WO2024004703A1

WO2024004703A1 - Digestion accelerator and method for producing pulp using same

Info

Publication number: WO2024004703A1
Application number: PCT/JP2023/022358
Authority: WO
Inventors: 多加志田中; 豊敬播本
Original assignee: 日華化学株式会社
Priority date: 2022-06-30
Filing date: 2023-06-16
Publication date: 2024-01-04
Also published as: JP2024005966A

Abstract

This digestion accelerator comprises: a specific quaternary ammonium compound; and at least one amine compound selected from the group consisting of a specific primary monoamine, a specific secondary monoamine, and a specific tertiary monoamine. The mass ratio of the quaternary ammonium compound and the amine compound is 5:1 to 10,000:1. This method for producing pulp comprises a digestion step for adding a digestion accelerator and at least one main agent selected from the group consisting of an alkali-based main agent and a sulfite-based main agent, and thereby digesting a lignocellulose-containing material, wherein the digestion accelerator is the aforementioned digestion accelerator.

Description

Digestion accelerator and method for producing pulp using the same

The present invention relates to a digestion accelerator and a method for producing pulp using the same.

In the cooking step of the pulp production method, an alkaline base agent is used to pulp the material containing lignocellulose. In addition, a cooking accelerator is used to efficiently carry out cooking. As this digestion accelerator, Patent Document 1 discloses a digestion accelerator containing a quaternary ammonium compound. Patent Document 2 discloses a digestion accelerator containing at least one of glucose and fructose.

JP2019-65434A JP2020-2481A

When an alkaline base agent and the cooking accelerator disclosed in Patent Document 1 and Patent Document 2 are used in the cooking step of a pulp manufacturing method, lignocellulose is more efficiently produced than when cooking using only an alkaline base agent. can be used to cook materials containing However, from the viewpoint of the soaring price of wood due to the recent increase in demand for wood and the suppression of deforestation due to global warming, there is a need to further improve the efficiency of cooking in order to efficiently produce pulp.

In view of the above circumstances, the present invention provides a cooking accelerator that can efficiently cook a material containing lignocellulose in the cooking process of turning the material containing lignocellulose into pulp, and a method for producing pulp using the same. The purpose is to provide.

As a result of intensive studies in order to achieve the above object, the present inventors found that the compound is composed of a specific quaternary ammonium compound, a specific primary monoamine, a specific secondary monoamine, and a specific tertiary monoamine. a digestion accelerator containing at least one amine compound selected from the group, and a specific quaternary ammonium compound, and in the presence of this quaternary ammonium compound, sulfide ions, polysulfide ions, or The present inventors have discovered that a digestion accelerator containing a sulfur-containing compound that generates hydrogen ions can achieve the above object, and have completed the present invention.

In order to achieve the above object, [1] the digestion accelerator according to the present invention comprises a quaternary ammonium compound represented by the formula (1), a primary monoamine represented by the formula (2), a primary monoamine represented by the formula ( 3) and at least one amine compound selected from the group consisting of a secondary monoamine represented by formula (4) and a tertiary monoamine represented by formula (4).

In formula (1), R ¹ is an alkyl group having 8 to 22 carbon atoms, a hydroxyalkyl group having 8 to 22 carbon atoms, an alkenyl group having 8 to 22 carbon atoms, or a hydroxyalkenyl group having 8 to 22 carbon atoms. ,
R ² is an alkyl group having 1 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or (A ¹ O) _n Y is the basis,
R ³ and R ⁴ each independently represent an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, Aryl group, benzyl group which may have an alkyl group having 1 to 4 carbon atoms, phenethyl group which may have an alkyl group having 1 to 4 carbon atoms, glycidyl group, or (A ¹ O) _m Y is the basis,
N represents a nitrogen atom,
X ^p- represents a counter ion, is an inorganic anion or an organic anion, p represents the valence of the ion,
A ¹ O is an alkyleneoxy group having 2 to 4 carbon atoms, Y is a hydrogen atom or an acyl group,
n is an integer from 1 to 15, and m is an integer from 1 to 15.

In formula (2), R ⁵ is an alkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or ( A ² O) _k Z group, A ² O is an alkyleneoxy group having 2 to 4 carbon atoms, Z is a hydrogen atom or an acyl group, and k is an integer of 1 to 6.

