamate fiber remained far lower than in the viscose process, which is far too low. This has the further consequence that the initial strength of the thus produced fiber product is not sufficient to withstand the mechanical stresses involved in the processing of the fibre. The low dry matter content in the fiber also means that in the drying phase of the fiber much more water must be evaporated and more energy consumed.
Formålet med foreliggende oppfinnelse er en fremgangsmåte hvor det ved utfellingen av cellulosekarbamat oppnås et høyt nok tørrstoffinnhold. The purpose of the present invention is a method in which a sufficiently high dry matter content is achieved during the precipitation of cellulose carbamate.
Ifølge foreliggende oppfinnelse er det således tilveiebragt en fremgangsmåte for utfelling av cellulosekarbamat fra en vandig alkalioppløsning. av cellulosekarbamat, og denne fremgangsmåten er kjennetegnet ved at oppløsningen bringes i kontakt med en vandig oppløsning av svovelsyre som inneholder en eller flere av Al-, Mg-, Zn- og Ca-kationer, og som eventuelt ytterligere inneholder Na-kation. According to the present invention, there is thus provided a method for precipitating cellulose carbamate from an aqueous alkali solution. of cellulose carbamate, and this method is characterized by the fact that the solution is brought into contact with an aqueous solution of sulfuric acid which contains one or more of Al, Mg, Zn and Ca cations, and which possibly further contains Na cation.
Egnede kilder for tilførsel av Al-, Mg-, Ca- eller Zn-kationer er de tilsvarende sulfater, skjønt også andre salter, f.eks. klorider, kan benyttes. Det foreligger forskjeller mellom forskjellige kationer: det synes som om treverdige kationer er mer virkningsfulle enn to- Suitable sources for supplying Al, Mg, Ca or Zn cations are the corresponding sulphates, although also other salts, e.g. chlorides, can be used. There are differences between different cations: it seems that trivalent cations are more effective than divalent
verdige eller en-verdige kationer. En meget tilrådelig kationkilde er aluminiumsulfat, men resultater er også valence or monovalent cations. A highly recommended cation source is aluminum sulfate, but results are also
blitt oppnådd med magnesiumsulfat, natriumaluminiumsul- been obtained with magnesium sulfate, sodium aluminum sul-
fat - eller alun - og med sinksulfat. Kalsiumsulfat kan også anvendes selvom dets oppløselighet i fortynnet svovelsyre er temmelig lav. barrel - or alum - and with zinc sulphate. Calcium sulphate can also be used although its solubility in dilute sulfuric acid is rather low.
Som i viskoseprosessen er det likeledes mulig å regulere As in the viscose process, it is also possible to regulate
og styre utfellingsforholdene for cellulosekarbamat ved å endre prosessbetingelsene. Slike prosessvariable er f.eks. sammensetningen av utfellingsbadet, temperatur, tid, karba-matinnhold i oppløsningen, dens viskositet osv. Svovel-syreinnholdet påvirker f.eks. karbamat-utfellingshastig-heten, mens kationinnholdet først og fremst påvirker tørr-stof f innholdet i fiberen. Det riktige svovelinnholdet i fremgangsmåten ifølge oppfinnelsen varierer som regel mellom 2-20 vekt-% og mengden av Al-, Mg-, Ca- eller Zn-salt mellom 0,1-25 vekt-%. I en kontinuerlig prosess akkumuleres natriumsulfat i oppløsningen og utfellingsoppløsningen kan derfor regenereres som kjent innen teknikken ved tilsetning av stoffer som forbrukes under prosessen og fjerning av stoffer som akkumuleres i overskuddsmengder. I fremgangsmåten ifølge oppfinnelsen er det således mulig å and control the precipitation conditions for cellulose carbamate by changing the process conditions. Such process variables are e.g. the composition of the precipitation bath, temperature, time, carbamate content in the solution, its viscosity, etc. The sulfuric acid content affects e.g. the carbamate precipitation rate, while the cation content primarily affects the dry matter content of the fibre. The correct sulfur content in the method according to the invention usually varies between 2-20% by weight and the amount of Al, Mg, Ca or Zn salt between 0.1-25% by weight. In a continuous process, sodium sulfate accumulates in the solution and the precipitation solution can therefore be regenerated as known in the art by adding substances that are consumed during the process and removing substances that accumulate in excess amounts. In the method according to the invention, it is thus possible to
fjerne natriumsulfat f.eks. ved fordampning av vann og utfelling, og å tilsette svovelsyre og aluminiumsulfat eller et annet sulfat. Mengden av natriumsulfat holdes normalt mellom 3 og 30 vekt-%. remove sodium sulfate e.g. by evaporation of water and precipitation, and adding sulfuric acid and aluminum sulphate or another sulphate. The amount of sodium sulphate is normally kept between 3 and 30% by weight.
