NO154274B - PROCEDURE FOR CONNECTING LIGNOCELLULOSE. - Google Patents
PROCEDURE FOR CONNECTING LIGNOCELLULOSE. Download PDFInfo
- Publication number
- NO154274B NO154274B NO793738A NO793738A NO154274B NO 154274 B NO154274 B NO 154274B NO 793738 A NO793738 A NO 793738A NO 793738 A NO793738 A NO 793738A NO 154274 B NO154274 B NO 154274B
- Authority
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- Norway
- Prior art keywords
- lignin
- alcohol
- lignocellulose
- acid
- water
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims description 25
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 36
- 150000003839 salts Chemical class 0.000 claims description 24
- 229920005610 lignin Polymers 0.000 claims description 21
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 19
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 19
- 239000002253 acid Substances 0.000 claims description 11
- 238000009835 boiling Methods 0.000 claims description 11
- 239000000203 mixture Substances 0.000 claims description 10
- 230000029087 digestion Effects 0.000 claims description 9
- 229910052751 metal Inorganic materials 0.000 claims description 9
- 239000002184 metal Substances 0.000 claims description 9
- 235000000346 sugar Nutrition 0.000 claims description 9
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 claims description 8
- 239000000126 substance Substances 0.000 claims description 7
- 229910052500 inorganic mineral Inorganic materials 0.000 claims description 6
- 239000011707 mineral Substances 0.000 claims description 6
- 235000010755 mineral Nutrition 0.000 claims description 6
- 239000000843 powder Substances 0.000 claims description 5
- 229910052943 magnesium sulfate Inorganic materials 0.000 claims description 4
- 235000019341 magnesium sulphate Nutrition 0.000 claims description 4
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims description 3
- 229920003043 Cellulose fiber Polymers 0.000 claims description 3
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 3
- 229910002651 NO3 Inorganic materials 0.000 claims description 3
- 239000011575 calcium Substances 0.000 claims description 3
- 239000011777 magnesium Substances 0.000 claims description 3
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 claims description 2
- -1 aliphatic alcohols Chemical class 0.000 claims description 2
- 229910052791 calcium Inorganic materials 0.000 claims description 2
- 125000004432 carbon atom Chemical group C* 0.000 claims description 2
- 238000005119 centrifugation Methods 0.000 claims description 2
- 238000001704 evaporation Methods 0.000 claims description 2
- 230000008020 evaporation Effects 0.000 claims description 2
- 238000001914 filtration Methods 0.000 claims description 2
- 229910052749 magnesium Inorganic materials 0.000 claims description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims 1
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 claims 1
- TZCXTZWJZNENPQ-UHFFFAOYSA-L barium sulfate Inorganic materials [Ba+2].[O-]S([O-])(=O)=O TZCXTZWJZNENPQ-UHFFFAOYSA-L 0.000 claims 1
- 229910017604 nitric acid Inorganic materials 0.000 claims 1
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 14
- 239000000243 solution Substances 0.000 description 14
- 238000010411 cooking Methods 0.000 description 12
- 235000019441 ethanol Nutrition 0.000 description 10
- 229920002678 cellulose Polymers 0.000 description 9
- 239000001913 cellulose Substances 0.000 description 9
- 239000002023 wood Substances 0.000 description 9
- 241000218657 Picea Species 0.000 description 8
- 239000000835 fiber Substances 0.000 description 6
- 239000000463 material Substances 0.000 description 6
- 239000003054 catalyst Substances 0.000 description 5
- 239000007788 liquid Substances 0.000 description 5
- 229920002488 Hemicellulose Polymers 0.000 description 4
- 238000007792 addition Methods 0.000 description 4
- 239000001110 calcium chloride Substances 0.000 description 4
- 229910001628 calcium chloride Inorganic materials 0.000 description 4
- 239000003795 chemical substances by application Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 3
- 241000218631 Coniferophyta Species 0.000 description 3
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 description 3
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 3
- 241000183024 Populus tremula Species 0.000 description 3
- 229910052784 alkaline earth metal Inorganic materials 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 3
- 235000011148 calcium chloride Nutrition 0.000 description 3
- 239000002655 kraft paper Substances 0.000 description 3
- 239000012978 lignocellulosic material Substances 0.000 description 3
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L magnesium chloride Substances [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- 150000008163 sugars Chemical class 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- 229920001131 Pulp (paper) Polymers 0.000 description 2
- 230000002378 acidificating effect Effects 0.000 description 2
- 150000007513 acids Chemical class 0.000 description 2
- 150000001342 alkaline earth metals Chemical class 0.000 description 2
- 230000007062 hydrolysis Effects 0.000 description 2
- 238000006460 hydrolysis reaction Methods 0.000 description 2
- 229910001629 magnesium chloride Inorganic materials 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 description 2
- 150000007524 organic acids Chemical class 0.000 description 2
- 235000005985 organic acids Nutrition 0.000 description 2
- BDERNNFJNOPAEC-UHFFFAOYSA-N propan-1-ol Chemical compound CCCO BDERNNFJNOPAEC-UHFFFAOYSA-N 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 239000011122 softwood Substances 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 241000196324 Embryophyta Species 0.000 description 1
- 229920001503 Glucan Polymers 0.000 description 1
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 1
- 241001233242 Lontra Species 0.000 description 1
- 240000004808 Saccharomyces cerevisiae Species 0.000 description 1
