DE2001768A1 - Compositions containing derivatives of >> hemicellulose << - Google Patents

Description

PATENT LAWYERS? Π ΓΜ 7 fi 8

DIPL-CHEM. DR. WERNER KOCH DR.-ING. RICHARD GLAWE

DIPL.-ING. KLAUS DELFS. DIPL-PHYS. DR. WALTER MOLL

HAMBURG MÖNCHEN

2000 Hamburg 52. Waltz «street 12 · Ruf 89 22 8000 Munich 22 ■ UebherrstraSe 20 · Call 22 6548

YOUR SIGN

REGARDS:

YOUR MESSAGE FROM OUR SIGN

P 55 ^ 5/70

e / t

HAMBURG

LINEN INDUSTRY RESEARCH ASSOCIATION, LAMBEG , LISBURN, CO ANTRIM, NORTHER IRELAND

Compositions containing derivatives of "hemicellulose".

The invention relates to compositions derived from "hemicellulose ^11, and methods for their preparation.

As used herein, "hemicellulose" is intended to include the polysaccharides and polyuronides of the type which make up the majority of the polymeric materials associated with cellulose, such as most natural cellulosic fibrous materials.

The present invention provides a composition that is substantially or wholly insoluble in water

009831/2012

-2-

and the "contains hemicellulose ¹¹ with metal or semi-metal ions incorporated therein.

Although the ions can only be ^{held or enclosed in the hemicellulose 11} , they preferably form a complex or form a salt therewith. Also, the composition is preferably in the form of a gel.

The composition according to the invention has numerous uses, mainly of the metal or semi-metal ions, which are incorporated into the hemicellulose depend. The composition has an important use as a heterogeneous catalyst for reactions such as hydrogenation, polymerization, degradation and oxidation, in particular where it has heretofore been difficult to support metal ions in a suitable and satisfactory manner. For such a use, the composition preferably contains "hemicellulose" with transition metal ions incorporated therein, such as chromium, manganese, molybdenum, cobalt, nickel, iron, platinum, palladium, Titanium or copper ions.

Another use of the composition is in agriculture and horticulture as a carrier for important trace elements for plant growth and for influencing flower colors. For these purposes, is one of the useful properties of the composition that the metal or Ilalbmetallionen are made temporarily insoluble and gradually duroh microbial effect and Feuohtig-

009836/2062

2001769

ability to be released from the composition rather than from the soil layer to which they are applied leached out, as is the case with most common remedies.

The composition may conveniently contain silica gel or alumina. Further, the composition and especially when it is intended for use as a catalyst, optionally be modified, for example, thermally, by subjecting them to temperatures above 20O ⁰ C. The product of such thermal modification will depend on the metal or semimetal ions and the environment, for example temperature and atmosphere, in which the composition is treated.

themselves
For example, the composition begins to decompose in air at −6O mm Hg at around 200 ° C. until the hemicellulose contained therein forms a carbon skeleton at around 500 to 600 ° C. that is stable up to comparatively high temperatures. When compositions containing silica gel or alumina are subjected to elevated temperatures, decomposition of the hemicellulose as the carbon skeleton forms creates pores in the silica gel or alumina, forming a porous structure with increased effective surface area and easily accessible, uniformly spaced reactive sites remains for catalytic and / or absorption purposes. It is also possible to obtain a gel structure by such a treatment which

009836/2082

has desired pore sizes for use in preferential or selective chemical processes.

The effect of the elevated temperatures on the metal or semi-metal ions is far less predictable and depends mainly on the type of metal or semimetal ion present. For example, if you have compositions which contain manganese or copper ions, subject to temperatures above 500 C, deliver them Carbon skeleton with manganese or Copper metal, while compositions containing chromium- or include molybdenum ions, which provide the corresponding oxide evenly applied.

It is possible in some cases where silica gel or alumina is included in the composition and where the metal or semi-metal ions combine with the carbon in the framework structure so formed To oxidize carbides, for example by exposing them to elevated temperatures under an oxidizing atmosphere subject to the corresponding metal or semimetal ions, or their oxides, in the silica gel or Alumina worn to leave behind.