Ved fremgangsmåten ifølge oppfinnelsen kan både fibere og filmer fremstilles under anvendelse av konvensjonell .. apparaturer og prosesser i viskosemetoden. Når fibrer fremstilles, spinnes karbamatoppløsningen gjennom spinneåpninger inn i utfellingsbadet, og når filmer fremstilles, presses oppløsningen gjennom en spalteåpning for derved å dannes til en film. I fremgangsmåten ifølge oppfinnelsen inneholder natriumhydroksydoppløsningen av cellulosekarbamat 4-15 vekt-% cellulosekarbamat. En riktig viskositet for oppløsningen er som regel mellom 50 og 500 cP. With the method according to the invention, both fibers and films can be produced using conventional equipment and processes in the viscose method. When fibers are produced, the carbamate solution is spun through spinning apertures into the deposition bath, and when films are produced, the solution is pressed through a slit opening to thereby form a film. In the method according to the invention, the sodium hydroxide solution of cellulose carbamate contains 4-15% by weight of cellulose carbamate. A correct viscosity for the solution is usually between 50 and 500 cP.
Etter utfelling kan etterbehandlingen av fibrene eller filmene slik som vasketrinn, tørketrinn osv., utføres under anvendelse av metoder og apparatur som i seg selv er kjent innen teknikken og som ikke omfattes av foreliggende opp-finnelses ramme. After deposition, the finishing of the fibers or films, such as a washing step, drying step, etc., can be carried out using methods and apparatus which are themselves known in the art and which are not covered by the scope of the present invention.
I de medfølgende eksempler illustreres en anvendelse av oppfinnelsen ved spinning av cellulosekarbamatfibre, mens det er åpenbart at fremgangsmåten ifølge oppfinnelsen ikke er begrenset bare til utfelling av fibre, men er like egnet for fremstilling av filmlignende produkter eller andre produkttyper ved utfelling av cellulosekarbamat fra en alkalioppløsning. In the accompanying examples, an application of the invention is illustrated in the spinning of cellulose carbamate fibers, while it is obvious that the method according to the invention is not limited only to the precipitation of fibers, but is equally suitable for the production of film-like products or other product types by precipitation of cellulose carbamate from an alkali solution .
Eksempel 1 Example 1
Cellulosekarbamat ble fremstilt ved blanding av 430 g tørr-malt bleket furucellulose (DP 510) og 35 g Na2C03 i kald xylen i en glasskolbe med tilbakeløpskjøler. Xylenen ble oppvarmet til 139°C og 500 g granulært urea ble tilsatt. Oppvarming med omrøring ble fortsatt i 2 timer. Deretter ble xylenen avdestillert ved undertrykk og cellulosekarbamatproduktet ble vasket med vann. Nitrogeninnholdet i karbamatet var 3,6 vekt-% og DP var 365. Cellulose carbamate was prepared by mixing 430 g of dry-ground bleached pine cellulose (DP 510) and 35 g of Na 2 CO 3 in cold xylene in a glass flask with a reflux condenser. The xylene was heated to 139°C and 500 g of granular urea was added. Heating with stirring was continued for 2 hours. The xylene was then distilled off under reduced pressure and the cellulose carbamate product was washed with water. The nitrogen content of the carbamate was 3.6% by weight and the DP was 365.
En cellulosekarbamatoppløsning ble fremstilt ved oppløsning av cellulosekarbamat fremstilt på den måten som nettopp er beskrevet i en 10% NaOH-oppløsning. Karbamatinnholdet i opp-løsningen var 5,8% og kuleviskositeten 53 s. A cellulose carbamate solution was prepared by dissolving cellulose carbamate prepared in the manner just described in a 10% NaOH solution. The carbamate content in the solution was 5.8% and the ball viscosity 53 s.
Klumpverdien for oppløsningen ble bestemt ved metoden beskrevet i: H. Sihtola, Paperi ja Puu 44 (1962), nr. 5, The lump value of the solution was determined by the method described in: H. Sihtola, Paperi ja Puu 44 (1962), no. 5,
side 295-300. Klumpverdien for oppløsningen ble funnet å være 15 000. Oppløsningen ble presset inn i en svovelsyre-oppløsning gjennom en åpning med 10 0 hull med diameter 0,09 mm. pages 295-300. The lump value of the solution was found to be 15,000. The solution was pressed into a sulfuric acid solution through an orifice with 10 0 holes of diameter 0.09 mm.
Fibertråden fremstilt ved utfelling i svovelsyreoppløsningen ble løftet på en valse fra utfellingsoppløsningen. Tørr-stof f innholdet i fibrene ble bestemt på to måter. I et tilfelle ble fibertråden først tørket mellom trekkpapir. Deretter ble fibrene veiet, vasket med vann og på nytt veiet, og tørrstoffinnholdet ble beregnet. I det andre tilfellet ble fibrene ikke tørket mellom trekkpapir før den første veiingen. The fiber thread produced by precipitation in the sulfuric acid solution was lifted on a roller from the precipitation solution. The dry matter content of the fibers was determined in two ways. In one case, the fiber thread was first dried between tracing paper. The fibers were then weighed, washed with water and weighed again, and the dry matter content was calculated. In the second case, the fibers were not dried between blotting papers before the first weighing.