In formula (3), R ⁶ and R ⁷ each independently represent an alkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, or a hydroxyalkyl group having 2 to 22 carbon atoms. 22 hydroxyalkenyl group or (A ³ O) _r Z group, A ³ O is an alkyleneoxy group having 2 to 4 carbon atoms, Z is a hydrogen atom or an acyl group, and r is 1 It is an integer between ~12.

In formula (4), R ⁸ and R ⁹ each independently represent an alkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, or a hydroxyalkyl group having 2 to 22 carbon atoms. 22 hydroxyalkenyl group or (A ⁴ O) _t Z group, A ⁴ O is an alkyleneoxy group having 2 to 4 carbon atoms, Z is a hydrogen atom or an acyl group, and t is 1 ~12 integers,
R ¹⁰ is an alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, or (A ⁵ O) _u Z A ⁵ O is an alkyleneoxy group having 2 to 4 carbon atoms, Z is a hydrogen atom or an acyl group, and u is an integer of 1 to 12.

[2] The mass ratio of the quaternary ammonium compound to the amine compound may be 5:1 to 10,000:1.

[3] The digestion accelerator according to the present invention includes a quaternary ammonium compound represented by formula (1) and a sulfide ion, a polysulfide ion, or and a sulfur-containing compound that generates hydrogen sulfide ions.

[4] The sulfur-containing compound may include thiosulfate, hydrogen thiosulfate, sulfite, hydrogen sulfite, disulfite, dithionite, dithionate, disulfate, peroxosulfate, peroxodisulfite, It may be composed of at least one compound selected from the group consisting of sulfates and polythionates.

[5] The mass ratio of the quaternary ammonium compound and the sulfur-containing compound may be 1:2 to 100:1.

In addition, in order to achieve the above object, [6] the method for producing pulp according to the present invention includes adding at least one base agent selected from the group consisting of an alkaline base agent and a sulfite base agent, and a digestion accelerator. , the cooking process includes a cooking step of cooking a material containing lignocellulose, and the cooking accelerator is the cooking accelerator according to [1] or [3].

[7] The content of the digestion accelerator may be 0.001% by mass to 1.0% by mass based on the material containing the lignocellulose.

According to the digestion accelerator of the present invention and the method for producing pulp using the same, materials containing lignocellulose can be efficiently digested.

Hereinafter, modes for carrying out the present invention (hereinafter simply referred to as "embodiments") will be described in detail. The following embodiments are examples for explaining the present invention, and are not intended to limit the present invention to the following contents. The present invention can be implemented with appropriate modifications within the scope of its gist.

[Embodiment 1]
The digestion accelerator of Embodiment 1 includes a quaternary ammonium compound and at least one amine compound selected from the group consisting of primary monoamines, secondary monoamines, and tertiary monoamines. First, quaternary ammonium compounds and amine compounds will be explained. Next, the digestion accelerator containing these will be explained.

(Quaternary ammonium compound)
The quaternary ammonium compound contained in the digestion accelerator of Embodiment 1 is a compound represented by the following formula (1).

N in formula (1) represents a nitrogen atom.

R ¹ in formula (1) is an alkyl group having 8 to 22 carbon atoms, a hydroxyalkyl group having 8 to 22 carbon atoms, an alkenyl group having 8 to 22 carbon atoms, or a hydroxyalkenyl group having 8 to 22 carbon atoms. .

R ² in formula (1) is an alkyl group having 1 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or ( A ¹ O) _n Y group. Here, A ¹ O is an alkyleneoxy group having 2 to 4 carbon atoms. n indicates the number of repeating units of the alkyleneoxy group, and is a number from 1 to 15. Y is a hydrogen atom or an acyl group. Moreover, "the number of repeating units of alkyleneoxy groups" means "the average number of moles of alkyleneoxy groups added." The same applies to all embodiments below.

R ³ and R ⁴ in formula (1) each independently represent an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, or an alkenyl group having 2 to 4 carbon atoms. 4 hydroxyalkenyl group, aryl group, benzyl group optionally having an alkyl group having 1 to 4 carbon atoms, phenethyl group optionally having an alkyl group having 1 to 4 carbon atoms, glycidyl group, or ( A ¹ O) _m Y group. Here, A ¹ O is an alkyleneoxy group having 2 to 4 carbon atoms. m represents the number of repeating units of the alkyleneoxy group, and is a number from 1 to 15. Y is a hydrogen atom or an acyl group. Furthermore, "a benzyl group which may have an alkyl group having 1 to 4 carbon atoms" refers to a benzyl group (C ₆ H ₅ CH ₂ -) and a group having 1 to 4 carbon atoms at CH ₂ in the benzyl group. Contains a benzyl group to which an alkyl group is attached. In addition, "a phenethyl group which may have an alkyl group having 1 to 4 carbon atoms" refers to a phenethyl group (C ₆ H ₅ CH ₂ CH ₂ -) and a phenethyl group in which CH ₂ has 1 to 4 carbon atoms. Contains a phenethyl group to which 4 alkyl groups are attached. C represents a carbon atom, and H represents a hydrogen atom. The same applies to all embodiments below.

