CS225129B2 - The production of alkalicellulose - Google Patents

Abstract

A process for the preparation of alkali cellulose by reacting steeping lye and cellulose pulp manufactured by alkali cooking without prehydrolysation or by acid cooking without alkali extraction, and by adding to the cellulose pulp, the steeping lye or the alkali cellulose at least one organic compound which is an alcohol, an ester, an ether, a ketone, an amine, an acid or the salt of such an acid, an imine or an aliphatic hydrocarbon of at least four carbon atoms.

Description

The invention relates to a process for producing alkelicellulose from a cellulose-containing feedstock.

In the preparation of cellulose-containing fibers and films containing cellulose containing regenerated cellulose or cellulose ethers such as carboxymethylcellulose, the first stage of production is usually the production of alkelicellulose.

The method of manufacture by known methods is essentially as follows:

the cellulose pulp used as raw material is treated with a sodium hydroxide solution (NaOH) of sufficient concentration to convert the cellulose into alkali cellulose. This process or dipping is carried out either by dipping the cellulose leaves into a NaOH solution or by forming a slurry of cellulose in a NaOH solution such that the cellulose content of the slurry or slurry is 5%. The concentration of the NaOH solution used in the steeping is usually in the range of 17-22% FiaOR.

Excess NaOH solution is removed by compression to give an alkalicellulose in which the NaOH content is 15 to 17% and the alkelicellulose content is 30 to 35%. The alkalicellulose obtained is flocculated or chewed. ·

Alkalicellulose is aged by exposure to atmospheric oxygen at a temperature between 20 ° C and 60 ° C. During ripening, the cellulose molecule chains tear in such a way that the average size of the molecules decreases · The average size of the molecules required is a determinant of temperature fluctuations and aging duration · Reaction may be accelerated by the use of catalysts such as cobalt or manganese salts

Alternatively, it is possible to add to the shredded cellulose only a certain amount of NaOH solution that is required to obtain the desired alkelicellulose composition directly.

Typical cellulose-containing raw materials to be used are bleached sulphite pulp or pre-hydrolyzed sulphate pulp. Especially in the production of cellulose xenthogenate or viscose solutions from alkelicellulose, the high quality requirements for the cellulose pulp used are high. In the preparation of viscose, it is of particular importance that the cellulose xanthogenate prepared from alkelicellulose is as soluble as possible to avoid viscose filtration problems. This requirement is achieved only for pulps specially manufactured for the viscose industry or chemical pulps, which are bull sulphite pulp or pre-hydrolysed sulphate pulp, which have an alpha-cellulose content usually greater than 90%.

Other pulps, especially kraft pulp for the papermaking industry, are not used in the viscose industry, since in particular papermaking kraft pulp yields a viscose which is particularly poorly filterable, contains non-swellable gels and insoluble fibrous particles.

In the case of kraft pulp, this is due to the fact that in alkaline cooking an inadequate amount of structurally separated regions in the walls of the cellulose fibers is formed to initiate the formation of alkelicellulose. In acid cooking As in the case of sulphite cooking or acid prehydrolysis, on the other hand, these regions are formed by removing hemicellulose due to hydrolysis.

The pulp industry that used the sulfin process (acid cooking) to a greater extent than the sulphate process (alkaline cooking) is increasingly switching to the sulphate process.

No new sulphite pulp factories are built, old sulphite pulp factories are closed or converted to sulphate process. The reasons are both environmental and economic.

In the production of sulphite pulp and a high content of alpha-cellulose or in particular pre-hydrolyzed sulphate pulp, part of the alpha-cellulose is lost, resulting in a lower pulp yield. This means that the price of the finished cellulose increases and increases proportionally with the alpha-cellulose content. If the alpha-cellulose content increases by 1%, the yield decreases by about 3%. The current price difference is that chemical pulp is approximately 30% more expensive than normal pulp used in the paper industry. For this reason, it would be advantageous to use, for example, paper kraft pulp in the production of alkalicellulose if there were no technical difficulties.

Kraft pulp would also benefit from low resin content and low polydispersity, which is important with respect to viscose fiber quality, especially in terms of toughness.