Another aspect of thermal modification is the fact that the oxidation state of the metal ions introduced into some compositions is changed ν ν, if the compositions are subjected to elevated temperatures, which is generally shown by color changes,

0 098 3 6/2062

especially where there are transition metal ions, for example Chromium ions. This point of view is significant because metal ions are present in various oxidation states. levels are kept deposited in higher concentration and more evenly on supports such as silica gel and alumina than was previously possible.

The invention also provides a process for the preparation of the composition characterized by Steps: Addition of a metal or semi-metal salt that

is different from a simple alkali metal salt, to a hemicellulose solution made by dissolving hemicellulose in an alkaline solution and, if necessary, reducing the pH of the solution to Precipitation of the composition and subsequent separation of the precipitate from the overlying liquid.

The term simple alkali metal salt is to be understood as meaning a salt in which the cations alone Ions of alkali metals are and the anions are only non-metal radicals Contain, as in sodium and potassium chlorides as well as sodium and potassium nitrates. Salts, such as Kaliuraperman— ganate and potassium chromate, in which the anions contain metal radicals, do not fall under this designation and are in in fact particularly useful in the method of the invention.

Preferably the composition is filtered off, washed and dried. The drying takes place appropriately

-6-

009836/2062

by heating the filtered composition to a temperature of about 10O ⁰ C.

Said metal or semi-metal is preferably also salt added to the solution in dissolved form.

The lowering of the pH of the solution can be effected in any conventional manner, for example by adding an acid such as Hydrochloric acid, sulfuric acid or acetic acid is added or by passing an acidic gas such as carbon dioxide or sulfur dioxide through it.

In the textile, wood pulp and allied industries where natural cellulose-based fibers are used such substances are often chemically treated to remove impurities associated with cellulose are to be removed. Such chemical treatment includes often boiling the natural material in an alkaline solution, removing most of the impurities, including Hemicellulose, thereby facilitating its removal from the insoluble cellulose. If the The resulting alkaline solution is separated from the cellulose - it is generally discarded as a drain.

However, the high organic content of the effluent, the SiOH resulting mainly from the existing "hemicellulose," leads to the fact that it has a high factor for the biological oxygen demand, particularly where the natural material has a large amount of impurities as ■ it flax is the case where the factor can reach a value of 12,000 mg / l.

009836/2062

While these alkaline solutions and drains containing them have hitherto generally been considered a nuisance have been viewed and have raised problems because of their satisfactory removal, they are particularly useful as Hemicellulose Sources for the Present Invention. Even if this is not the main object of the invention, reduced the use of "hemicellulose" "those of these Sources has been obtained, the organic content and therefore the factor for the biological oxygen demand (B.O.i '. Factor = Biological Oxygen Demand factor), so that Difficult— ™ elimination can be reduced. It is emphasized, however, that "hemicellulose" from other sources works just as well. can be used for the present invention.

If desired, cheap sources can be used for that Metal or semi-metal salt solution can be used to obtain the composition, taking the drains from metal pickling equipment or ore leaching are particularly useful in this regard.

Compositions containing silica gel or aluminum oxide A are expediently prepared by adding sodium silicate or an aluminum salt prior to precipitation of the hemicellulose derivative, or alternatively, in the case of compositions containing silica gel, the hemicellulose / metal or semimetal mixture can be dissolved in sodium silicate after isolation and are subsequently precipitated by acidification together with silica gel.

-8th-

00983 67 2082

It has been found that the yield obtained can be increased in cases where the alkaline solution is acidified could by adding at least one crosslinking agent of those defined below before, during or after acidification of the solution Art added.

The type of crosslinking agent is defined as being reactive with the hydroxyl groups, the contained in the main or side chains of the heraicellulose molecule. For example, formaldehyde and are suitable Ethylene oxide as one such agent. The effectiveness of the crosslinking agent can be increased by heating the solution its addition to be improved.

In a first preferred embodiment from this aspect of the invention, the pH is adjusted to the range from k to 6 and then a solution of the crosslinking agent is added thereto. Dna · .: χ. The pH is reduced in the range from 1.5 to 2.5 in order to bring about precipitation.