- 238000007605 air drying Methods 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 150000001450 anions Chemical class 0.000 description 1
- 238000001479 atomic absorption spectroscopy Methods 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000005341 cation exchange Methods 0.000 description 1
- 150000001768 cations Chemical class 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 150000001805 chlorine compounds Chemical class 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 239000000539 dimer Substances 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- DQYBDCGIPTYXML-UHFFFAOYSA-N ethoxyethane;hydrate Chemical compound O.CCOCC DQYBDCGIPTYXML-UHFFFAOYSA-N 0.000 description 1
- 238000000855 fermentation Methods 0.000 description 1
- 230000004151 fermentation Effects 0.000 description 1
- 238000005227 gel permeation chromatography Methods 0.000 description 1
- 239000008103 glucose Substances 0.000 description 1
- 230000009931 harmful effect Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000004128 high performance liquid chromatography Methods 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 230000003301 hydrolyzing effect Effects 0.000 description 1
- GPRLSGONYQIRFK-UHFFFAOYSA-N hydron Chemical compound [H+] GPRLSGONYQIRFK-UHFFFAOYSA-N 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 150000007522 mineralic acids Chemical class 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 239000003791 organic solvent mixture Substances 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 229920001282 polysaccharide Polymers 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 239000012266 salt solution Substances 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 235000021309 simple sugar Nutrition 0.000 description 1
- 239000011877 solvent mixture Substances 0.000 description 1
- 238000003797 solvolysis reaction Methods 0.000 description 1
- 241000894007 species Species 0.000 description 1
- 238000001694 spray drying Methods 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 238000007655 standard test method Methods 0.000 description 1
- 230000008961 swelling Effects 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 229920001221 xylan Polymers 0.000 description 1
- 150000004823 xylans Chemical class 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
- D21C3/00—Pulping cellulose-containing materials
- D21C3/20—Pulping cellulose-containing materials with organic solvents or in solvent environment
Description
Foreliggende oppfinnelse vedrører en fremgangsmåte for oppslutning av lignocellulose hvor lignocellulose kokes med en blanding av vann og 1 til 4 volumdeler av en lavmolekylær alkohol med 3 eller færre C-atomer pr. volumdel vann, med et metallsalt, samt eventuelt en mindre mengde av et surt reagerende stoff høyst 2 timer ved 130 til 210°C, hvor det pr. vektdel lignocellulose anvendes minst 4 vektdeler kokeoppløsning, hvor de cellulosefibrene som frigjøres adskilles fra oppløsningen, alkoholen avdampes, og lignin og sukker utvinnes fra avluten. The present invention relates to a method for digestion of lignocellulose where lignocellulose is boiled with a mixture of water and 1 to 4 parts by volume of a low molecular weight alcohol with 3 or fewer C atoms per part by volume of water, with a metal salt, as well as possibly a smaller amount of an acid-reactive substance for no more than 2 hours at 130 to 210°C, where per part by weight of lignocellulose, at least 4 parts by weight of boiling solution are used, where the cellulose fibers that are released are separated from the solution, the alcohol is evaporated, and lignin and sugar are extracted from the effluent.
Organosolv-fremgangsmåten er kjent fra det mot-holdte patentskrift GB-PS 357821, US-PS 3585104, DE-AS 2644155 og Kleinert's artikkel i "Das Papier" 30 (1976), hefte 10A, side V 18 til V 24. Denne fremgangsmåten har, fremfor tradisjonelle fremgangsmåter til utvinning av ligno-cellulosematerialer, den fordel at den kan gjennomføres uten betydelig miljøforurensning; fordi den, bortsett fra små mengder sure og basiske substanser, foruten vann, kun innbefatter alkohol som kan gjenvinnes og resirkuleres. Prosessen har imidlertid også ulemper. F.eks. angis, i nevnte DE-AS 2644155, at oppslutningsmidlet som kontinuerlig tilføres i motstrøm må innstilles på en pH-verdi over 8 ved tilsats av basisk stoff, slik at pH-verdien i det brukte oppslutningsmiddel blir liggende mellom 4 og 7, og at denne pll-verdien ikke synker vesentlig under 4, hvilket fortrinns-vis skjer ved tilsats av ammoniakk. Som grunn for dette angis at avspaltningen av organiske syrer fra lignocellu-losematerialet riktignok øker hastigheten for delignifiseringen, men vil samtidig, ved det videre forløp av prosessen, angripe den cellulosen som frigjøres. The Organosolv process is known from the opposed patents GB-PS 357821, US-PS 3585104, DE-AS 2644155 and Kleinert's article in "Das Papier" 30 (1976), booklet 10A, pages V 18 to V 24. This process has, over traditional methods for extracting ligno-cellulosic materials, the advantage that it can be carried out without significant environmental pollution; because, apart from small amounts of acidic and basic substances, besides water, it only contains alcohol which can be recovered and recycled. However, the process also has disadvantages. E.g. it is stated, in the aforementioned DE-AS 2644155, that the digesting agent which is continuously supplied in countercurrent must be set to a pH value above 8 by the addition of a basic substance, so that the pH value in the digesting agent used is between 4 and 7, and that this The pll value does not drop significantly below 4, which preferably happens when ammonia is added. The reason for this is that the release of organic acids from the lignocellulosic material does indeed increase the speed of delignification, but will at the same time, during the further course of the process, attack the cellulose that is released.