It is preferable that R ¹ , R ² , R ³ , and R ⁴ in formula (1) have the following structure from the viewpoint of promoting cooking.
R ¹ is preferably an alkyl group having 10 to 18 carbon atoms, a hydroxyalkyl group having 10 to 18 carbon atoms, an alkenyl group having 10 to 18 carbon atoms, or a hydroxyalkenyl group having 10 to 18 carbon atoms. R ¹ is more preferably a linear alkyl group having 10 to 16 carbon atoms, a linear hydroxyalkyl group having 10 to 16 carbon atoms, a linear alkenyl group having 10 to 16 carbon atoms, or a carbon It is a linear hydroxyalkenyl group of 10 to 16 numbers.

R ² is preferably an alkyl group having 1 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or (A ¹ O ) _n Y group. Here, A ¹ O is an alkyleneoxy group having 2 to 4 carbon atoms. n indicates the number of repeating units of the alkyleneoxy group, and is a number from 1 to 6. Y is a hydrogen atom or an acyl group. R ² is more preferably a linear alkyl group having 1 to 22 carbon atoms, a linear hydroxyalkyl group having 1 to 22 carbon atoms, a linear alkenyl group having 2 to 22 carbon atoms, or a linear alkenyl group having 2 to 22 carbon atoms. 2 to 22 linear hydroxyalkenyl groups, or (A ¹ O) _n Y groups. Here, A ¹ O is an alkyleneoxy group having 2 to 4 carbon atoms. n indicates the number of repeating units of the alkyleneoxy group, and is a number from 1 to 4. Y is a hydrogen atom or an acyl group.

R ³ and R ⁴ are each independently preferably an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, or a hydroxy group having 2 to 4 carbon atoms. Alkenyl group, aryl group, benzyl group which may have an alkyl group having 1 to 4 carbon atoms, phenethyl group which may have an alkyl group having 1 to 4 carbon atoms, glycidyl group, or (A ¹ O ) _m Y group. Here, A ¹ O is an alkyleneoxy group having 2 to 4 carbon atoms. m represents the number of repeating units of the alkyleneoxy group, and is a number from 1 to 6. Y is a hydrogen atom or an acyl group. R ³ and R ⁴ each independently more preferably represent an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, or an alkenyl group having 2 to 4 carbon atoms. A hydroxyalkenyl group, an aryl group, a benzyl group which may have an alkyl group having 1 to 4 carbon atoms, a phenethyl group which may have an alkyl group having 1 to 4 carbon atoms, a glycidyl group, or (A ¹ O) _m Y group. Here, A ¹ O is an alkyleneoxy group having 2 to 4 carbon atoms. m indicates the number of repeating units of the alkyleneoxy group, and is a number from 1 to 4. Y is a hydrogen atom or an acyl group.

Furthermore, when R ² , R ³ , and R ⁴ in formula (1) are a hydroxyalkyl group, a hydroxyalkenyl group, or an alkyleneoxy group, they preferably have the following structure from the viewpoint of promoting digestion.
When R ² is a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or a (A ¹ O) _n Y group, the number of hydroxyalkyl groups and the number of hydroxyalkenyl groups , n is preferably an integer of 1 to 15. The total sum is more preferably 1 to 9, and even more preferably 1 to 6.

When R ³ or R ⁴ is each independently a hydroxyalkyl group having 1 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, or a (A ¹ O) _m Y group, the number of hydroxyalkyl groups The sum of m, the number of hydroxyalkenyl groups, and m is preferably an integer of 1 to 15. The total sum is more preferably 1 to 9, and even more preferably 1 to 6.

In R ² and R ³ or R ⁴ , R ² is a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or an (A ¹ O) _n Y group, and R ³ or When R ⁴ is each independently a hydroxyalkyl group having 1 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, or a (A ¹ O) _m Y group, the number of hydroxyalkyl groups and hydroxyalkenyl The total number of groups, n, and m is preferably an integer of 2 to 15. The total sum is more preferably 2 to 9, even more preferably 2 to 6.

