CA1181397A - Process for obtaining water-soluble saccharides from cellulose-containing material - Google Patents
Process for obtaining water-soluble saccharides from cellulose-containing materialInfo
- Publication number
- CA1181397A CA1181397A CA000389579A CA389579A CA1181397A CA 1181397 A CA1181397 A CA 1181397A CA 000389579 A CA000389579 A CA 000389579A CA 389579 A CA389579 A CA 389579A CA 1181397 A CA1181397 A CA 1181397A
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- CA
- Canada
- Prior art keywords
- wood
- cellolignin
- hydrogen fluoride
- cellulose
- containing material
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C13—SUGAR INDUSTRY
- C13K—SACCHARIDES OBTAINED FROM NATURAL SOURCES OR BY HYDROLYSIS OF NATURALLY OCCURRING DISACCHARIDES, OLIGOSACCHARIDES OR POLYSACCHARIDES
- C13K1/00—Glucose; Glucose-containing syrups
- C13K1/02—Glucose; Glucose-containing syrups obtained by saccharification of cellulosic materials
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- General Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Emergency Medicine (AREA)
- Biochemistry (AREA)
- Health & Medical Sciences (AREA)
- Polysaccharides And Polysaccharide Derivatives (AREA)
- Saccharide Compounds (AREA)
- Processing Of Solid Wastes (AREA)
- Preparation Of Compounds By Using Micro-Organisms (AREA)
- Jellies, Jams, And Syrups (AREA)
- Absorbent Articles And Supports Therefor (AREA)
- Medicines Containing Material From Animals Or Micro-Organisms (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
Water-soluble saccharides (mainly glucose and oligomeric glucose) are obtained by treating cellolignin with gaseous hydrogen fluoride - optionally diluted with an inert gas - at temperatures between about 20 and 120°C, preferably between about 40 and 80°C. The cellolignin used is a natural cellulose-containing material which has been pre-hydrolyzed with dilute mineral acids,or else waste paper or the like of low hemicellulose content. The water-soluble saccharides obtained by the process can be subjected to further pro-cessing in a known manner.
Water-soluble saccharides (mainly glucose and oligomeric glucose) are obtained by treating cellolignin with gaseous hydrogen fluoride - optionally diluted with an inert gas - at temperatures between about 20 and 120°C, preferably between about 40 and 80°C. The cellolignin used is a natural cellulose-containing material which has been pre-hydrolyzed with dilute mineral acids,or else waste paper or the like of low hemicellulose content. The water-soluble saccharides obtained by the process can be subjected to further pro-cessing in a known manner.
Description
- 2 -Cellulose-con-taining ma-terials occur in nature in large numbers and in great variety. Wood is an example of such a known natural cellulose-containing material. It consists essentially of cellulose (a material mainly built up from glucose units), hemi-cellulose (a substance mainly built up from pentoses and hexoses) and lignin (a polymeric substance havingaromatic ringswhich aresubstituted bymethoxy groups). ~ood is utilized in many di~-ferent ways~ for example for the pro-duction of heat (burning) and as a building material inthe furniture and building industry a~d the like; utiliz-ation o~ wood by purely chemical means is also possible.
Chemical disaggregation processes~ which effect not only the separation of wood into its constituents, hemi-cellulose, cellulose and lignin, but also the degradationand modification ofthe latter 7 have alreadybeen known for a longtime. As a rule, chemical processes yieldaqueous solutions o~ monomeric, dimeric and oligomeric saccharides, which may be subjected to subsequent hydrolysis to glucose or can be subjected direct to fermentation to give ethanol, or to concentrating or to evaporation to dryness.
E~amples of possible fields of use of the products thus obtained are in the sphere of cattle feed additives or, preferably1inthat o~ raw materials for fermentation.
II1 chemical processes for wood saccharification, two principles have been used on a large industrial scale in the past: the disaggregationof wood with concentrated aqueous hydrochloric acid (Bergius-Rheinau-Udic) anddis-a~Jsregation with dilute sul~uric acid (Scho~ler-Tornesch-Madison); in this con-text see, ~or example, Ullmanns Encyclop~die der ~echnischen Chemie ("Ullmann's Encyclopedia of Industrial Chemistry"), 3rd Edition, Volume 8 (1957) 9 pages 591 et seq.
The disag~regation ~cellulose-containing raw materials with anhydrous hydrofluoric acid has also already been investigated onseveral occasions. Here, however, none of the processes hitherto disclosed has yet led to a technically satisfactory solution o~ the problem.
German Patent Speci~ication 560,535 describes the disaggre-~ationof wood w;th pure HF,in the form of liquid or vapor, at low temperatures, the HF being recycled by being evaporated or blown off and subsequently condensed.
As a continuation o~ this work, German Patent Speci~ication 585,318 describes a process Ior the disaggregation o~ ~ood Wi~
gaseous hydrogen fluoride, which operates in three stages via absorption of HF on wood at 10-20C,~lisaggregation a.t 20 50C and desorption at 100-150C, it being possible to dilute the ~ with a stream of inert gas. The out-lay on cooling for condensing the HF has a disadvantageous effect here, as has also the fact that in the condensa-tion stage initially there is only a very non-uniform distribution of the hydrogen fluoride on the reaction material, a circumstance which can only be counteracted by very long residence times or by greatly increasing the amount o~ hydrogen fluoride used, otherwise the yields are greatly impaired German Patent Specification 606,009 describes an extraction process using liquid E~which, however, ~ 3~7 requires large quan-tities of HF and has the disadvantage that large quantities of heat have to be supplled in order to evapora~e the hydrogen fluoride fro~l the extract and extraction residue (lignin),and whichhavetobe removed again in the subsequent condensation process. More precise data concerning yields in processes of this ~ind are to be found in Angew. Chem. 46 (1933) 113/7, where by absorbing HF from the gas phase in an externally cooled vessel at 0C 32% of sugar is achieved, relative to car-bohydra-tes present, at a loading of 50% by weight of HF
relative to wood, and 86% of sugar, relative to ca~bo~
hydrates, is achieved at a loading of 100% by wei~h-t.
No further in~or~ation concerning the recycling of the HF is given in this reference~
All these processes suffer from the disadvantage that they consume large quantities of expensive hydro-fluoric acid, that the recovery of HF from the reaction products is very exponsive and that large losses of HF
take place in practice.
A more advanced process is described i~ Austrian Patent Specifioation 147,494, where the existing state of the art is described as follows: 'IIf the reaction is carried out using highly concentrated or anhydrous hydrofluoric acid in a liquid or gaseous state at low terQperatures, the ~egradation of the wood only proceeds in a very non-unifo~n manner and there~ore incompletely.