In a second preferred embodiment under In this aspect of the invention, a solution of the crosslinking agent initially becomes the alkaline solution added, after which the pH of the solution is brought within the range of 1.5 to 2.5.

The crosslinking agent can, if desired, be used where silica gel or aluminum oxide is ^{to be precipitated together with the hemicellulose 11.} Again, an increased yield is obtained.

-9-

009836/2082

The mechanism by which the crosslinking agent to achieve greater yields compared with methods where no such agent is used, _{erinöglicht}} is not fully understood. However, it is assumed that the effective molecular weight of the ^M hemicellulose ^M - * polymers or fragments thereof which are present in the alkaline solution is a determining factor in the precipitation process, and it is assumed that the means for crosslinking the polymers or fragments, whereby the effective molecular weight to a value above that for the Jj

Precipitation critical is increased. It is believed that this cross-linking effect is particularly important where the "hack-cellulose" or a hemicellulosehaltiges material in the alkaline solution has been cooked and the "hemicellulose ⁿ ~ polymer chains to some extent degraded as a result of such treatment or torn apart (in generally including detachment of the xylan side chains), so that in effect their molecular weight is reduced below the value critical for precipitation.

In addition to the improved yield, the use of the crosslinking agent results in the following further advantages parts achieved:

a) the precipitate can be filtered off more quickly

b) the dried precipitate can be converted better into powder form and

-10-

009836/2082

c) the product has an enlarged effective surface significant factor - where it is for catalytic or To be used for absorption purposes.

It also became "hemicellulose" in amniotic fluid dissolved and a gel from it by adding a transition metal salt pleases.

Preferably the "hemicellulose" is in excess Dissolved ammonium hydroxide and the excess before the addition of the Transition metal salt removed, for example by boiling or evaporation.

In the event that the "hemicellulose ^{11 is} discolored and this discoloration goes into the hemicellulose / ammonium hydroxide solution, the solution can be decolorized by activated charcoal, the charcoal then being removed, for example by filtration, before the transition metal salt is added.

After precipitation, the gel can be isolated and then dried, for example by heating to 80 100 ^° C.

The gel can expediently be held on a carrier for this purpose, for example on silica gel, aluminum oxide, pumice stone, kieselguhr and asbestos. This can be done by impregnating the carrier by heating at about 100 - dried 200 ° C, in the presence of a dehydrating agent such as phosphorus pentoxide, cools and danaoh the same to the "hemicellulose ¹¹ /

009836/2062

Ammonium hydroxide solution is added, so that at least a part the solution is taken up, whereupon a solution of the transition metal salt is added.

It can again cause a modification of the gel will. Transition metal salts which have been found to be particularly useful in this regard of the invention include Chromium sulfate, cobalt chloride, manganese sulfate, copper sulphate, nickel sulphate and ferrous sulphate,

To assess the catalytic activity of the compositions provided by the present invention, wu <t liquid drains, which have a oxidizable organic overall M halt, treated by a stream of oxygen or sauerstoffhaltigera gas through the outlet in the presence of a composition according to the invention eggs sent or let flow.

Preferably, for economic reasons, air is used as the oxygen-containing gas, the Air using known ventilation techniques the drain is directed.

The composition can be held in the flow path of the oxygen or oxygen-containing gas by carrier means or it can be suspended in the drain, preferably in powder form, and can be allowed to diffuse freely in the flow path of the oxidizing gas, for example by a fluidized bed technique.

-12-

009836/206 2

Compositions are preferably used in this method of treatment used that include transition metal ions, or those compositions which have been modified, for example by the aforementioned thermal process.

In order to obtain a more effective oxidation of the runoff, the runoff is preferably treated at elevated temperatures, i.e. where the drain is liquid or contains liquid that has been heated prior to disposal, the Treatment is preferably carried out while the effluent is still at an elevated temperature. However, it must be observed that the drain alone or in addition to the treatment process can be heated where it is economically feasible.