Hydrogenionenes akselererende virkning på oppslutningsprosessen er inngående beskrevet i Kleinert's artikkel i "Angew. Chemie" 4_4 (1931) side 788 til 791, se spesielt spalte 1 side 790, og er anskueliggjort ved den tilhørende figur 4. Fremgangsmåten må følgelig gjennom-føres i et pH-område hvor delignifiseringen forløper relativt langsomt. The accelerating effect of the hydrogen ions on the digestion process is described in detail in Kleinert's article in "Angew. Chemie" 4_4 (1931) pages 788 to 791, see especially column 1 page 790, and is visualized by the associated figure 4. The procedure must therefore be carried out in a pH range where delignification proceeds relatively slowly.
Når det gjelder hydrogenion-konsentrasjonens virkning på den diskontinuerlige oppslutningsprosessen for lignocellulose i alkohol-vann-blandinger, beskrives i GP-PS 357821, side 1, linje 88 til side 2, linje 18, tilsats av små mengder (0,1% med hensyn på oppslutningsmidlet) av sure eller basiske substanser, som f.eks. uorganiske eller organiske syrer og deres surt reagerende salter, Regarding the effect of the hydrogen ion concentration on the discontinuous digestion process for lignocellulose in alcohol-water mixtures, GP-PS 357821, page 1, line 88 to page 2, line 18, describes the addition of small amounts (0.1% with respect on the dissolving agent) of acidic or basic substances, such as e.g. inorganic or organic acids and their acid-reactive salts,
eller som basiske substanser, oksyder, hydroksyder eller karbonater av alkali- eller jordalkalimetaller. Sammenlignet med dette adskiller fremgangsmåten ifølge oppfinnelsen seg ved det målrettede valg av salter i form av støkio-metrisk nøytrale salter av bestemte sterke mineralsyrer og bestemte jordalkalimetaller. or as basic substances, oxides, hydroxides or carbonates of alkali or alkaline earth metals. Compared to this, the method according to the invention differs by the targeted choice of salts in the form of stoichiometrically neutral salts of certain strong mineral acids and certain alkaline earth metals.
En ytterligere forskjell fra kjente, kontinuer-lige fremgangsmåter ligger i at ved avdampning av alkoholen fra den brukte oppslutningsløsningen i disse fremgangsmåtene, skiller det oppløste ligninstoff seg ut som en mørkebrun, tilsynelatende smeltet, fase (US-PS 3585104, spalte 8, linje 54 til 56; "Das Papier" nevnt ovenfor, side V, 21 høyere spalte, linje 6 til 2 nedenfra). På denne formen lar ligninet seg vanskelig fjerne fra apparaturen og kan vanskelig anvendes teknisk. A further difference from known, continuous processes lies in the fact that when the alcohol is evaporated from the digestion solution used in these processes, the dissolved lignin material stands out as a dark brown, apparently melted, phase (US-PS 3585104, column 8, line 54 to 56; "Das Papier" mentioned above, page V, 21 higher column, lines 6 to 2 from bottom). In this form, the lignin is difficult to remove from the equipment and can hardly be used technically.
Til grunn for foreliggende oppfinnelse ligger den oppgave å utvikle en fremgangsmåte som fremgangsmåtene som er omtalt i de ovenfor angitte Kleinert-referenasene, hvor man på vesentlig kortere tid enn ved disse kan oppnå en masse med god ligninfrihet (lavt kappa-tall) fra en cellulose med høy polymerisasjonsgrad (DP), og hvor dessuten det ligninet som finnes i den forbrukte oppslutningsoppløs-ningen kan utvinnes som pulver. The present invention is based on the task of developing a method such as the methods described in the above-mentioned Kleinert references, where a pulp with good lignin-freeness (low kappa number) can be obtained from a cellulose in a significantly shorter time than with these with a high degree of polymerization (DP), and where, moreover, the lignin found in the spent digestion solution can be extracted as powder.
Gjenstanden for foreliggende oppfinnelse er The object of the present invention is
den i patentkravene angitte fremgangsmåten. the method specified in the patent claims.