Fir~tly, at suoh low t~mperatures the distribu -tion of the hydrogen fluoride, wll:ich is pre~ent ~s a fine r~ist in the air , is ~rexy non-uniform ~
t3'J
. 5 ~
the more so as the air ~Jhich is presen-t makes i-t difficult -to achieve a unlforrn reaction. On the other ha~d,it is known that,in thesaccharjlication of ~oodwith conce~trated hydrogen fluoride,not onlyin aliquid but also ina gaseousstate, the particles of wood react rapidly at their surface with the concentrated hydrogen ~fluoride, form a hard, rather impenetrable skin and shrirLk whereby the further penetration of the gas into the interior is impeded. In addition, the penetration of the wood particles is already rendered difficu3t by the air present in the cells~ Thus an outer crust which encloses unsaccharified material and prevents further saccharifi-cation is formed very rapid]y. In order to remove these drawbacks, i-t has already also been proposed to carry out the disaggregation with conce~trated li~[u~d hydro- -fluGric acid using an extraction process or to pre~ent the formation of crusts by mixing ine~t gases into the hydro-fluoric acid, in order thereby to achieve a more uniform andmore complel;e disa~gregation. Ho~ver, the extraction pro-cess operates with a disproportionately large excess ofhydrofluoric acid and the reaction material retains large quantities of hydrofluoric acid without preventing the ~orrnation of cr~sts, with ali its disadvantages.
Although dilution with inert gases can somewhat reduce the formation of crusts, it can never elimina-te thls and lt also cannot result in the gas penetra-ting uniformly into the interior of the wood, since the wood is indeed filled with air. This is because, as is known, wood is only composed to a very small ex-ten-t o~ ligneous matter and its :L I ~ ;3~'ît largest component by far is air, which is presen-t between and within -the wood cells. A virtually anhydrous wood is composed, for example, OL approx. 15% of ligneous matter and approx. 85% of air. Since the wood cells are extremely small in relatlon to -the size of a piece of wood, however thoroughly it may have been comminuted, the airconten-t plays a predominant part, even in ~he case of sawdust."
Hardening of the surface of wood particles also appears to have been observed in saccharifying wood with aqueous mineral acids, such as aqueous hydrochloric or sulfuric acid, since9 for example, in Z. Angew. Chem. ~7 (1924) 221 the substances present in wood, such as lignin~
mannan, galactan and the like, are described as "incrus-tants" ~hich should be removed,if possible, prior tothe actual wood saccharification process, additionally because of interfering degradation products (furfural, acetic acid, formic acid and -the like) For -their remo~al itwouldhave beenpossible -since thesel'incrus~ants"
wereknown tobe hydrolyzable -toconsidertheuse ofa kind of ~'pre hydrolysis" with dilu-te mineral acid at eleva-ted temperature and, if appropriate, eleva-ted pressure, also in the case of wood saccharification by means of hydrogen fluoride. However, considera-tion had not been given to a pre-hydrolysis of this type; instead, i-t was suggested by Hoch and Bohune~c that in order to avoid the disadvantages described above a vacuum of approx. 30mm Hg be employed for ~rood saccharification with hydrogen ~luoride [Austrian Patent Specification 147,494 and J~ 3i7 Patent or ~ddition 151,2~ the Hoch and Bohunek wood saccharification process using hydrogen fluoride is also described in the journal "Holz Roh~ und ~Jerkstoff" 1, pages 342~344 (19~8)].
Disadvantages of these process~ are the difficulties of industrial implementation which necessarily occur when operating in vacuGI and also the dif~iculties caused by the relatively complicated manner in which the reactions are carried out. A drawback from which all the processes suffer is the formation of mixtures of pentoses and hexoses as a result of simultaneous hydrolysis of the hemicelluloses and o~ the cellu]ose of the wood.
A further problem is the removal of the acetic acid formed in the hydrolysis of hemicellulose, which renders difficult the circulation o~ the ~F as loss-fr~e as possible, and also the fact tha~ the pentoses are easily decomposed to give ~urfural.
It has now been found, surprisingly, that the above-described disadvantages of the stat~ of the art Ean be avoided and that it is possible to ~accharify cellulose readily , if the v~getable materials are disaygregated with anhydrous, gaseous ~F, not in their natural form, but in the form of 'tcelloli~nin" which is obtained a~ter a pre-treatment.
"Cello'ignln" is to be lmders-tood here as meaning vegetable materials, such as wood, straw, bagasse and similar raw materials having been subjected to a pre~
hydrolysis -~hich is-in itsel~ known.
This pre-hydrolysis, which is in itsel~ know~, of L~ 3'~
Chemical disaggregation processes~ which effect not only the separation of wood into its constituents, hemi-cellulose, cellulose and lignin, but also the degradationand modification ofthe latter 7 have alreadybeen known for a longtime. As a rule, chemical processes yieldaqueous solutions o~ monomeric, dimeric and oligomeric saccharides, which may be subjected to subsequent hydrolysis to glucose or can be subjected direct to fermentation to give ethanol, or to concentrating or to evaporation to dryness.
E~amples of possible fields of use of the products thus obtained are in the sphere of cattle feed additives or, preferably1inthat o~ raw materials for fermentation.
II1 chemical processes for wood saccharification, two principles have been used on a large industrial scale in the past: the disaggregationof wood with concentrated aqueous hydrochloric acid (Bergius-Rheinau-Udic) anddis-a~Jsregation with dilute sul~uric acid (Scho~ler-Tornesch-Madison); in this con-text see, ~or example, Ullmanns Encyclop~die der ~echnischen Chemie ("Ullmann's Encyclopedia of Industrial Chemistry"), 3rd Edition, Volume 8 (1957) 9 pages 591 et seq.
The disag~regation ~cellulose-containing raw materials with anhydrous hydrofluoric acid has also already been investigated onseveral occasions. Here, however, none of the processes hitherto disclosed has yet led to a technically satisfactory solution o~ the problem.
German Patent Speci~ication 560,535 describes the disaggre-~ationof wood w;th pure HF,in the form of liquid or vapor, at low temperatures, the HF being recycled by being evaporated or blown off and subsequently condensed.
As a continuation o~ this work, German Patent Speci~ication 585,318 describes a process Ior the disaggregation o~ ~ood Wi~
gaseous hydrogen fluoride, which operates in three stages via absorption of HF on wood at 10-20C,~lisaggregation a.t 20 50C and desorption at 100-150C, it being possible to dilute the ~ with a stream of inert gas. The out-lay on cooling for condensing the HF has a disadvantageous effect here, as has also the fact that in the condensa-tion stage initially there is only a very non-uniform distribution of the hydrogen fluoride on the reaction material, a circumstance which can only be counteracted by very long residence times or by greatly increasing the amount o~ hydrogen fluoride used, otherwise the yields are greatly impaired German Patent Specification 606,009 describes an extraction process using liquid E~which, however, ~ 3~7 requires large quan-tities of HF and has the disadvantage that large quantities of heat have to be supplled in order to evapora~e the hydrogen fluoride fro~l the extract and extraction residue (lignin),and whichhavetobe removed again in the subsequent condensation process. More precise data concerning yields in processes of this ~ind are to be found in Angew. Chem. 46 (1933) 113/7, where by absorbing HF from the gas phase in an externally cooled vessel at 0C 32% of sugar is achieved, relative to car-bohydra-tes present, at a loading of 50% by weight of HF
relative to wood, and 86% of sugar, relative to ca~bo~
hydrates, is achieved at a loading of 100% by wei~h-t.