In R ³ and R ⁴ , R ³ and R ⁴ are each independently a hydroxyalkyl group having 1 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, or an (A ¹ O) _m Y group; In some cases, the sum of the number of hydroxyalkyl groups, the number of hydroxyalkenyl groups, and m is preferably an integer of 2 to 15. The total sum is more preferably 2 to 9, even more preferably 2 to 6.

In R ² , R ³ , and R ⁴ , R ² is a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or a (A ¹ O) _n Y group, and R ³ , and R ⁴ are each independently a hydroxyalkyl group having 1 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, or a (A ¹ O) _m Y group, the number of hydroxyalkyl groups and hydroxy The total number of alkenyl groups, n, and m is preferably an integer of 3 to 15. The total sum is more preferably 3 to 9, and even more preferably 3 to 6.

X ^p- in formula (1) represents a counter ion. p indicates the valence of the ion. p is 1 to 40, preferably 1 to 20, more preferably 1 to 3 from the viewpoint of commercialization, industrialization, and cost. The counter ion is not limited as long as it is an anion that can form a salt with a quaternary ammonium compound. Examples of the counter ion include (i) an inorganic anion and (ii) an organic anion.

(i) Inorganic anions include halogen ions such as chloride ions and bromide ions, hydroxyl ions, sulfate ions, nitrate ions, phosphate ions, borate ions, sulfonate ions, hypochlorite ions, nitrite ions, Examples include phosphite ion, diphosphite ion, sulfite ion, hydrogen sulfite ion, sulfide ion, hydrogen sulfide ion, polysulfide ion, thiol ion, thiosulfate ion, thioglycolate and the like.

(ii) Examples of the organic anion include i) organic carboxylate ion, ii) phosphate ester ion, iii) sulfonate ion, iv) alkyl carbonate ion, v) sulfate ester ion, vi) anionic polymer, and the like. i) Examples of the organic carboxylate ion include formate ion, acetate ion, propionate ion, gluconate ion, lactate ion, fumarate ion, maleate ion, and adipate ion. ii) Examples of the phosphate ions include polyoxyalkylene alkyl ether phosphate ions, alkyl phosphate monoester ions, alkyl phosphate diester ions, alkenyl phosphate ions, and aryl phosphate ions. iii) Examples of the sulfonate ion include alkylbenzenesulfonate ion and alkylsulfonate ion. iv) Examples of the alkyl carbonate ion include methyl carbonate ion, ethyl carbonate ion, and the like. v) Examples of sulfate ions include alkyl sulfate ions, polyoxyalkylene alkyl ether sulfate ions, and the like. vi) Examples of anionic polymers include polyacrylic acid, polymaleic acid, polyphosphoric acid, and polysulfuric acid compounds.

Among the counter ions, from the viewpoint of promoting digestion, (i) inorganic anions are preferably halogen ions such as chloride ions and bromide ions, sulfate ions, nitrate ions, borate ions, and phosphate ions. (ii) Organic anions include alkyl phosphate monoester ions whose alkyl groups have 1 to 4 carbon atoms, such as butyl phosphate ions; alkyl phosphate diesters whose alkyl groups have 1 to 4 carbon atoms, such as dibutyl phosphate ions; Ion; Alkylbenzenesulfonic acid ion having 1 to 4 carbon atoms such as p-toluenesulfonic acid; carbon of an alkyl group such as methyl sulfate ion (CH ₃ SO ₄ ⁻ ) and ethyl sulfate ion (C ₂ H ₅ SO ₄ ⁻ ) Alkyl sulfate ions having a number of 1 to 4 are preferred.

(amine compound)
The amine compound contained in the digestion accelerator of Embodiment 1 is composed of at least one amine compound selected from the group consisting of primary monoamines, secondary monoamines, and tertiary monoamines.

(Primary monoamine)
The primary monoamine is a compound represented by the following formula (2).

In formula (2), R ⁵ is an alkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or ( A ² O) _k Z group. Here, A ² O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. k is an integer from 1 to 6.

From the viewpoint of promoting cooking, R ⁵ is preferably an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, a hydroxyalkyl group having 1 to 18 carbon atoms, or a hydroxyalkenyl group having 2 to 18 carbon atoms. or (A ² O) _k Z group. Here, A ² O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. k is an integer from 1 to 2. R ⁵ is more preferably an alkyl group having 10 to 14 carbon atoms, an alkenyl group having 10 to 14 carbon atoms, a hydroxyalkyl group having 10 to 14 carbon atoms, a hydroxyalkenyl group having 10 to 14 carbon atoms, or (A ² O) _k Z group. Here, A ² O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. k is 1.