The invention is illustrated in more detail by the following examples.
example 1

To 1 liter of effluent from a green flax alkaline cooker was added 100 ml of 3% potassium permangana solution, followed by 15 ml of 50% sulfuric acid to lower the pH to 2, forming a black gelatinous precipitate.
Example 2

To 1 liter of a drain similar to that used in Example 1 was added 100 ml of a 6% potassium permanganate solution added, then 7 ml of a 50% Sohwefel-

009836/2062

ORiGiNAL INSPECTED

acid to reduce the pH to 5 at which point a black gelatinous precipitate formed.
Example 3

100 ml of a 30% - « added potassium permanganate solution. A black gel formed without the need for acidification.

The products of Examples 1 to 3 were filtered off, washed and dried) to give glossy black cells of "Hemicellulose ¹ * with manganese ions incorporated therein. Gravimetric analysis showed a manganese content of about kO%,
Example k

The drain from a digester was treated by adding a solution of ferrous sulfate. Imagine gelatinous precipitate which was filtered off and dried. This gel mainly contained "hemicellulose" with iron (II) ions introduced therein, but contained basic hydroxides of iron as an impurity. However, despite the contamination, the gel was acceptable for use as an iron supplier in agriculture and horticulture. ™

Example 5

The drain from an alkaline digester of green flax fiber was treated by adding a solution of calcium chloride. Immediate gel formation was observed and additional calcium chloride was added until no further gel was formed. The gel was then removed from the supernatant

009836/2062

- Ik -

Filtered off liquid, washed several times with water, dried and crushed to form small chunks. Example 6

5 g of dried "IIemicellulose" gel were added to 800 ml of a 1% sodium carbonate solution with stirring until it was completely dissolved. 3 g of potassium chromate was dissolved in 5 ml of water and the resulting solution was ^{added to the alkaline "Hemicellulose 11"} solution with thorough stirring. 10 η sulfuric acid was added to the combined solution until complete precipitation was effected . The precipitated gel became then separated from the supernatant liquid and washed, filtered and dried. Example 7

To 10 liters of the drain created by boiling green flax fiber was added 200 ml of concentrated sulfuric acid, followed by 1 liter of 40% formaldehyde (crosslinking agent) and the mixture was kept boiling for 2 hours. Sodium molybdate (50g) was added and cooking continued for an additional hour. A molybdenum / hemicellulose coraplex was precipitated by adding 100 ml of concentrated sulfuric acid. The precipitate was filtered off, washed and dried to give 120 g of a yellowish green, light solid.

Half of the precipitate was dissolved in 300 ml of sodium silicate (50 ⁰ Tw) and a cogel of silica gel / molybdenum cellulose was precipitated by adding 50 ml of 12% strength sulfuric acid

009836/2062

added to bring the pH to 1.5. This was filtered off, washed and dried to give 300 g of solid material to surrender.

This latter material was thermally ^{modified at 500 °} C. to give finely precipitated molybdenum oxide throughout the silica gel.
Example 8

To one liter of a drain similar to that used in Examples 1 to 3, 3 ml of concentrated sulfuric acid were added, then 50 ml of sodium silicate (50 ⁰ Tw) and 300 ml of 10% w / v. Potash permanganate. After stirring well, 50 ml of 10% w / v sulfuric acid was added to cause gelation. The gel was aged for 5 hours, then slurried with water, filtered and washed. After drying at 90 ° C., the gel was washed again and dried again. The yield was 75 g of a black gel of crystalline appearance which had an effective surface area of 100-200 m / g and a manganese content of 15%.

Half of this gel was thermally modified by heating it to 500 ^° C. in a muffle furnace for 3 hours. The catalytic effectiveness of the unmodified and thermally modified product of this example was assessed by the method given in example 11. Example 9

There were 40 g of hemicellulose in 2 liters of distilled Slurried water and added enough ammonia to

009836/2082 '" ^l6 "

to dissolve the suspended hemicellulose. It became excess Boiled ammonia and added decolorizing charcoal to the boiling solution. The solution was filtered and divided into portions of 250 nil each, each treated as follows:

a. 100 ml of 5% copper sulfate was added to a green ~ it to create translucent gel. After washing and drying, thermogravimetric analysis gave a copper content of 13.5%.

b. 60 ml of 5% cobalt sulfate was added to give a pink, translucent gel.

c. 90 ml of 5% manganese chloride was added to give a to produce white translucent gel.

d. 70 ml of 5% chromium sulfate were added to produce a blue, translucent gel. This had a chromium content of 12.5 ^o h »

e. 95 ml of 55% nickel sulfate was added to give a generate green, translucent gel.

f. 50 ml of 5% ferrous sulfate was added to produce an amber translucent gel. This contained 12 % iron.