According to Finnish patents Nos. 41,543 and 41,544, filterable viscose can also be produced by so-called double dipping from low-quality pulps, such as normal kraft pulp. In the process disclosed in these patents, alkali cellulose is soaked again after ripening. However, problems arise in comparison with the normal process, since double the number of dipping presses is required, thus increasing investment and operating costs.

By using various additives in the steeping liquor, a slight improvement in the alkali cellulose reactivity is achieved. The use of various steeping liquor additives is known and to some extent industrialized. These additives are used, for example, to disperse pulp resins, to increase pulpability or to increase sulphidization (xanthogenesis). However, chemical pulp is always used for the preparation of alkali cellulose and the amount of additives used is small.

U.S. Pat. No. 3,506,754 relates to a process for the preparation of viscose using carbon disulphide compounds and certain additives for the xanthation of alkali cellulose. U.S. Pat. No. 2,536,334 relates to a sodium zincate mercerization liquor which acts together with organic substances as a cellulose solvent. French Patent No. 2,085,575 relates to the use of certain viscose additives to improve the textile properties of fibers prepared by viscose spinning. U.S. Pat. No. 2,680,737 relates to the use of some organic solvents in place of water or simultaneously with water in merceration. U.S. Pat. No. 2,663,704 discloses the addition of ethylenediaminetetraacetic acid as an additive to the mercerization liquor as sequestering agent and the alkyl alcohol sulfate as a wetting agent. Both of these substances must be used together. U.S. Pat. No. 2,393,817 describes the use of a compound of the formula

A / C ₂ H ₄ O / _n-1 CH ₂ CH ₂ B.

However, the addition of alkali cellulose steeping agents has not been described.

However, it has now surprisingly been found that by using a certain amount of steeping additives, the alkalinity of the alkali cellulose can be increased to such an extent that even by dipping the kraft paper pulp, sufficient reactive alkali cellulose can be obtained, for example for viscose production.

It is therefore an object of the present invention to realize a process in which the raw material base of the viscose industry could be converted from expensive, specifically purified chemical pulp to ordinary paper pulp, which is a completely different raw material from chemical pulp.

Accordingly, the present invention provides a process for producing alkali cellulose from a cellulose-containing feedstock obtained by an alkaline batch without pre-hydrolysis and / or an acidic batch without alkaline extraction by reacting the feedstock with a steeping liquor. at least one organic compound selected from the group consisting of alcohol, ester, ketone, amine, acid is added to the alkali cellulose

225129 4 containing not more than 4 carboxyl groups per molecule or its sodium salt, imine or aliphatic hydrocarbon having at least 4 carbon atoms ·

The organic compounds added in the process of the invention typically contain a polyoxyethylene group, a polyoxypropylene group, or at least one hydrophobic, for example an aliphatic group having at least 3 carbon atoms, and at least one hydrophilic group such as a hydroxyl group, an ether oxygen group, or ketone groups. The active ingredients are simple hydrocarbons.

Examples of suitable organic additives in the process according to the invention are:

1 · Lecithin:

Lecithin own or phosphatidylcholine (20%)

ΟΗ, -0-R · L ^and

CH ₂ -OR ₂

CH ₂ -O-P 2 -O-CH ₂ -CH ₂ N ⁺ (CH ₃ ) ₃ , both R 1 and R ₂ are linoleic acid and oleic acid ^(C 17 ^H 31-33 ^CO phosphatidylethanolemin * phosphoinositides sugars | sterols triglycerides (15%), (20%), (10%), (about 35%).

2. но (с ₂ н ₄ о) _х (с ₃ н ₆ о) _у (c ₂ h ₄ o) _from h, who x, у sz, and also x + z is a maximum of 50 ·

3. R- (c ₂ H ₄ o) _x (c ₃ H ₆ o) _y (c ₂ H ₄ o) _z H, where x, у and _z are As above,

R = a) Rj-O- fatty alcohol, eg Rj ^and we rlvyl, lauryl, stearyl, oleyl etc.

alkylphenol, e.g., R ₂ = nonyl

(c) polyhydric alcohol, eg βorbito1

where x, у and z are as defined above,

R * alkyl, axyl or alkylaryl such as fatty amine, eg ethoxylate derivatives myristyl, lauryl, stearyl, oleyl etc. · amines · methylbutylketone butanol, primary and secondary amyl alcohols and alcohols higher than hexyl alcohol 8 octyl alcohols

6. ан ₃ -си ₂ -сн ₂ -сн ₂ -сн ₂ -он ch ₃ -h-ch ₂ -ch ₂ -oh ^CH 3

OH

CH ₃ -CH ₂ -CH-CH ₂ -CH ₃

7.

piperidine

10.