Ved tilsats av ett eller flere av de ifølge patentkravene anvendte jordalkalisaltene til kokeoppløs-ningen ved den kjente alkohol/vann-lignocelluloseoppslut-ningen, oppnås en vesentlig forkortelse av oppslutnings-tiden, og videre utfelles det i kokeoppløsningen oppløste ligninet ved ekspansjonsavdampning av alkoholen som pulver-formig bunnfall og kan utvinnes som pulver ved enkel filtrering eller sentrifugering. By adding one or more of the alkaline earth salts used according to the patent claims to the cooking solution in the known alcohol/water-lignocellulose digestion, a significant shortening of the digestion time is achieved, and further the lignin dissolved in the cooking solution is precipitated by expansion evaporation of the alcohol as a powder -shaped precipitate and can be recovered as a powder by simple filtration or centrifugation.
Fremgangsmåten ifølge oppfinnelsen er spesielt effektiv når saltet er magnesium- eller kalsiumklorid eller The method according to the invention is particularly effective when the salt is magnesium or calcium chloride or
-nitrat eller magnesiumsulfat ved en molarkonsentrasjon mellom 0,02 og 0,05 og når alkoholen er metanol og volumfor-holdet mellom metanol og vann i oppløsningsmiddelblandingen er 60:40 til 80:20, og kokingen utføres ved en temperatur mellom 190 og 200°C. Når nåletrær, som f.eks. gran, kokes, oppnås en masse som fremdeles inneholder betydelige mengder hemicelluloser, men som likevel har et lavere resterende lignininnhold, mens DP-verdien er høyere enn ved de fleste massene som kan oppnås ved kraft-prosessen. Ved en koketid på bare 30 til 45 minutter, oppnås en masse med et kappa--3 -nitrate or magnesium sulfate at a molar concentration between 0.02 and 0.05 and when the alcohol is methanol and the volume ratio between methanol and water in the solvent mixture is 60:40 to 80:20, and the boiling is carried out at a temperature between 190 and 200° C. When conifers, such as spruce, is boiled, a pulp is obtained which still contains significant amounts of hemicelluloses, but which nevertheless has a lower residual lignin content, while the DP value is higher than with most of the pulps which can be obtained by the kraft process. With a cooking time of only 30 to 45 minutes, a mass with a kappa--3 is obtained
tall pa 33, en TAPPI-viskositet ved 0,5 g pa 20 Pas Det kokte flismateriale separeres i enkeltfibre ved enkel røring, og den resulterende massen kan lett blekes fra en lyshet på 50% GE, som den oppviser etter kokingen, til den ønskede lysheten på 80%, og er i dette henseende overlegen granmassene som fremstilles ved kraft-prosessen med sammen-lignbart resterende lignininnhold, som oppviser en lavere utgangslyshet på typisk 35% GE. number of 33, a TAPPI viscosity at 0.5 g of 20 Pas The cooked chip material is separated into individual fibers by simple stirring, and the resulting mass can be easily bleached from a lightness of 50% GE, which it exhibits after cooking, to the desired lightness of 80%, and in this respect is superior to the spruce pulps produced by the kraft process with comparable residual lignin content, which show a lower initial lightness of typically 35% GE.
Sukkeroppløsningen som oppnås etter utskillelse av ligninet fra den forbrukte oppslutningsoppløsningen er rik på xylan og andre hemicelluloser og inneholder bare små mengder glukan. De fleste sukkere forekommer som dimerer og oligomerer med lav molekylvekt som lett kan nedbrytes til enkle sukkere ved en sekundær hydrolyse i nesten kvantitativt utbytte. Det faktum at sukkerene forekommer som sukkerpolymerer med lav molekylvekt beskytter dem mot en dehydratisering under høytemperaturkokingen, slik at man oppnår et relativt stort utbytte av oppløst sukker. The sugar solution obtained after separation of the lignin from the spent digestion solution is rich in xylan and other hemicelluloses and contains only small amounts of glucan. Most sugars occur as low molecular weight dimers and oligomers which can be easily broken down into simple sugars by secondary hydrolysis in almost quantitative yield. The fact that the sugars occur as low molecular weight sugar polymers protects them from dehydration during the high-temperature cooking, so that a relatively large yield of dissolved sugar is achieved.
Det utfelte ligninet har en molekylvekt (bestemt ved gelgjennomtrengningskromatografi og høytrykks-væske-kromatografi) mellom 300 og 12000, med en beregnet midlere molekylvekt omkring 3000. Det kan oppløses i aceton eller et annet ligninoppløsningsmiddel og utfelles på nytt ved tilsats av vann eller dietyleter, benzol, n-heksan eller diklormetan. Ved spraytørking fra en acetonoppløsning ved under 65°C, oppnås ligninet vanligvis i form av et fritt flytende pulver av lys farge. The precipitated lignin has a molecular weight (determined by gel permeation chromatography and high-pressure liquid chromatography) between 300 and 12,000, with a calculated average molecular weight around 3,000. It can be dissolved in acetone or another lignin solvent and re-precipitated by the addition of water or diethyl ether, benzene, n-hexane or dichloromethane. By spray-drying from an acetone solution at below 65°C, the lignin is usually obtained in the form of a free-flowing, light-coloured powder.