Example 10

100-200 mesh silica gel was added to 250 ml of a solution of hemicellulose in ammonia until all of the ilemicellulose solution was absorbed onto the silica gel. There were 10'J irI 10% chromium sulfate added and that

009836/2082

resulting blue, supported gel was washed and dried to produce a clearly homogeneous green gel. Thermal modification produced the following color changes,

20O ⁰ C - apple green

300 ⁰ C - yellowish brown 500 ⁰ C - bright yellow 600 ° C - orange

700 ⁰ C - pea green

1000 ⁰ C - dark green ^

Example 11

Three batches of drainage, which came from a flax cooker and had different BOD values, were isolated. The first was treated for 5 hours by bubbling air through it in the presence of the unmodified product of Example (Catalyst A); the other two were treated in a similar manner for 3 hours, firstly in the presence of catalyst A and secondly in the presence of the thermally modified product of the Λ

Example 8 (Catalyst B).

The results of these treatments are shown in the following table:

-18-

009836/2082

catalyst
structure Treatment—
Time
hours ι pH Drain final
tiger
BOD Fast
speed of
BOD Vermin
change A. 11th initial
BOD 7,800 tfg./l./h. A.
B. 3
3 11th
11 11,600 2,000
1,300 760 A.
B. 3
3 11th
11th 2,200
2,200 500
350 66
133 650
650 50
100

Treatment of the effluent simply by bubbling air through it in the absence of catalyst A or B did not affect the corresponding BOD values.

It must be emphasized that the invention is not limited to the above examples, rather they are manifold Modifications, which are readily apparent to the person skilled in the art, are possible without departing from the scope of what the invention is based on Thought as defined in the claims to exceed.

For example, compositions can be prepared which contain semimetal ions and metal ions other than those described in the preceding examples.

009836/2062

-19-

Furthermore, the compositions can be pelletized or put into tablet form »If the procedure a heniieellulose / amraoniumhydroxyd-Losmig includes, The compositions can easily be converted into fiber or Filinform by extruding the solution into a bath of the Transition metal salt solution can be processed.

- 20 -

009836/2062

Claims (1)