11.

<{H ₂ -ch ₂ -o-ch ₂

OH

various isomers

7 ^H 2 -f ^H 2

OH OC ₂ H ₅

_{And the} CH -CH -0-CH-CH _{of about} -0 - OH _{on the} CH | ^ 2 22 2 | 2

OH OH

13. с ₃ н ₇ -о-с ₃ н ₇ diethylene glycol monobutyl ether petroleum ether boiling range 100 to 120 ° C

14. <CH ₂ ⁰⁾ x psraforaaldehyde (= polyoxymethylene)

15 Dec CH-CH-CH ₀ and ³ and ² OH OH CH.-CH _D -CH ² _O ^{2 2} 1 ² OH OH propenddoly 16. R.NHg e.g. stearyl or cyclohexylamines 17. hexendiemine 18. C ^ H ^ COONe sodium stearate 19 Dec NaOOC4H3COONa sodium pimeline acid 20 May CH ₂ -O ₃ CCl ₁₇ H ₃₃

glycerol trioleate

CH-OCC-C.-H-- | 17 33 ch ₂ cOCOCC ₁₇ h ₃₃ (C ₁₂ h ₂₅ -n

) with ₄ laurylpyridinium sulfate

R, JH.COOR8 SO4 To the sodium salt of sullonated alkyl esters

Of these additives, lrcithin has proven to be the most preferred.

The Lee Cthin, its yield, the pure phosphatite or its derivative are preferably added in an amount of 0.01 to 20% by weight of the alpha-cellulose, while the organic ethers, esters, ketones, alcohols and / or pyridine derivatives are added depending on their quality or quantity. 0.1 to 100% of the amount of alpha-cellulose.

In addition to this discovery, it has also been surprisingly noted that there is a higher effect that said substances on the alkali cellulose oeakakiti, and this can also be utilized when the chemical pulp is a raw material, so that for example viscose production can be reduced. % to about 30% alpha-cellulose and a lower content of NaOH in the viscose than usual can be used.

The invention is further described in more detail by way of examples.

In the exemplary embodiments, the filterable or KW value is not a standardized measurement, but its. the size depends on the given paoameetes. The fitOovatelnossi values can be grouped as follows:

KW value FilOoovatelnltt 0 to 50 excellent 50 to 100 Good 100 to 150 average 150 to 300 bad 300 to 800 very poor > 800 n

Example 1

Normal bleached boron sulfate pulp, used in the paper industry and having an alpha-cellulose content of about 87%, was soaked as a 4% suspension in a steeping liquor with a concentration of 225 g NaOH per liter, at 35 ° C for 30 minutes. The liquor contained 10 g / liter, i.e. 25% by weight, compared to alpha-cellulose, fatty alcohol alkylene oxide, an ingredient known under the trademark Marlox FK 64. This ingredient is manufactured by Ghernische Werke Stick. AG.

An alkali cellulose mass was produced from the alkali cellulose suspension which was compressed in a molding ratio of 3.2. The mildly pulped alkelicellulose was aged for 18 hours at + 40 ° C and xentogenised for 2 hours at 35 ° C with carbon disulphide at 35% alpha cellulose, then dissolved to a viscose containing 5.3% NaOH and 13. 2% cellulose and viscosity determined by the falling bead method and a value of 48 seconds was found. The filter light was not the KW viscose value of 49.

In the same way, a viscose control sample was prepared but without the addition of Mealox FK 64 and a KW value of 2,778 was obtained.

Example 2

The viscose was prepared in the same manner as in Example 1 _, but instead of Merlox FK 64, the steeping liquor contained 10 g / liter, i.e. 25% alpha cellulose, polypropylene glycol with an average mioecular content of 400 produced by Shell Chemicel Co.. The viscose contained 5.2% NeOH and 9.6% cellulose and the falling bead viscosity was 68 seconds. KW viscosity was 52.