No further in~or~ation concerning the recycling of the HF is given in this reference~
All these processes suffer from the disadvantage that they consume large quantities of expensive hydro-fluoric acid, that the recovery of HF from the reaction products is very exponsive and that large losses of HF
take place in practice.
A more advanced process is described i~ Austrian Patent Specifioation 147,494, where the existing state of the art is described as follows: 'IIf the reaction is carried out using highly concentrated or anhydrous hydrofluoric acid in a liquid or gaseous state at low terQperatures, the ~egradation of the wood only proceeds in a very non-unifo~n manner and there~ore incompletely.
Fir~tly, at suoh low t~mperatures the distribu -tion of the hydrogen fluoride, wll:ich is pre~ent ~s a fine r~ist in the air , is ~rexy non-uniform ~
t3'J
. 5 ~
the more so as the air ~Jhich is presen-t makes i-t difficult -to achieve a unlforrn reaction. On the other ha~d,it is known that,in thesaccharjlication of ~oodwith conce~trated hydrogen fluoride,not onlyin aliquid but also ina gaseousstate, the particles of wood react rapidly at their surface with the concentrated hydrogen ~fluoride, form a hard, rather impenetrable skin and shrirLk whereby the further penetration of the gas into the interior is impeded. In addition, the penetration of the wood particles is already rendered difficu3t by the air present in the cells~ Thus an outer crust which encloses unsaccharified material and prevents further saccharifi-cation is formed very rapid]y. In order to remove these drawbacks, i-t has already also been proposed to carry out the disaggregation with conce~trated li~[u~d hydro- -fluGric acid using an extraction process or to pre~ent the formation of crusts by mixing ine~t gases into the hydro-fluoric acid, in order thereby to achieve a more uniform andmore complel;e disa~gregation. Ho~ver, the extraction pro-cess operates with a disproportionately large excess ofhydrofluoric acid and the reaction material retains large quantities of hydrofluoric acid without preventing the ~orrnation of cr~sts, with ali its disadvantages.
Although dilution with inert gases can somewhat reduce the formation of crusts, it can never elimina-te thls and lt also cannot result in the gas penetra-ting uniformly into the interior of the wood, since the wood is indeed filled with air. This is because, as is known, wood is only composed to a very small ex-ten-t o~ ligneous matter and its :L I ~ ;3~'ît largest component by far is air, which is presen-t between and within -the wood cells. A virtually anhydrous wood is composed, for example, OL approx. 15% of ligneous matter and approx. 85% of air. Since the wood cells are extremely small in relatlon to -the size of a piece of wood, however thoroughly it may have been comminuted, the airconten-t plays a predominant part, even in ~he case of sawdust."
Hardening of the surface of wood particles also appears to have been observed in saccharifying wood with aqueous mineral acids, such as aqueous hydrochloric or sulfuric acid, since9 for example, in Z. Angew. Chem. ~7 (1924) 221 the substances present in wood, such as lignin~
mannan, galactan and the like, are described as "incrus-tants" ~hich should be removed,if possible, prior tothe actual wood saccharification process, additionally because of interfering degradation products (furfural, acetic acid, formic acid and -the like) For -their remo~al itwouldhave beenpossible -since thesel'incrus~ants"
wereknown tobe hydrolyzable -toconsidertheuse ofa kind of ~'pre hydrolysis" with dilu-te mineral acid at eleva-ted temperature and, if appropriate, eleva-ted pressure, also in the case of wood saccharification by means of hydrogen fluoride. However, considera-tion had not been given to a pre-hydrolysis of this type; instead, i-t was suggested by Hoch and Bohune~c that in order to avoid the disadvantages described above a vacuum of approx. 30mm Hg be employed for ~rood saccharification with hydrogen ~luoride [Austrian Patent Specification 147,494 and J~ 3i7 Patent or ~ddition 151,2~ the Hoch and Bohunek wood saccharification process using hydrogen fluoride is also described in the journal "Holz Roh~ und ~Jerkstoff" 1, pages 342~344 (19~8)].
Disadvantages of these process~ are the difficulties of industrial implementation which necessarily occur when operating in vacuGI and also the dif~iculties caused by the relatively complicated manner in which the reactions are carried out. A drawback from which all the processes suffer is the formation of mixtures of pentoses and hexoses as a result of simultaneous hydrolysis of the hemicelluloses and o~ the cellu]ose of the wood.
A further problem is the removal of the acetic acid formed in the hydrolysis of hemicellulose, which renders difficult the circulation o~ the ~F as loss-fr~e as possible, and also the fact tha~ the pentoses are easily decomposed to give ~urfural.
It has now been found, surprisingly, that the above-described disadvantages of the stat~ of the art Ean be avoided and that it is possible to ~accharify cellulose readily , if the v~getable materials are disaygregated with anhydrous, gaseous ~F, not in their natural form, but in the form of 'tcelloli~nin" which is obtained a~ter a pre-treatment.
"Cello'ignln" is to be lmders-tood here as meaning vegetable materials, such as wood, straw, bagasse and similar raw materials having been subjected to a pre~
hydrolysis -~hich is-in itsel~ known.
This pre-hydrolysis, which is in itsel~ know~, of L~ 3'~
3 --wood comprises a relatively short treatment, with very - dilute mineral acid,at elevated temperatures and pressures, in which essentially the pentosans and hexosans present in the hemicelluloses are split as far as the monomer units, such as, for example, xylo~e or mannose Depending on the reaction condi-tions, the latter can subsequently be isolated as such or undergo further changes, for example dehydration to give furfural or hydroxymethylfurfural (compare IJllmann, loc. cit., Volume 7 (1957), page 711)~ In addition to fermentation, the reduction of xylose to xylltol may be mentioned as a further example of the industrial utilization of hemi-cellulose degradation products It is thus possible to obtain valuable products ~rom wood by pre-hydrolysis ~rior to using the disaggregation process according to the invention.
Cellolignin is also to be understood ~ere as meaning paper material (for example was-te paper) which has a low content of hemicelluloses. In the pre-hydrolysis of wood,its structure is la~gely retainedbut the cellolignin which can thus be obtained has a much more crumbly and porous nature compared wi-th the natural state~ so -that HF, including mixtures with air or ano-ther inert carrier gas, can penetrate readily without encrus-tation o~ the sur~ace taking place, It is not necessaryto operate in vacuo.