Det fullstendig kokte flismateriale lar seg lett skille i frie fibrer ved oppslemming i et godt ligninopp-løsningsmiddel hvorved store mengder lignin fjernes fra fibrene. Vanligvis er enkel vask med varm metanol/vann eller med aceton tilstrekkelig til å fjerne hovedmengden av det oppløste ligninet som befinner seg i fibrene. Etterfølgende vasking med vann har ingen skadelig virkning på blekbar-heten av fibrene. Kjennetegnende for fremgangsmåten ifølge oppfinnelsen er det også at den "frihet"-graden som normalt er ønsket i papirmasse, kan oppnås med betydelig mindre energiforbruk i malerhollenderen. Den opprinnelige "freeness" på 750 CFS, som oppnås med granmasser, krever bare 4000 omdreininger i en PFI-malerhollender for oppnåelse av en "freeness" på 300 sammenlignet med kraftmasser med den samme innledende "freeness" som krever mellom 7000 og 9000 omdreininger for å oppnå samme "freness", typisk 300 CFS. The fully cooked chip material can be easily separated into free fibers by slurrying in a good lignin solvent, whereby large amounts of lignin are removed from the fibers. Usually, simple washing with hot methanol/water or with acetone is sufficient to remove the bulk of the dissolved lignin present in the fibers. Subsequent washing with water has no harmful effect on the bleachability of the fibres. A characteristic of the method according to the invention is also that the degree of "freedom" normally desired in paper pulp can be achieved with significantly less energy consumption in the painter's Dutchman. The initial "freeness" of 750 CFS achieved with spruce pulps requires only 4000 revolutions in a PFI painter dutch to achieve a "freeness" of 300 compared to kraft pulps of the same initial "freeness" which require between 7000 and 9000 revolutions to to achieve the same "freness", typically 300 CFS.
De følgende eksemplene anskueliggjør foreliggende oppfinnelse. The following examples illustrate the present invention.
Eksempel 1 Example 1
Det ble utført et studium av viskositeten A study of the viscosity was carried out
av cellulosemassen under anvendelse av 0,16 molar konsentrasjon CaCl2 i 30:70 blandinger av vann med metanol, etanol, eller n-propanol. Kokingene ble foretatt i laboratoriemålestokk i en rustfri trykk-beholder av stål med en høyde på ca. 20 cm og diameter på 8 cm. Lufttørr grantreflis med et fuktighetsinnhold på 8% ble anbragt i kokeren i 10 g porsjoner sammen med 10 g av på forhånd fremstilt kokeoppløsning. Beholderne i forseglet tilstand ble oppvarmet til 200°C i et oljebad og holdt ved koke-temperatur i et bestemt tidsrom. Koketiden ble valgt slik at man fikk en fri masse etter oppslemming av den kokte flis i 500 ml aceton og omrøring av oppløsningen ved under of the cellulose pulp using 0.16 molar concentration CaCl2 in 30:70 mixtures of water with methanol, ethanol, or n-propanol. The boilings were carried out on a laboratory scale in a stainless steel pressure vessel with a height of approx. 20 cm and diameter of 8 cm. Air-dry spruce chips with a moisture content of 8% were placed in the cooker in 10 g portions together with 10 g of previously prepared cooking solution. The containers in the sealed state were heated to 200°C in an oil bath and kept at boiling temperature for a certain period of time. The cooking time was chosen so that a free mass was obtained after slurping the cooked chips in 500 ml of acetone and stirring the solution at
800 omdr./minutt. Ved slutten av kokeperioden ble beholderne avkjølt og væsken dekantert. Massen ble vasket med aceton fulgt av vann og lufttørket inntil konstant vekt var opp-nådd. Prøver ble tatt for bestemmelse av Kappa-tall og viskositet, hvoretter det endelige fuktighetsinnhold i den resterende masse ble bestemt slik at man kunne beregne masseutbyttet. For alle analyser ble det benyttet TAPPI-standard testmetoder. Alle data fra disse kokeserier er angitt i tabell I. Dataene viser tydelig den overlegne selektivitet hos metanol som delignifiseringsmiddel, hvilket fremgår ved den høye viskositeten hos den isolerte cellu-losemasse. 800 rpm. At the end of the boiling period, the containers were cooled and the liquid decanted. The mass was washed with acetone followed by water and air dried until constant weight was reached. Samples were taken to determine the Kappa number and viscosity, after which the final moisture content in the remaining mass was determined so that the mass yield could be calculated. For all analyses, TAPPI standard test methods were used. All data from these cooking series are given in Table I. The data clearly show the superior selectivity of methanol as a delignifier, which is evident from the high viscosity of the isolated cellulose pulp.