Example 3

Viscose was prepared in the same manner as in Example 1, but instead of Marlox FK 64, the steeping liquor contained 10 g / liter, i.e., 25%, less alpha-cellulose, diethylene glycol if butyl ether. _The viscose contained 5% NeOH and 9.8% cellulose and its viscosity, determined by the droplet bead method, was 57 seconds. KW value of viscose was 51.

Example 4

The viscose was prepared in the same manner as in Example 1, but instead of Marlox FK 64 the steeping liquor contained 10 g, i.e. 25% by weight of alpha-cellulose, of a mixture of secondary and secondary isoolers containing about 60% pentanol and about 36% penetrant. The viscose contained 5.3% NaOH and 9.9% cellulose with a viscosity determined by the bead-spinning method of 60 seconds. KW viscosity was 53.

Pííladd .. '

Viscose was treated in the same manner as in Example 1, but instead of Marlox FK 64, the liquor contained 10 g / liter, i.e. 25% of alpha-cellulose, aliphatic hydrocarbons boiling between 100-120 ° C. Viscose contained

5.2% NaOH and 9.7% cellulose with an unmeasured viscosity of the droplet bead was 76 seconds. KW viscosity was 75.

Example 6

The viscose was prepared in the same manner as in Example 1, but instead of the M 64 Lox FK 64, the steeping liquor contained 10 g / liter, i.e. 25 wt% elf-cellulose, piperidinium. The viscose contained 5.4% NaOH and 9.5% cellulose, and its determination by falling bead was seconds. The KW value of the viscose was 69.

Example 7

The tulle viscose was prepared in the same manner as in Example 1, but instead of Marlox FK 64 the steeping liquor contained 10 g, i.e. 25% by weight of alpha-cellulose, a polyethylene oxide / polypropylene oxide blend known under the Genapol PF 10 trademark manufactured by Farbwerke Hoechht AG. The viscose contained 5.1% NaOH and 9.8% cellulose and the viscosity determined by the flowing bead method was 42 seconds. KW viscose value was 37.

EXAMPLE 8

Viscose nape prepared steOtyo manner as in Example 1 but instead Merloxu FK 64 soaking liquors contained 10 glitters, it is 25% hmotnotti ELFRA-cellulose ethoxyloveného fatty amine known under the trade name Berol VLSC 32 and manufactured by f ^rm ^ ou Berol Kemi AB . The viscose contained 4.8% NaOH and 9.8% cellulose, although the droplet viscosity was 47 seconds. KW viscosity was 61.

Example 9

Viscose was prepared in the same manner as in Example 1, but instead of Marlox FK 64, the steeping liquor contained 0.2 glitre, i.e. 0.50% hootnooti of elfr-cellulose, an ethoxylated oleyleoin known under the trade name Genrnoin 0-020 a. produced by Farbwerke Hochst AG. The viscose contained 5.4% NaOH and 9.6% cellulose, the viscosity determined by the falling bead being 57 seconds. KW viscosity was 50.

EXAMPLE 10

Viscose was .připravena same manner as in Example 1 but instead Merloxu FK 64 Mai ^Affairs liquor contained 10 glitters, it is 25% hnoonoosi al ^f ^ rc role sodium ^é SOM sulfone rlkylesteru known under the trade name Berol VMA-478 manufactured e fimou Berol Kemi AB. The viscose contained 5.2% NaOH and 9.7% cellulose and the pellet bead viscosity was 43 seconds. - KW tulle viscosity 19.

See Example 11

Viscose nape prepared in the same manner as in Example 1 but instead Marlox FK 64 soaking liquors contain 1 10 glKr, i.e. 25% w ELFRA-cellulose rlkyleoooiddjkylfenolu, additives known under the tradename Marlox NP 109 E manufactured Irma Chemische Werke HUTOU A ^G. The viscose contained 5.3% ^N and ^OH b °, 4% cellulose ^{Y, P} RICE determined ^by viscosity pardjící the neck bead 46 seconds. KW viscosity was 59.