A further important advantage of the use cf cello-lignin instead of nati~e wood is that the reaction material is then appreciably simpler to handle from the '7 _ 9 point of view of process technology This is due, on the one hand, to the fact that, compared with wood o~
the same particle size, cellolignin has an apparent volume which is only approx. half as large and i~ thus exhibits an appreciably smaller degree of shrinking when disaggregated with hydrogen fluoride gas, which makes matters considerably easier, for example in dimensioning reactors.
Secondly, reaction material composed of cellolignin remains pourable and free-~lowing, even when charged with hydrogen fluoride, whilst re~ction material composed of native wood has a strong tend~ncy to gum up due to r~si~ous constituent~, and al~o because of cleavage products of the hemicellu-loses, a~d is difficult to con~ey.
Naturall~, such a tendency to gum up also impedes the desorption of hydrogen fluoride, particularly if the latter process step is intendedto takeplace rapidlyand as quantitativelyas possible. When celloli~nin is used as the substrate, however, this is possible withou-t difficulties.
Furthermore, in this process it is no longer nec~ssary to separa-te the mixtures of sugars ~ormed in the hydrolysis of hemicellulose from -the oligomeric glucose structural units ~ormed in -the hydrolysis of celluloseg or from glucose, which makes it possible to utilize these various sugars more easily in ~ermentation~
It is also an advantage that no acetic ac,d and furfural are fornrd Ln the disaggregation of cello-lignin, so that the ~i can be circulated without having to condense these components. Difficulty in .~.. .q ~ 4 separa-tion and losses of ~ are thus avoided.
A further advantage is -tha-t it ls possible to absorb ~ onto cellolignin above the boiling point of HF, so that external cooling is no longer necessary. It 5 was also surprising~ tha~ yields of ,gO% o-f glucose or oligomeric glucoseg relative to the cellulose employed in the cellolignin, are achieved in a simple mar~er in the process according to the invention, -the sugars produced being high-grade in quality, that is to say almost colorless.
The invention therefore relates to a process for obtaining water-soluble saccharides (glucose or oligomeric glucose) from cellulose-containing material by treating the latter with gaseous hydrogen fluoride -Optiona11y - diluted with an inert gas - at temperatures between about 20 and 120C 7 preferably between about 40 and 80C; the process comprises subjecting cellolignin - to a treatment with hydrogen fluoride.
Cellolignin is to be understood here, as defined above, as a ma-terial composed largely of cellulose and lignin.
In view of the state of the art, in which the most recent process to be developed toa majorextent ~Hoch and Bohunek, loc. cit.) attempts -to remove -the dis-advantages associated with the non-uniformdisaggregation and with the formation ofencrustations,by usingthe expensive vacu~nmethod- although thefact that hemicelluloses canbe hydrolyze~ readilywas knoYm (Oesterr. Chem.-Zeitg 40, 5 et seq. ~1937)) the use of pre hydrolyzed material was in no way obvious. .It was, therefore, rath~r surprising that this measure, which lies inthe opposite directiontothatsuggested bythe state of the art, permits uniform and problem-free saccharification of wood and materials similar -to wood.
The cellolignin which, in accordance with the in~ention, is particularly suitable for degradation to give water-soluble sugars is ob-tained by pre-hydrolysis of natur~ cellulose-containing material (wood, straw, bagasse and the like) with dilute a~ueous mineral acid, preferably dilute hydrochloric or sulfuric acid. As already pointed out in describing the state of the art, the process of pre-hydrolysis is known in wood saccharifi-cation and is also to be found in fairly recent literature, such as Ullmanns Encyclop~die der technischen Chemie ("Ullmann's Encyclopedia of Industrial Chemistry")~ 3rd . Edition, Volume 8 (1957), pages 591-595,and also in the book by W. Sandermann, t'Chemische Holzverwertung"
e Chemical Utilization of Wood"), Bayrischer Landwirtschaftverlag, Munich 1963, page 253.
It comprises a relatively brief treatment of -the natural starting material with a ve~ dilutemineral acid at an elevated temperature (preferably bet~een about 100 and 160C)andunder aneleva-ted pressure (prefe~ably up to about 1~ atmospheres) 3 in the course of which essen tially the pentosans and hexosans present in the hemi-celluloses are split as far as the monomeric units (x~ylose, arabinose, mannose and the like~. Depending on the reaction condi-tions, the latter can then be isolated.
- 12 _ as such or undergo further changec, for example to give furfural and the like by dehydration.
They are preferably ernployed as raw materials for fermentation or for the production o~ xylitol waste pa~er of lcw hemicellulose content is also very suitable for use as the s~ting material in the process of the invention.
The disa~greaation process accordmg to the inve~tion can, for example, be effected either by bringing -the pre-treated material (cellolignin or, for example, paper 1~ shredder material) which has been dried to a moisture content of 0 to about 20%, preferably about 2~5%, and has been comminuted if required, into contact with HF gas, optionally mixed with air or another inert carrier gas discontinuously in a suitable stirred vessel made of a material resistant to hydrogen fluoride, or by passing a gas mixture con-taining HF, advantageously in a conveying equipment, in countercurrent toa con-tinuous stream of the substrate to be disagqreyated.
As a result Q~ the heat of reaction, whichisliber-Z0 ated spontaneously, the temperature rises and can be keptwithin the desired rangebetween about 20 and 120C, pre-ferably be-tween 40 and 80C, by carrying out the reaction in a suitable manner, such as, for example,bydilutingwi-th inert gases ~5 The contac-t of the substrate wi-th hydrogen fluoride gas is maintained until one part by weight o~ the material has taken up about 0.2 to 3.0, preferably about 0.4 to 0.8, parts by ~eight of hydrogen fluoride.
It is then advantageous to continue the reaction .~ '7 by choosing, depending on the nature of the substrate and on the condi-tions of HF absorption, a residence time which is adequate to achieve a high yield. Longer resi-dence times are not disadvantageous, bu-t have no advan-tage either. The reaction times can be between 15minutes and several hours. Preferred reaction con-ditions are those in which a residence time of about 1 hour is not e~ceeded.
The subsequent HF desorption can be carried out in accordance with the state of the art by warming the re-action material andlor by evacuation or by treatment with a stream ofan inertgas ~for example nitrogen, air9 C02 or a rare gas) of suitable strengthg again with or without simultaneous warming ând/or evacuatingO ~he hydro-gen fluoride ~hus recovered can be isolated by condensa-tion or can be reacted directly with fresh substrate so as to produce a circulation of gaseous hydrogen ~luoride.