PATENT CLAIMS 1)) Composition, substantially or entirely is insoluble in water and the "hemicellulose" is in it Introduced metal or semi-metal ions contains. 2) Composition according to claim 1, characterized in that said ions are carried or entrapped ^{in the "hemicellulose 11".} 3) Composition according to claim 1, characterized in that said ions with the "hemicellulose" form a complex or a salt. h) Composition according to one of Claims 1 to 3 "characterized in that g" = ¹ "indicates that it is in the form of a gel, 5) Composition according to any one of the preceding claims, characterized in that said ions those of a transition metal. 6) Composition according to claim 5, characterized in that the transition metal is selected from the group consisting of chromium, manganese, molybdenum, cobalt, nickel, iron, platinum, palladium, titanium and copper . 7) Composition according to one of the preceding claims, characterized in that it contains silica gel or aluminum oxides ( A \ ril t. üÖ9836 / 20f2 200: 768 8) A composition according to any one of the preceding claims, characterized in that it is incdiiisiert by being subjected to temperatures above 200 G. 9) Composition according to claim S, characterized in that it is modified by being subjected to a temperature in the range 500 to 600 ° C. 10) Process for the preparation of a composition according to claim 1, characterized by the steps: adding a metal or semimetal salt, which is different from a simple alkali metal salt, to a solution of "hemicellulose ¹¹ , which is obtained by dissolving" hemicellulose ¹ * in an alkaline Solution has been prepared, and if necessary, reducing the pH of the solution to precipitate the composition and then separating the precipitate from the overlying liquid. 11) Method according to claim 10, characterized in that the precipitate is filtered, washed and dried will. 12) The method according to Anspruoh il, characterized in that the precipitate is dried by heating it to a temperature of about 100 ⁰ C. -22- 009836/2062 13) Method according to one of claims 10 to 12, characterized in that the metal or semimetal salt is added to the solution in the form of a solution. 1 ^ t) method according to one of claims 10 to 13, characterized in that the "hemicellulose" solution is the solution that results from an alkaline cooker of natural cellulosic fibers or is a drain containing such solution. 15) Method according to claim lh, characterized in that the ^rt hemicellulose "solution is the solution that results from the alkaline kettle boiling of flax or is a drain that contains such a solution. 16) Method according to claim 13, characterized in that the solution of the metal or semimetal salt of Drain from a metal pickling plant or ore leaching plant. 17) Method according to one of claims 10 to 16, characterized in that sodium silicate or an aluminum salt is added to the solution of "hemicellulose ¹¹ " and is precipitated together with the "hemicellulose" as silica gel or as aluminum hydroxide. 18) A method according to any one of claims 10 to 16, data duroh in that the precipitate after separation is achieved in a Natriumsilikatlbsung and then 009836/2062 to sarans with the hatriu by acidification; r: sili iccit g? xrUlt becomes, taking the sodium silicate as silica gel 19) Method according to one of claims 10 to 16, characterized characterized in that said "hemicellulose" «solution is acidified and where before, during or nash clit: or Acidification exposes at least one crosslinking agent will. 20) The method according to claim 19 »characterized in that the pH of the solution is adjusted to the range h to 6, a solution of the crosslinking agent is added and the pH is then brought to the range 1.5 to 2.5 for precipitation to effect 21) Method according to claim 19 %, characterized in that a solution of the crosslinking agent »is added to the" ¹ * hemicellulose solution, then the pH of the solution is brought into the range from 1.5 to 2.5 in order to bring about precipitation . 22) Method according to one of claims 19 to 21, characterized in that said crosslinking agent is formaldehyde or ethylene oxide. 23) Method according to one of claims 10 to 13, characterized in that the "hemicellulose ^w solution is prepared by" hemicellulose ¹¹ in ammonium hydroxide 009836/2082 - 2h - solution dissolves, the precipitation by the addition of a transition metal salt solution is effected. 2k) Method according to claim 23, characterized in that the "hemicellulose" is dissolved in excess ammonium hydroxide, the excess being removed before the transition metal salt solution is added. 25) Method according to claim 23 or 24, characterized in that that any discoloration of said "hemicellulose" - Solution is eliminated by using activated carbon. 26) Method according to one of claims 23 to 25, characterized in that the precipitate on a Carrier material such as silica gel, aluminum oxide, pumice stone, kieselguhr or asbestos is formed, the carrier material is dried by heating to 100-200 ° C, is cooled in the presence of a dehydrating agent and added to the "hemicellulose" solution so that at least a portion of the solution is absorbed, after which the transition metal salt solution is added. 27) Method according to one of claims 23 to 26, characterized in that the transition metal salt solution a solution of one or more salts of the group chromium sulfate, cobalt chloride, manganese sulfate, copper sulfate, Nickel sulfate and iron (II) sulfate is. -25- 009836/2062 28) Method according to one of claims 23 to 27, characterized characterized in that the precipitate is thermally modified after separation. 29) Use of a composition according to any one of claims 1 to 9 as a catalyst for a chemical Process. 30) Process for the treatment of runoffs which have an oxidizable organic content, characterized in that that a stream of oxygen or oxygen-containing gas in the presence of a composition according to one of the Claims 1 to 9 hindurci ^ sends or lets flow through. 31) Method according to claim 30 »characterized in that that said oxygen-containing gas is air. 32) Method according to claim 30 or 31 »characterized in that said composition by carrier means in said flow path of said oxygen or oxygen-containing Gas is held or is in powder form and is allowed to diffuse freely in said flow path. 33) means for horticulture or agriculture, characterized in that it is a composition according to any one of claims 1 to 9 contains. 009836/2062