Eksempel 2 Example 2
Prosessen viser en høy toleranse overfor store variasjoner i den molare konsentrasjonen av metallsaltet under ellers konstante kokebetingelser. Lovved kan generelt kokes med lavere saltkonsentrasjoner av hvilke som helst av de foretrukne saltkatalysatorer, The process shows a high tolerance to large variations in the molar concentration of the metal salt under otherwise constant cooking conditions. Lovwood can generally be cooked with lower salt concentrations of any of the preferred salt catalysts,
enn nåletre; f.eks. koker ospetre med kalsium- eller magnesiumklorid eller -nitrat på mindre enn 30 min- than softwood; e.g. boil aspen wood with calcium or magnesium chloride or nitrate in less than 30 min-
utter ved saltkonsentrasjoner på 0,025 - 0,10 molar, otter at salt concentrations of 0.025 - 0.10 molar,
mens det derimot med magnesiumsulfat med samme konsentrasjon trengs 45 minutter. Nåletrær, slik som gran, whereas, on the other hand, with magnesium sulphate of the same concentration, 45 minutes are needed. Conifers, such as spruce,
vil vanligvis kreve en hoyere saltkonsentrasjon på will usually require a higher salt concentration of
mellom 0,05 og 0,20 molar, og i visse tilfeller kan forbedret fiberseparering oppnås med konsentrasjoner i nærheten av 0,5 molar eller hoyere. De foretrukne saltene er kloridene av magnesium og kalsium, som er billigst, samtidig som de tolereres godt i fermenter-ingsprosesser som den vandige sukkerresten kan tilsettes til for å omdanne sukrene til etylalkohol, gjær eller andre fermenterbare produkter. Magnesiumsulfat har begrenset opploselighet i alkoholer og den saltkonsentrasjon som kan oppnås i opplosning kan således ofte være begrenset. For å kompensere for den lavere saltkonsentrasjon av MgSO^ er det nbdvendig med koketider i over-kant av de som anses for aksepterbare. between 0.05 and 0.20 molar, and in certain cases improved fiber separation can be achieved with concentrations near 0.5 molar or higher. The preferred salts are the chlorides of magnesium and calcium, which are the cheapest, while being well tolerated in fermentation processes to which the aqueous sugar residue can be added to convert the sugars into ethyl alcohol, yeast or other fermentable products. Magnesium sulphate has limited solubility in alcohols and the salt concentration that can be achieved in solution can thus often be limited. To compensate for the lower salt concentration of MgSO^, boiling times in excess of those considered acceptable are necessary.
Nedenstående tabell II viser representative data for masseutbytte og egenskaper for en lbvvedtype, nemlig osp, og for en nåletretype, nemlig gran, kokt med vandig metanol ved 200°C med et konstant tre:væske-forhold på 1:10 (vann:metanolforholdet er 30:70). Table II below shows representative data for mass yield and properties for a type of lbvwood, namely aspen, and for a type of softwood, namely spruce, boiled with aqueous methanol at 200°C with a constant wood:liquid ratio of 1:10 (the water:methanol ratio is 30:70).
I tabell II ovenfor er DP-verdiene avledet fra TAPPI-standard viskositetsmålinger og bruk av nomo-gram utgitt av Rydholm på side 1120. In Table II above, the DP values are derived from TAPPI standard viscosity measurements and using the nomo-gram published by Rydholm on page 1120.
Eksempel 3 Example 3
Det ble foretatt ytterligere kokinger med tretyper og væskemengder som angitt i foregående eksempel. Væsken bestod av 70:30-blanding av vann og metanol inneholdende 0,10 mol CaC^ som kata-lysator. Både koketiden og temperaturen ble variert som angitt i tabell III. Further boilings were carried out with types of wood and amounts of liquid as stated in the previous example. The liquid consisted of a 70:30 mixture of water and methanol containing 0.10 mol CaC 2 as catalyst. Both the cooking time and the temperature were varied as indicated in Table III.
På grunn av at hvert lignocellulosemateriale representerer en forskjellig sammensetning og egenskap for sin lignin-karbohydrat-matrise slik det forekommer i naturlig dyrkede plantematerialer, vil utforelsen av oppfinnelsen nbdvendigvis kreve en viss forsøksvirk-somhet med et gitt materiale for oppnåelse av de optimale masseegenskaper. En viss rettesnor kan oppnås fra tabell IV som inneholder masseanalyser for 7 for-skjellige arter hvorav alle ga masser av hby kvalitet. Massene ble fremstilt under de ovenfor beskrevne betingelser. Det skal forstås at disse betingelser illu-strerer en god utfbrelse av oppfinnelsen snarere enn optimale betingelser. Tabellen inkluderer lyshetsark-'egenskaper av interesse etter at massene ble malt til 300 Canadian Standard Freeness, idet arkforsøkene ble utfort ifblge TAPPI-standarder. Massene ble bare behand-let med en acetonvask for å utvaske det opploste lignin og suspendert i vann for siling og dannelse av lys-hetsark. Due to the fact that each lignocellulosic material represents a different composition and property for its lignin-carbohydrate matrix as it occurs in naturally grown plant materials, the implementation of the invention will necessarily require a certain amount of experimental work with a given material to achieve the optimal mass properties. A certain guideline can be obtained from table IV, which contains mass analyzes for 7 different species, all of which gave masses of hby quality. The masses were prepared under the conditions described above. It should be understood that these conditions illustrate a good embodiment of the invention rather than optimal conditions. The table includes lightness sheet properties of interest after the pulps were milled to 300 Canadian Standard Freeness, the sheet tests being performed according to TAPPI standards. The pulps were simply treated with an acetone wash to wash out the dissolved lignin and suspended in water for screening and light sheet formation.