The further processing of the material which has now been disaggregated ("saccharified~) can also be carried out in a manner which is in itsel~ known, as described, for example, by K Fredel~agen and G. Cadenbach, Angewandte Chemie 46 (1933), pages 113 to 117. That is to say, for example, the material is extracted with hot water, insoluble lignin is fil-tered off, the small quanti-ty of hydrogen fluoride ~dhering is neutralized in the filtrate wi-th oalcium carbonate or calcium hydroxide and the mixture is concen-tra~ed.
In the procedureaccor~ing tothe invention, the quantity o~ "~,rood sugar" (or"straw sugar"and thelike) obtainedafterdryingthe residuefrom evaporation is inall casesmore tha~about 90~Oof the cellulos~present in thesub-strate (calculated on dry substance).
Because OI the high ~'sugar" yield,the exceptivnally simple and smooth performance of the process ~increased porosity of the substrate and thus easier penetration of HF) and also the energy-saving absorption of hydrogen fluoride (no cooling or vacuum required), the invention constitu-tes a not inconsiderable advance in this field.
The oligomeric glucose structural units can be employed for further utilization (fermentation to give ethanol, concentrating or evaporation and use as cattle feed additives or as raw materials ~or ~ermentation and the like) in the fcrm in which they are pro~uced or they can also be subjected in a manner which is in itself kno1~n to further hydrolysis to give monomeric glucose.
The invention will now be illustrated in greater detail by means of the following examples:
500 g of spruce cellolignin (59% of cellulose +
~l~ of lignin) of particle size approx. 2 mm were placed ina cylindrical 2 l vessel made o~ transparent polyethylene, fitted with a stirrer, a thermometer and a gas inlet, andweretreated with a mixture of air and hydrogen ~luoride gas,which is prepared by passingair overliquid hydro~
gen fluoride at 20C (waterbath)~ In the course o~
this treatment, the material ~Jas s-tirred slowlyand it turned dark brown. The air stream and the vapori~ation o~ ~
were regulated in such a way that the internal temperature did not exceed 70C.
After 300 g of hydrogen fluoride had been absorbed, care was taken to maintain an internal tempera-ture of 50°C for 30 minutes. The hydrogen fluoride was then expelled by passing in warm air, with continued stirring. In so doing, part of the heat of desorption required was also supplied by external heating. The desorption was continued with a continually increasing temperature until a hydrogen fluoride content of about 5%
in the substrate had been reached. The material was then transferred to a fluid bed dryer and hydrogen fluoride was blown off until a residual quantity of approx. 0.5%
had been reached. The HF/air mixture thus produced could be used directly for further batches.
The contents of the reactor were then digested for 15 minutes with approx. 2 1 of hot water, were suction-strained and rinsed with a little water. The dark brown filter residue weighed about 250 g after drying and was thus composed of 82% of lignin and 18% of still not disaggregated cellulose. The filtrate was rendered alkaline, while still hot, with technical calcium hydroxide, the excess of hydroxyl ions was neutralized with carbon dioxide, and calcium fluoride and calcium carbonate were filtered off, if necessary by means of a filtration aid. The clear, slightly yellow, neutral solution was evaporated to dry-ness in vacuo. This gave approx. 250 g of slightly yellowish wood sugar, corresponding to 85% of the theore-ical yield. The product gave a clear solution in water and contained between 2 and 10% of monomeric glucose, the remainder being composed of oligomeric glucose.
Examples 2-13 A jacketed -tube, resistant to hydrogen fluoride, of length 30 cm and internal width 4 cm in a horizontal position was filled about half full with 30 g of cello-lignin of particle size 1-2 mm, and was closed at both ends with bored rubber stoppersO Cne of tw~-~n steel tube, perforated overthe~ entire length, was placed in the layer of cellolignin and the other in the free ~ce above the latter These tubes led to the exterior on both sides through holes in the sealing stoppers and were used for the introduction or r~al of~/air mixture, respectively.
This made it possible to treat the cellolignin wi-th gas at right angles to the surface of the bed. The material was allowed to absorb hydrogen fluoride and appropriate heating was used to ensure an internal temperature of 50C
during the subse~uent residence time. Hot air, instead of the HF/air mix-ture, was then blown through the bed for 15 minutes~and the reaction material thus obtained9 which had been freed from the bulk of the hydrogen fluoride, was worked up as described in Example 1.
The yields corresponding to differen-t quantities of HF absorbed and residence time are sho~rn in -the following table.
EYampleH~ absorbed Residence time Yield of wood No. ~g] [minutes] ~ugar ~f theor. Yalue ~t 15 120 ~9'5 56 7 19 120 15 ~8 10 8 20 120 ]6 94 12 19 30 15 ~8 Example 14 In a long, horizontal tube made of material resis-tant to hydrogen fluoride in which a free-flowing soli.d can be propelled continuously by means of a screw conveyor, 20 a hydrogen fluoridelcarrier gas mixture was passed in counter-~ent to a contm~ous charge of.celloli~nLn at such a rate that the material at the E~ inlet end of the -tube had a content of approx. 600/o o~ HF, relative to cellolignin,whilst only pure carrier gas flowed out at the cellolignin inlet end.
25 The material was continuously discharged at the HF inlet end, while fresh cellolignin was recharged at the opposi-te end. After having pas~ed a re~idence tisne section for half an hour , the ma$erial discharged ~a freed from hydrogen fluoride by blowing the latter off~
30 and the IIF rich gas mixture thus obtained was fed bac~
!
3t7 into the reaction tube. The disaggregated cellolignin was worked up in the manner described in Example 1. The yield of wood sugar amounted to approx.85% of the theoretical value.
Example 15 150 g of shredded newspaper material were treated with a hydrogen fluoride/air mixture in the manner des-cribed in greater detail in Example 1. After a resi-dence time of one hour at 50C the reaction mixture was freed from the hydragen fluoride, down to a residual content of 2%, by passing in a stream of warm air, and ~e dark-colored residue was digested with hot water.
After filtering and drying, this gave 50 g of insoluble material, mainly composed of lignin. The filtrate was neutralized with calcium hydroxide and the calcium fluori~ was filtered off with suction. The residue from the evaporation of the filtrate weighed 80 g and con-tained approx. 10% of monomeric glucose (remainder:
oligomeric glucose).
Cellolignin is also to be understood ~ere as meaning paper material (for example was-te paper) which has a low content of hemicelluloses. In the pre-hydrolysis of wood,its structure is la~gely retainedbut the cellolignin which can thus be obtained has a much more crumbly and porous nature compared wi-th the natural state~ so -that HF, including mixtures with air or ano-ther inert carrier gas, can penetrate readily without encrus-tation o~ the sur~ace taking place, It is not necessaryto operate in vacuo.