I tabell I angis sammensetningene for de benyttede utfell-ingsoppløsningene, utfellingstidene og de oppnådde tørrstoff-innhold. Table I shows the compositions for the precipitation solutions used, the precipitation times and the solids content obtained.
Dette eksempel viser at cellulosekarbamat utfelles selv This example shows that cellulose carbamate precipitates itself
i kun svovelsyreoppløsning, men at tørrstoffinnholdet forblir lavt. En utfellingsoppløsning inneholdende natriumsulfat i tillegg til svovelsyre oppfører seg på samme måte. Aluminiumsulfat forårsaker en vesentlig forbedring i tørrstoffinnholdet i fiberen. in only sulfuric acid solution, but that the dry matter content remains low. A precipitation solution containing sodium sulfate in addition to sulfuric acid behaves in the same way. Aluminum sulphate causes a significant improvement in the dry matter content of the fibre.
Eksempel 2 Example 2
Cellulosekarbamat ble fremstilt som følger: 430 g tørr-dispergert bleket sulfittcellulose (gran/furu) (DP 400) ble impregnert med en oppløsning inneholdende 3,6 1 flytende ammoniakk og 200 g urea, ved -45°C i 3 timer. Deretter fikk amoniakken fordampe ved romtemperatur i en 15 liters reaktor natten over. Reaktortemperaturen ble hevet til å være 135°C i 3 timer hvoretter cellulosekarbamatproduktet (med N-innhold 2,4%, DP 310) ble vasket med vann og oppløst i 10% NaOH-oppløsning. Karbamatinnholdet i oppløsningen var 6,5 vekt-% og klumptallet 13 000. Cellulose carbamate was prepared as follows: 430 g of dry-dispersed bleached sulphite cellulose (spruce/pine) (DP 400) was impregnated with a solution containing 3.6 L of liquid ammonia and 200 g of urea, at -45°C for 3 hours. The ammonia was then allowed to evaporate at room temperature in a 15 liter reactor overnight. The reactor temperature was raised to 135°C for 3 hours after which the cellulose carbamate product (with N content 2.4%, DP 310) was washed with water and dissolved in 10% NaOH solution. The carbamate content in the solution was 6.5% by weight and the lump number 13,000.
Utfellingsforsøk ble utført på den måte som er angitt i eksempel 1, men under anvendelse av sink- og magnesium-ioner. Resultatene er angitt i tabell II. Precipitation experiments were carried out in the manner indicated in example 1, but using zinc and magnesium ions. The results are shown in Table II.
Eksempel 3 Example 3
Cellulosekarbamat ble fremstilt som i eksempel 2 med unntagelse av at ureamengden var 300 g. DP-verdien for det således oppnådde cellulosekarbamat var 320 og nitrogeninnholdet 2,2%. Cellulose carbamate was prepared as in example 2 with the exception that the amount of urea was 300 g. The DP value for the cellulose carbamate thus obtained was 320 and the nitrogen content 2.2%.
En oppløsning ble fremstilt av cellulosekarbamatet som i eksempel 2. Karbamatinnholdet i oppløsningen var 6,5 vekt-% og klumpverdien var 1045. Resultatene fra ut-fellingsforsøkene er angitt i tabell III. A solution was prepared from the cellulose carbamate as in Example 2. The carbamate content in the solution was 6.5% by weight and the lump value was 1045. The results of the precipitation experiments are given in Table III.
Eksempel• 4 Example• 4
Cellulosekarbamat ble fremstilt som i eksempel 3 med den unntagelse at bleket sulfittcellulose (furu) ble benyttet som utgangsmateriale, idet DP-verdien var 380. Nitrogeninnholdet i karbamatet var 1,7% og dets DP-verdi 290. En NaOH-oppløsning ble fremstilt fra karbamatet som i eksempel 3 og klumpverdien ble funnet å være 1900. Utfellingsoppløs-ningene som ble benyttet er angitt i tabell IV. Utfell-ingstiden var 11 minutter. Cellulose carbamate was prepared as in example 3 with the exception that bleached sulphite cellulose (pine) was used as starting material, the DP value being 380. The nitrogen content of the carbamate was 1.7% and its DP value 290. A NaOH solution was prepared from the carbamate as in example 3 and the lump value was found to be 1900. The precipitation solutions that were used are indicated in table IV. The precipitation time was 11 minutes.
Claims (4)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
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FI814209A FI64603C (en) | 1981-12-30 | 1981-12-30 | EXTENSION OF CELLULOSE EXTENSION |
PCT/FI1982/000070 WO1983002279A1 (en) | 1981-12-30 | 1982-12-30 | Procedure for precipitating cellulose derivative |
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NO832928L NO832928L (en) | 1983-08-15 |
NO156529B true NO156529B (en) | 1987-06-29 |
NO156529C NO156529C (en) | 1987-10-07 |
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NO832928A NO156529C (en) | 1981-12-30 | 1983-08-15 | PROCEDURE FOR CELLULOSE CARBAMATE COLLECTION. |
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