En sammenfattende analyse for sukkeret, lignin og tremasse ble utfort for osp- og grankokingene angitt i tabell IV, og er presentert i nedenstående tabell V. A summary analysis for the sugar, lignin and wood pulp was carried out for the aspen and spruce cookings indicated in table IV, and is presented in table V below.
Det hoye glukoseinnhold i massene indikerer liten, hvis i det hele tatt noen, nedbrytning av tre-cellulosen. The high glucose content in the pulps indicates little, if any, breakdown of the wood cellulose.
Eksempel 4 Example 4
Siden det ble antatt at saltene deltok i en slags kationutvekslingsreaksjon med treet, ble det for-ventet at noe av saltet ville bli bibeholdt i masse-fibrene. Av denne grunn ble det fremstilt masser ifolge eksempel III og disse ble kokt i et sterkt oksyderende middel, fulgt av fortynning med avmineralisert vann. Since it was assumed that the salts participated in some kind of cation exchange reaction with the wood, it was expected that some of the salt would be retained in the pulp fibers. For this reason, masses were prepared according to example III and these were boiled in a strong oxidizing agent, followed by dilution with demineralized water.
De resulterende opplbsninger ble deretter analysert The resulting solutions were then analyzed
for Ca<++> og Mg<++> ved atom-absorbsjonsspektrometri. De oppnådde data er angitt i tabell VI. for Ca<++> and Mg<++> by atomic absorption spectrometry. The data obtained are set out in Table VI.
Alle kokingene ble foretatt med 70:30 metanol: vann inneholdende 0,05 M MgCl2 eller CaCl2, idet temperaturen ble bibeholdt i 30 minutter. Massene ble vasket én gang med aceton og med to porsjoner 500 ml destillert vann for lufttorking og analyse. All boilings were carried out with 70:30 methanol:water containing 0.05 M MgCl 2 or CaCl 2 , maintaining the temperature for 30 minutes. The pulps were washed once with acetone and with two portions of 500 ml distilled water for air drying and analysis.
Det går klart frem fra tabell VI at massene inneholdt langt mindre kationer enn det som opprinnelig var tilstede i de respektive trematerialer. It is clear from Table VI that the pulps contained far fewer cations than were originally present in the respective wood materials.
Eksempel 5 Example 5
Det er kjent at man for hurtig bulk-delignifi-sering i syrekatalyserte, vandige organiske opplbsnings-middel-blandinger trenger relativt store innledende proton-konsentrasjoner for å bevirke hurtig delignifiser-ing. De angitte metallsalt-katalysatorer synes å mangle evnen til in situ-avgivelse av slike hoye proton-konsentrasjoner; i gjennomsnitt ble et pH-fall fra 5,8 It is known that for rapid bulk delignification in acid-catalyzed, aqueous organic solvent mixtures, relatively large initial proton concentrations are needed to effect rapid delignification. The specified metal salt catalysts seem to lack the ability to in situ release such high proton concentrations; on average, the pH dropped from 5.8
for 70:30 metanol:vann-blandinger inneholdende 0,05 for 70:30 methanol:water mixtures containing 0.05
mol CaCl2 til 4,2, bare observert når kokeopplosningen ble tilsatt til treflisen. Utvikling av slik svak syre-karakter i saltopplbsninger når de tilsettes til tre-flis er velkjent fra litteraturen. Enkelte ganger, spesielt med gymnosperm-arter, kan delignifiserings-hastigheten være for langsom og ikke selektiv nok slik at masser med lavt resterende lignininnhold er vanskelige å fremstille. I slike tilfeller ble det funnet at den innledende proton-konsentrasjon effektivt kan forbkes med små konsentrasjoner av mineralsyre, vanligvis av samme anion-type som man finner i metallsaltet. Slike syre-tilsetninger fremmer vanligvis bulk-delignifiseringen og hydrolysen av hemicellulosene ved et tidspunkt når cellulosen fremdeles er godt beskyttet fra protonene ved ligninbelegget siden dens opprinnelige strukturelle cellulose-omgivelse er mindre tilgjengelig for syrer når svelling ved hjelp av opplbsningsmidler er begrenset av lignin-hemicellulose-grunnmassen (eller -matrisen). Funksjonen og effektene til metallsalt-katalysatorene forblir uforandret i forhold til det som erfares i fra-vær av mineralsyren, dvs. metallsaltet tjener både som proton-utviklende middel samt gir viktig beskyttelse til cellulosen spesielt ved de senere koketrinn mot den umid-delbart fblgende hydrolytiske solvolyse. Bevis for en slik synergistisk effekt angis i tabell VII. De hoyere syrekonsentrasjoner finnes å være de mest effektive når det gjelder reduksjon av resterende lignin i massen. Dette oppnås på bekostning av en svak reduksjon i masseutbyttet uten betydelig fall i celluloseviskositeten. mol CaCl2 to 4.2, only observed when the boiling solution was added to the wood chips. Development of such a weak acid character in salt solutions when they are added to wood chips is well known from the literature. Sometimes, especially with gymnosperm species, the delignification rate can be too slow and not selective enough so that pulps with low residual lignin content are difficult to produce. In such cases, it was found that the initial proton concentration can be effectively neutralized with small concentrations of mineral acid, usually of the same anion type as found in the metal salt. Such acid additions usually promote the bulk delignification and hydrolysis of the hemicelluloses at a time when the cellulose is still well protected from the protons by the lignin coating since its native structural cellulose environment is less accessible to acids when solvent swelling is limited by the lignin-hemicellulose - the base mass (or matrix). The function and effects of the metal salt catalysts remain unchanged in relation to what is experienced in the absence of the mineral acid, i.e. the metal salt serves both as a proton-developing agent and provides important protection to the cellulose, especially in the later cooking stages against the immediately following hydrolytic solvolysis. Evidence for such a synergistic effect is given in Table VII. The higher acid concentrations are found to be the most effective when it comes to reducing residual lignin in the pulp. This is achieved at the expense of a slight reduction in the mass yield without a significant drop in the cellulose viscosity.