A further important advantage of the use cf cello-lignin instead of nati~e wood is that the reaction material is then appreciably simpler to handle from the '7 _ 9 point of view of process technology This is due, on the one hand, to the fact that, compared with wood o~
the same particle size, cellolignin has an apparent volume which is only approx. half as large and i~ thus exhibits an appreciably smaller degree of shrinking when disaggregated with hydrogen fluoride gas, which makes matters considerably easier, for example in dimensioning reactors.
Secondly, reaction material composed of cellolignin remains pourable and free-~lowing, even when charged with hydrogen fluoride, whilst re~ction material composed of native wood has a strong tend~ncy to gum up due to r~si~ous constituent~, and al~o because of cleavage products of the hemicellu-loses, a~d is difficult to con~ey.
Naturall~, such a tendency to gum up also impedes the desorption of hydrogen fluoride, particularly if the latter process step is intendedto takeplace rapidlyand as quantitativelyas possible. When celloli~nin is used as the substrate, however, this is possible withou-t difficulties.
Furthermore, in this process it is no longer nec~ssary to separa-te the mixtures of sugars ~ormed in the hydrolysis of hemicellulose from -the oligomeric glucose structural units ~ormed in -the hydrolysis of celluloseg or from glucose, which makes it possible to utilize these various sugars more easily in ~ermentation~
It is also an advantage that no acetic ac,d and furfural are fornrd Ln the disaggregation of cello-lignin, so that the ~i can be circulated without having to condense these components. Difficulty in .~.. .q ~ 4 separa-tion and losses of ~ are thus avoided.
A further advantage is -tha-t it ls possible to absorb ~ onto cellolignin above the boiling point of HF, so that external cooling is no longer necessary. It 5 was also surprising~ tha~ yields of ,gO% o-f glucose or oligomeric glucoseg relative to the cellulose employed in the cellolignin, are achieved in a simple mar~er in the process according to the invention, -the sugars produced being high-grade in quality, that is to say almost colorless.
The invention therefore relates to a process for obtaining water-soluble saccharides (glucose or oligomeric glucose) from cellulose-containing material by treating the latter with gaseous hydrogen fluoride -Optiona11y - diluted with an inert gas - at temperatures between about 20 and 120C 7 preferably between about 40 and 80C; the process comprises subjecting cellolignin - to a treatment with hydrogen fluoride.
Cellolignin is to be understood here, as defined above, as a ma-terial composed largely of cellulose and lignin.
In view of the state of the art, in which the most recent process to be developed toa majorextent ~Hoch and Bohunek, loc. cit.) attempts -to remove -the dis-advantages associated with the non-uniformdisaggregation and with the formation ofencrustations,by usingthe expensive vacu~nmethod- although thefact that hemicelluloses canbe hydrolyze~ readilywas knoYm (Oesterr. Chem.-Zeitg 40, 5 et seq. ~1937)) the use of pre hydrolyzed material was in no way obvious. .It was, therefore, rath~r surprising that this measure, which lies inthe opposite directiontothatsuggested bythe state of the art, permits uniform and problem-free saccharification of wood and materials similar -to wood.
The cellolignin which, in accordance with the in~ention, is particularly suitable for degradation to give water-soluble sugars is ob-tained by pre-hydrolysis of natur~ cellulose-containing material (wood, straw, bagasse and the like) with dilute a~ueous mineral acid, preferably dilute hydrochloric or sulfuric acid. As already pointed out in describing the state of the art, the process of pre-hydrolysis is known in wood saccharifi-cation and is also to be found in fairly recent literature, such as Ullmanns Encyclop~die der technischen Chemie ("Ullmann's Encyclopedia of Industrial Chemistry")~ 3rd . Edition, Volume 8 (1957), pages 591-595,and also in the book by W. Sandermann, t'Chemische Holzverwertung"
e Chemical Utilization of Wood"), Bayrischer Landwirtschaftverlag, Munich 1963, page 253.
It comprises a relatively brief treatment of -the natural starting material with a ve~ dilutemineral acid at an elevated temperature (preferably bet~een about 100 and 160C)andunder aneleva-ted pressure (prefe~ably up to about 1~ atmospheres) 3 in the course of which essen tially the pentosans and hexosans present in the hemi-celluloses are split as far as the monomeric units (x~ylose, arabinose, mannose and the like~. Depending on the reaction condi-tions, the latter can then be isolated.
- 12 _ as such or undergo further changec, for example to give furfural and the like by dehydration.
They are preferably ernployed as raw materials for fermentation or for the production o~ xylitol waste pa~er of lcw hemicellulose content is also very suitable for use as the s~ting material in the process of the invention.
The disa~greaation process accordmg to the inve~tion can, for example, be effected either by bringing -the pre-treated material (cellolignin or, for example, paper 1~ shredder material) which has been dried to a moisture content of 0 to about 20%, preferably about 2~5%, and has been comminuted if required, into contact with HF gas, optionally mixed with air or another inert carrier gas discontinuously in a suitable stirred vessel made of a material resistant to hydrogen fluoride, or by passing a gas mixture con-taining HF, advantageously in a conveying equipment, in countercurrent toa con-tinuous stream of the substrate to be disagqreyated.
As a result Q~ the heat of reaction, whichisliber-Z0 ated spontaneously, the temperature rises and can be keptwithin the desired rangebetween about 20 and 120C, pre-ferably be-tween 40 and 80C, by carrying out the reaction in a suitable manner, such as, for example,bydilutingwi-th inert gases ~5 The contac-t of the substrate wi-th hydrogen fluoride gas is maintained until one part by weight o~ the material has taken up about 0.2 to 3.0, preferably about 0.4 to 0.8, parts by ~eight of hydrogen fluoride.
It is then advantageous to continue the reaction .~ '7 by choosing, depending on the nature of the substrate and on the condi-tions of HF absorption, a residence time which is adequate to achieve a high yield. Longer resi-dence times are not disadvantageous, bu-t have no advan-tage either. The reaction times can be between 15minutes and several hours. Preferred reaction con-ditions are those in which a residence time of about 1 hour is not e~ceeded.
The subsequent HF desorption can be carried out in accordance with the state of the art by warming the re-action material andlor by evacuation or by treatment with a stream ofan inertgas ~for example nitrogen, air9 C02 or a rare gas) of suitable strengthg again with or without simultaneous warming ând/or evacuatingO ~he hydro-gen fluoride ~hus recovered can be isolated by condensa-tion or can be reacted directly with fresh substrate so as to produce a circulation of gaseous hydrogen ~luoride.
The further processing of the material which has now been disaggregated ("saccharified~) can also be carried out in a manner which is in itsel~ known, as described, for example, by K Fredel~agen and G. Cadenbach, Angewandte Chemie 46 (1933), pages 113 to 117. That is to say, for example, the material is extracted with hot water, insoluble lignin is fil-tered off, the small quanti-ty of hydrogen fluoride ~dhering is neutralized in the filtrate wi-th oalcium carbonate or calcium hydroxide and the mixture is concen-tra~ed.