Píkl a d 12

Tulle viscose prepared in the same manner as in Example 1, but instead of Marlox FK 64, the steeping liquor contained 0.1 glitre, i.e. 0.25% of elf-cellulose, technical soya lecithin with a 35% fat content. The viscose contained 5.0% NaOH and 9.5% cellulose and had a falling ball viscosity of 23 seconds. KW tulle viscosity 47.

The viscose has been prepared in the same way, but without the addition of lecithin, which has a KW value of 2,000.

EXAMPLE 13

Of the non-white bleached birch kraft pulp used in the paper industry, with a cellulose content of about 87%, tulle viscose in the same manner as in Example 1, rle instead of Merlox FK 64 contained a steeping liquor of 10 g / liter, i.e. 25% alpha cellulose, methyl isobutyl ketone. The viscose contained 5.1% NaOH and 9.4% cellulose, the viscosity determined by falling bead was 20 seconds. KW viscosity was 60.

Control viscose was prepared in the same manner without addition of methyl isobutyl ketone and had a KW value of 1,024.

Example 14

Viscose was prepared in the same manner as in Example 13, but instead of methylisobutyl ketone, the steeping liquor contained 10 g / liter, i.e. 25% by weight alpha-cellulose, of a technical mixture of primary amyl alcohol isomers manufactured by Union Carbide Chemicals Co containing approximately 60% pentenol-1 and 40 % 2- and 3-methylbutanol-1. The viscose contained 4.5% NaOH and 9.14% cellulose with a droplet viscosity of 13 seconds. KW viscosity was 49.

Example 15

Normal bleached boron sulphate pulp, used in the paper industry with an alpha-cellulose content of approximately 87% by weight soaked as a 4% suspension in a steeping liquor of 225 g NaOH / liter, a hemicellulose content of 32 g per liter, at 55 ° C for 30 minutes. The steeping liquor contained 0.2 g per liter, i.e. 0.50% by weight of industrial soya lecithin alpha-cellulose, from which the fat contained was removed by acetone extraction. Alkalicellulose was compressed, aged and xanthogenized in the same manner as in Example 1. The viscose contained 5.3% NaOH and 9.6% cellulose, with a droplet viscosity of 37 seconds. KW viscosity was 82.

Example 16

The sulphite chemical pulp of coniferous wood was soaked in the form of a 4% suspension after a period of 10 minutes in a steeping liquor at a concentration of 225 g NaOH per liter at 25 ° C. The soaking liquor contained 0.1 g per liter, i.e. 0.25% by weight of alpha-cellulose, technical soya lecithin.

Alkalicellulose was prepared from the suspension in the same manner as in Example 1. After maturation, alkalicellulose was subjected to carbon disulfide xanthation in an amount of 25% by weight of alpha-cellulose and the xanthate obtained was dissolved to a viscose containing 5.1% NaOH and 9.6% cellulose. the falling ball viscosity was 60 seconds. KW viscose value 58.

The control viscose was prepared in the same manner, but without the addition of lecithin in the steeping liquor and the KW value obtained was 283.

Claims (4)

Process for the production of alkalicellulose from a cellulose-containing feedstock obtained by an alkaline batch without pre-hydrolysis and / or an acidic batch without alkaline extraction, by reacting the feedstock 8 with a steeping liquor, characterized by adding at least the cellulose-containing feedstock, the steeping liquor and / or one organic compound selected from the group consisting of an alcohol, an ester, a ketone, an amine, an acid containing up to 4 carboxyl groups per molecule, or a sodium salt thereof, an imine or an aliphatic hydrocarbon having at least 4 carbon atoms. 2. A process according to claim 1, wherein 0.1 to 100% by weight of alpha cellulose, organic ester, ketone, amine, acid or its sodium salt and / or pyridine derivative are added. 3. A process according to claim 1, wherein 0.01 to 20% by weight of alpha cellulose of phosphatidylcholine, phosphatidylethanolemine, phosphoinositide, sugar, sterol, fatty acid, triglyceride or a mixture thereof, such as lecithin, is added. 4. Process according to claim 1, characterized in that organic compounds containing at least one hydrophobic chain having at least 3 carbon atoms and having at least one hydrophilic group are added.