(Secondary monoamine)
The secondary monoamine is a compound represented by the following formula (3).

In formula (3), R ⁶ is an alkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or ( A ³ O) _r1 Z group. Here, A ³ O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. r1 is an integer from 1 to 12.
In formula (3), R ⁷ is an alkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or ( A ³ O) _r2 Z group. Here, A ³ O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. r2 is an integer from 1 to 12. Further, R ⁶ and R ⁷ may be the same or different.
Here, the (A ³ O) _r1 Z group of R ⁶ and the (A ³ O) _r2 Z group of R ⁷ may be collectively referred to as an (A ³ O) _r Z group.

R ⁶ and R ⁷ in formula (3) preferably have the following structure from the viewpoint of promoting digestion.
R ⁶ is preferably an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, a hydroxyalkyl group having 1 to 18 carbon atoms, a hydroxyalkenyl group having 2 to 18 carbon atoms, or (A ³ O ) _r1 is a Z group. Here, A ³ O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. r1 is an integer from 1 to 6. R ⁶ is more preferably an alkyl group having 10 to 14 carbon atoms, an alkenyl group having 10 to 14 carbon atoms, a hydroxyalkyl group having 10 to 14 carbon atoms, a hydroxyalkenyl group having 10 to 14 carbon atoms, or (A ³ O) _r1 is a Z group. Here, A ³ O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. r1 is an integer from 2 to 4.

R ⁷ is preferably an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, a hydroxyalkyl group having 1 to 18 carbon atoms, a hydroxyalkenyl group having 2 to 18 carbon atoms, or (A ³ O ) _r2 Z group. Here, A ³ O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. r2 is an integer from 1 to 6. R ⁷ is more preferably an alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, or (A ³ O) _r2 is a Z group. Here, A ³ O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. r2 is an integer from 2 to 4.

Furthermore, when R ⁶ and R ⁷ in formula (3) are a hydroxyalkyl group, a hydroxyalkenyl group, or an alkyleneoxy group, from the viewpoint of promoting cooking, R ⁶ and R ⁷ have the following structure. It is preferable.
When R ⁶ is a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or an (A ³ O) _r1 Y group, the number of hydroxyalkyl groups and the number of hydroxyalkenyl groups , r1 is an integer from 1 to 12. The total sum is preferably 1 to 6, more preferably 1 to 4.

When R ⁷ is a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or an (A ³ O) _r2 Y group, the number of hydroxyalkyl groups and the number of hydroxyalkenyl groups , r2 is an integer from 1 to 12. The total sum is preferably 1 to 6, more preferably 1 to 4.

In R ⁶ and R ⁷ , R ⁶ is a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or an (A ³ O) _r1 Y group, and R ⁷ is When it is a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or an (A ³ O) _r2 Y group, preferably the number of hydroxyalkyl groups, the number of hydroxyalkenyl groups, and r1 are , r2 is an integer from 2 to 12. The total sum is preferably 2 to 6, more preferably 2 to 4. Further, R ⁶ and R ⁷ may have the same structure or different structures.

(tertiary monoamine)
The tertiary monoamine is a compound represented by the following formula (4).

In formula (4), R ⁸ is an alkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or ( A ⁴ O) _t1 Z group. A ⁴ O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. t1 is an integer from 1 to 12.
In formula (4), R ⁹ is an alkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or ( A ⁴ O) _t2 Z group. A ⁴ O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. t2 is an integer from 1 to 12. Further, R ⁸ and R ⁹ may have the same structure or different structures.
Here, the (A ⁴ O) _t1 Z group of R ⁸ and the (A ⁴ O) _t2 Z group of R ⁹ may be collectively referred to as an (A ⁴ O) _t Z group.
In formula (4), R ¹⁰ is an alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, or ( A ⁵ O) _u Z group. A ⁵ O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. u is an integer from 1 to 12.

R ⁸ , R ⁹ and R ¹⁰ in formula (4) preferably have the following structure from the viewpoint of promoting cooking.
R ⁸ is preferably an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, a hydroxyalkyl group having 1 to 18 carbon atoms, a hydroxyalkenyl group having 2 to 18 carbon atoms, or (A ⁴ O ) _t1 is a Z group. A ⁴ O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. t1 is an integer from 1 to 6. R ⁸ is more preferably an alkyl group having 10 to 14 carbon atoms, an alkenyl group having 10 to 14 carbon atoms, a hydroxyalkyl group having 10 to 14 carbon atoms, a hydroxyalkenyl group having 10 to 14 carbon atoms, or (A ⁴ O) _t1 Z group. A ⁴ O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. t1 is an integer from 1 to 4.