In the procedureaccor~ing tothe invention, the quantity o~ "~,rood sugar" (or"straw sugar"and thelike) obtainedafterdryingthe residuefrom evaporation is inall casesmore tha~about 90~Oof the cellulos~present in thesub-strate (calculated on dry substance).
Because OI the high ~'sugar" yield,the exceptivnally simple and smooth performance of the process ~increased porosity of the substrate and thus easier penetration of HF) and also the energy-saving absorption of hydrogen fluoride (no cooling or vacuum required), the invention constitu-tes a not inconsiderable advance in this field.
The oligomeric glucose structural units can be employed for further utilization (fermentation to give ethanol, concentrating or evaporation and use as cattle feed additives or as raw materials ~or ~ermentation and the like) in the fcrm in which they are pro~uced or they can also be subjected in a manner which is in itself kno1~n to further hydrolysis to give monomeric glucose.
The invention will now be illustrated in greater detail by means of the following examples:
500 g of spruce cellolignin (59% of cellulose +
~l~ of lignin) of particle size approx. 2 mm were placed ina cylindrical 2 l vessel made o~ transparent polyethylene, fitted with a stirrer, a thermometer and a gas inlet, andweretreated with a mixture of air and hydrogen ~luoride gas,which is prepared by passingair overliquid hydro~
gen fluoride at 20C (waterbath)~ In the course o~
this treatment, the material ~Jas s-tirred slowlyand it turned dark brown. The air stream and the vapori~ation o~ ~
were regulated in such a way that the internal temperature did not exceed 70C.
After 300 g of hydrogen fluoride had been absorbed, care was taken to maintain an internal tempera-ture of 50°C for 30 minutes. The hydrogen fluoride was then expelled by passing in warm air, with continued stirring. In so doing, part of the heat of desorption required was also supplied by external heating. The desorption was continued with a continually increasing temperature until a hydrogen fluoride content of about 5%
in the substrate had been reached. The material was then transferred to a fluid bed dryer and hydrogen fluoride was blown off until a residual quantity of approx. 0.5%
had been reached. The HF/air mixture thus produced could be used directly for further batches.
The contents of the reactor were then digested for 15 minutes with approx. 2 1 of hot water, were suction-strained and rinsed with a little water. The dark brown filter residue weighed about 250 g after drying and was thus composed of 82% of lignin and 18% of still not disaggregated cellulose. The filtrate was rendered alkaline, while still hot, with technical calcium hydroxide, the excess of hydroxyl ions was neutralized with carbon dioxide, and calcium fluoride and calcium carbonate were filtered off, if necessary by means of a filtration aid. The clear, slightly yellow, neutral solution was evaporated to dry-ness in vacuo. This gave approx. 250 g of slightly yellowish wood sugar, corresponding to 85% of the theore-ical yield. The product gave a clear solution in water and contained between 2 and 10% of monomeric glucose, the remainder being composed of oligomeric glucose.
Examples 2-13 A jacketed -tube, resistant to hydrogen fluoride, of length 30 cm and internal width 4 cm in a horizontal position was filled about half full with 30 g of cello-lignin of particle size 1-2 mm, and was closed at both ends with bored rubber stoppersO Cne of tw~-~n steel tube, perforated overthe~ entire length, was placed in the layer of cellolignin and the other in the free ~ce above the latter These tubes led to the exterior on both sides through holes in the sealing stoppers and were used for the introduction or r~al of~/air mixture, respectively.
This made it possible to treat the cellolignin wi-th gas at right angles to the surface of the bed. The material was allowed to absorb hydrogen fluoride and appropriate heating was used to ensure an internal temperature of 50C
during the subse~uent residence time. Hot air, instead of the HF/air mix-ture, was then blown through the bed for 15 minutes~and the reaction material thus obtained9 which had been freed from the bulk of the hydrogen fluoride, was worked up as described in Example 1.
The yields corresponding to differen-t quantities of HF absorbed and residence time are sho~rn in -the following table.
EYampleH~ absorbed Residence time Yield of wood No. ~g] [minutes] ~ugar ~f theor. Yalue ~t 15 120 ~9'5 56 7 19 120 15 ~8 10 8 20 120 ]6 94 12 19 30 15 ~8 Example 14 In a long, horizontal tube made of material resis-tant to hydrogen fluoride in which a free-flowing soli.d can be propelled continuously by means of a screw conveyor, 20 a hydrogen fluoridelcarrier gas mixture was passed in counter-~ent to a contm~ous charge of.celloli~nLn at such a rate that the material at the E~ inlet end of the -tube had a content of approx. 600/o o~ HF, relative to cellolignin,whilst only pure carrier gas flowed out at the cellolignin inlet end.
25 The material was continuously discharged at the HF inlet end, while fresh cellolignin was recharged at the opposi-te end. After having pas~ed a re~idence tisne section for half an hour , the ma$erial discharged ~a freed from hydrogen fluoride by blowing the latter off~
30 and the IIF rich gas mixture thus obtained was fed bac~
!
3t7 into the reaction tube. The disaggregated cellolignin was worked up in the manner described in Example 1. The yield of wood sugar amounted to approx.85% of the theoretical value.
Example 15 150 g of shredded newspaper material were treated with a hydrogen fluoride/air mixture in the manner des-cribed in greater detail in Example 1. After a resi-dence time of one hour at 50C the reaction mixture was freed from the hydragen fluoride, down to a residual content of 2%, by passing in a stream of warm air, and ~e dark-colored residue was digested with hot water.
After filtering and drying, this gave 50 g of insoluble material, mainly composed of lignin. The filtrate was neutralized with calcium hydroxide and the calcium fluori~ was filtered off with suction. The residue from the evaporation of the filtrate weighed 80 g and con-tained approx. 10% of monomeric glucose (remainder:
oligomeric glucose).
Claims (5)
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A process for the preparation of water-soluble saccharides in which cellolignin is subjected to treatment with gaseous hydrogen fluoride at a temperature of from about 20 to 120°C.
2. A process as claimed in claim 1 in which the gaseous hydrogen fluoride is diluted with an inert gas.
3. A process as claimed in claim 2 in which the process is carried out at a temperature of from about 40 to 80°C.
4. A process as claimed in claim 1, claim 2 or claim 3 in which the cellolignin is obtained by pre-hydrolysis of natural cellulose-containing material with dilute mineral acid at an elevated temperature and under an elevated pressure.