Lufttbrket grantreflis ble således kokt med et tre:væske-forhold på 1:10 med 70:30-blanding av metanol: vann tilsatt den angitte mengde syre/saltkatalysator. Temperaturen var 200°C og oppvarmingstiden, inkludert i den noterte tid, var 7 minutter for hver koking. Air-dried spruce chips were thus boiled with a wood:liquid ratio of 1:10 with a 70:30 mixture of methanol:water with the indicated amount of acid/salt catalyst added. The temperature was 200°C and the heating time, included in the noted time, was 7 minutes for each boil.
Claims (5)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
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CA316,951A CA1131415A (en) | 1978-11-27 | 1978-11-27 | Pulping of lignocellulose with aqueous methanol/ catalyst mixture |
DE2920731A DE2920731C2 (en) | 1978-11-27 | 1979-05-22 | Lignocellulose digestion process with a mixture of water and low molecular weight aliphatic alcohol and metal salt |
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NO793738L NO793738L (en) | 1980-05-28 |
NO154274B true NO154274B (en) | 1986-05-12 |
NO154274C NO154274C (en) | 1986-08-20 |
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NO793738A NO154274C (en) | 1978-11-27 | 1979-11-19 | PROCEDURE FOR CONNECTING LIGNOCELLULOSE. |
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AU (1) | AU528703B2 (en) |
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DD (1) | DD147259A5 (en) |
ES (1) | ES486267A1 (en) |
FI (1) | FI69129C (en) |
FR (1) | FR2442297A1 (en) |
GB (1) | GB2040332B (en) |
NO (1) | NO154274C (en) |
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US4594130A (en) * | 1978-11-27 | 1986-06-10 | Chang Pei Ching | Pulping of lignocellulose with aqueous alcohol and alkaline earth metal salt catalyst |
CA1275286C (en) * | 1986-05-29 | 1990-10-16 | Edward A. Delong | Method for extracting the chemical components from dissociated lignocellulosic material |
NZ579757A (en) * | 2007-06-20 | 2012-03-30 | Nagarjuna Energy Private Ltd | A single step process for separating biomass components |
AU2015286229B2 (en) * | 2014-07-10 | 2018-11-08 | Leaf Sciences Pty Ltd | Methods for treating lignocellulosic material |
US11332768B2 (en) | 2014-07-10 | 2022-05-17 | Leaf Sciences Pty Ltd | Methods for hydrolysing lignocellulosic material |
CN114645479B (en) * | 2020-12-19 | 2023-07-25 | 山东洲星天然物提取智能设备有限公司 | Preparation method of paper pulp |
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FI69129C (en) | 1985-12-10 |
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PT70475A (en) | 1979-12-01 |
AU5305679A (en) | 1981-06-04 |
RO77556A (en) | 1982-07-06 |
AU528703B2 (en) | 1983-05-12 |
AT372991B (en) | 1983-12-12 |
GB2040332B (en) | 1983-09-07 |
DD147259A5 (en) | 1981-03-25 |
BR7907651A (en) | 1980-08-26 |
NO793738L (en) | 1980-05-28 |
YU282279A (en) | 1982-10-31 |
FR2442297B1 (en) | 1983-05-13 |
PH16526A (en) | 1983-11-10 |
PL219837A1 (en) | 1980-12-15 |
ATA726179A (en) | 1983-04-15 |
NO154274C (en) | 1986-08-20 |
YU41897B (en) | 1988-02-29 |
ES486267A1 (en) | 1980-05-16 |
FI793678A (en) | 1980-05-28 |
PL131834B1 (en) | 1985-01-31 |
GB2040332A (en) | 1980-08-28 |
SE7909674L (en) | 1980-05-28 |
AR223198A1 (en) | 1981-07-31 |
SE436899B (en) | 1985-01-28 |
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