5. A process as claimed in claim 1, claim 2 or claim 3 in which the cellolignin is waste paper of low hemicellulose content.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE3040850A DE3040850C2 (en) | 1980-10-30 | 1980-10-30 | Process for the production of water-soluble saccharides from cellulose-containing material |
| DEP3040850.5 | 1980-10-30 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1181397A true CA1181397A (en) | 1985-01-22 |
Family
ID=6115523
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000389579A Expired CA1181397A (en) | 1980-10-30 | 1981-10-29 | Process for obtaining water-soluble saccharides from cellulose-containing material |
Country Status (14)
| Country | Link |
|---|---|
| EP (1) | EP0051237B1 (en) |
| JP (1) | JPS57105200A (en) |
| AT (1) | ATE26129T1 (en) |
| AU (1) | AU7694281A (en) |
| BR (1) | BR8107016A (en) |
| CA (1) | CA1181397A (en) |
| DD (1) | DD208173A5 (en) |
| DE (2) | DE3040850C2 (en) |
| DK (1) | DK478381A (en) |
| FI (1) | FI813370L (en) |
| NZ (1) | NZ198780A (en) |
| PH (1) | PH17341A (en) |
| PL (1) | PL233621A1 (en) |
| ZA (1) | ZA817493B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010124380A1 (en) * | 2009-04-30 | 2010-11-04 | Evegenetics Canada Inc. | Process and apparatus for recycling coated paper products |
| US20120042566A1 (en) * | 2009-04-30 | 2012-02-23 | Eve Research Inc. | Preparation of biofuels and other useful products such as 5-(hydroxymethyl)-furfural |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3142215A1 (en) * | 1981-10-24 | 1983-05-05 | Hoechst Ag, 6230 Frankfurt | "METHOD FOR DIGESTING CELLULOSE-CONTAINING MATERIAL WITH GAS-SHAPED FLUORINE" |
| DE3142214A1 (en) * | 1981-10-24 | 1983-05-05 | Hoechst Ag, 6230 Frankfurt | "METHOD FOR DIGESTING CELLULOSE-CONTAINING MATERIAL WITH GAS-SHAPED FLUORINE" |
| DE3142216A1 (en) * | 1981-10-24 | 1983-05-11 | Hoechst Ag, 6230 Frankfurt | METHOD FOR DIGESTING CELLULOSE-CONTAINING MATERIAL WITH GAS-SHAPED FLUORINE |
| DE3312450C2 (en) * | 1983-04-07 | 1985-02-07 | Knauth, Hans, Dipl.-Ing., 7758 Meersburg | Two-step process for the production of furfural and glucose from cellulose-containing substances by acid hydrolysis |
| FR2597872B1 (en) * | 1986-04-25 | 1988-11-18 | Beghin Say Sa | PROCESS FOR THE PREPARATION OF BRANCHED OLIGO- AND POLYOSIDES, PARTICULARLY FROM STARCH |
| RU2135510C1 (en) * | 1998-12-21 | 1999-08-27 | Общество с ограниченной ответственностью "ПлУГ" | Method and installation for processing larch wood |
| US6265037B1 (en) | 1999-04-16 | 2001-07-24 | Andersen Corporation | Polyolefin wood fiber composite |
| CA2818041C (en) * | 2010-11-25 | 2015-10-13 | Studiengesellschaft Kohle Mbh | Method for the acid-catalyzed depolymerization of cellulose |
| DE102016013620A1 (en) | 2016-11-15 | 2018-05-17 | Christine Apelt | Process for the material and energetic utilization of residues of sugarcane processing and arrangement for carrying out the process |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB271410A (en) * | 1926-05-20 | 1928-01-05 | Brevets Etrangers Lefranc Et C | Process for the hydrolysis of cellulosic substances |
| DE560535C (en) * | 1927-03-15 | 1932-10-05 | I G Farbenindustrie Akt Ges | Process for the conversion of polysaccharides |
| DE577764C (en) * | 1930-03-18 | 1933-06-03 | I G Farbenindustrie Akt Ges | Process for the conversion of polysaccharides |
| CH246473A (en) * | 1944-01-12 | 1947-01-15 | Scholler Heinrich Ing Dr | Process for the manufacture of sugar not intended primarily for human consumption. |
-
1980
- 1980-10-30 DE DE3040850A patent/DE3040850C2/en not_active Expired
-
1981
- 1981-10-24 AT AT81108878T patent/ATE26129T1/en not_active IP Right Cessation
- 1981-10-24 EP EP81108878A patent/EP0051237B1/en not_active Expired
- 1981-10-24 DE DE8181108878T patent/DE3176031D1/en not_active Expired
- 1981-10-28 NZ NZ198780A patent/NZ198780A/en unknown
- 1981-10-28 FI FI813370A patent/FI813370L/en not_active Application Discontinuation
- 1981-10-28 PH PH26410A patent/PH17341A/en unknown
- 1981-10-28 DD DD81234420A patent/DD208173A5/en not_active IP Right Cessation
- 1981-10-29 AU AU76942/81A patent/AU7694281A/en not_active Abandoned
- 1981-10-29 CA CA000389579A patent/CA1181397A/en not_active Expired
- 1981-10-29 DK DK478381A patent/DK478381A/en not_active Application Discontinuation
- 1981-10-29 JP JP56172177A patent/JPS57105200A/en active Pending
- 1981-10-29 BR BR8107016A patent/BR8107016A/en unknown
- 1981-10-29 PL PL23362181A patent/PL233621A1/xx unknown
- 1981-10-29 ZA ZA817493A patent/ZA817493B/en unknown
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010124380A1 (en) * | 2009-04-30 | 2010-11-04 | Evegenetics Canada Inc. | Process and apparatus for recycling coated paper products |
| US20120042566A1 (en) * | 2009-04-30 | 2012-02-23 | Eve Research Inc. | Preparation of biofuels and other useful products such as 5-(hydroxymethyl)-furfural |
| US8715462B2 (en) | 2009-04-30 | 2014-05-06 | Alexis Fosse Mackintosh | Process and apparatus for recycling coated paper products |
| US9683328B2 (en) | 2009-04-30 | 2017-06-20 | Eve Research Inc. | Preparation of biofuels and other useful products such as 5-(hydroxymethyl)-furfural |
Also Published As
| Publication number | Publication date |
|---|---|
| DE3040850C2 (en) | 1982-11-18 |
| AU7694281A (en) | 1982-05-06 |
| NZ198780A (en) | 1984-12-14 |
| BR8107016A (en) | 1982-07-13 |
| DK478381A (en) | 1982-05-01 |
| JPS57105200A (en) | 1982-06-30 |
| FI813370L (en) | 1982-05-01 |
| ATE26129T1 (en) | 1987-04-15 |
| PH17341A (en) | 1984-08-01 |
| DE3176031D1 (en) | 1987-04-30 |
| EP0051237B1 (en) | 1987-03-25 |
| DE3040850A1 (en) | 1982-05-13 |
| DD208173A5 (en) | 1984-03-28 |
| PL233621A1 (en) | 1982-06-07 |
| ZA817493B (en) | 1982-11-24 |
| EP0051237A1 (en) | 1982-05-12 |
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