R ⁹ is preferably an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, a hydroxyalkyl group having 1 to 18 carbon atoms, a hydroxyalkenyl group having 2 to 18 carbon atoms, or (A ⁴ O ) _t2 Z group. A ⁴ O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. t2 is an integer from 1 to 6. R ⁹ is more preferably an alkyl group having 10 to 14 carbon atoms, an alkenyl group having 10 to 14 carbon atoms, a hydroxyalkyl group having 10 to 14 carbon atoms, a hydroxyalkenyl group having 10 to 14 carbon atoms, or (A ⁴ O) _t2 Z group. A ⁴ O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. t2 is an integer from 1 to 4.

R ¹⁰ is preferably an alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, or (A ⁵ O ) _u Z group. A ⁵ O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. u is an integer from 1 to 6. R ¹⁰ is more preferably an alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, or (A ⁵ O) _u Z group. A ⁵ O is an alkyleneoxy group having 2 to 4 carbon atoms, and Z is a hydrogen atom or an acyl group. u is an integer from 1 to 4.

Furthermore, when R ⁸ , R ⁹ , and R ¹⁰ in formula (4) are a hydroxyalkyl group, a hydroxyalkenyl group, or an alkyleneoxy group, they preferably have the following structure from the viewpoint of promoting digestion.
When R ⁸ is a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or a (A ⁴ O) _t1 Z group, the number of hydroxyalkyl groups and the number of hydroxyalkenyl groups , t1 is an integer from 1 to 12. The total sum is preferably 1 to 6, more preferably 1 to 4.

When R ⁹ is a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or a (A ⁴ O) _t2 Z group, the number of hydroxyalkyl groups and the number of hydroxyalkenyl groups , t2 is an integer from 1 to 12. The total sum is preferably 1 to 6, more preferably 1 to 4.

When R ¹⁰ is a hydroxyalkyl group having 1 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, or a (A ⁵ O) _u Z group, the number of hydroxyalkyl groups and the number of hydroxyalkenyl groups , u is an integer from 1 to 12. The total sum is preferably 1 to 6, more preferably 1 to 4.

In R ⁸ and R ⁹ , R ⁸ is a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or a (A ⁴ O) _t1 Z group, and R ⁹ is a In the case of a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or a (A ⁴ O) _t2 Z group, the number of hydroxyalkyl groups, the number of hydroxyalkenyl groups, t1, t2, and The sum total is an integer from 2 to 12. The total sum is preferably 2 to 6, more preferably 2 to 4. Further, R ⁸ and R ⁹ may have the same structure or different structures.

In R ⁸ and R ¹⁰ , R ⁸ is a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or a (A ⁴ O) _t1 Z group, and R ¹⁰ is In the case of a hydroxyalkyl group having 1 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, or a (A ⁵ O) _u Z group, the number of hydroxyalkyl groups, the number of hydroxyalkenyl groups, t1, u, and The sum total is an integer from 2 to 12. The total sum is preferably 2 to 6, more preferably 2 to 4. Further, R ⁸ and R ¹⁰ may have the same structure or different structures.

In R ⁹ and R ¹⁰ , R ⁹ is a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or a (A ⁴ O) _t2 Z group, and R ¹⁰ is In the case of a hydroxyalkyl group having 1 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, or a (A ⁵ O) _u Z group, the number of hydroxyalkyl groups, the number of hydroxyalkenyl groups, t2, u, and The sum total is an integer from 2 to 12. The total sum is preferably 2 to 6, more preferably 2 to 4. Further, R ⁹ and R ¹⁰ may have the same structure or different structures.

In R ⁸ , R ⁹ , and R ¹⁰ , R ⁸ is a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or a (A ⁴ O) _t1 Z group, and R ⁹ is , a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or a (A ⁴ O) _t2 Z group, and R ¹⁰ is a hydroxyalkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 2 to 4 carbon atoms, ~4 hydroxyalkenyl group or (A ⁵ O) _u Z group, the sum of the number of hydroxyalkyl groups, the number of hydroxyalkenyl groups, t1, t2, and u is an integer of 3 to 12. It is. The total sum is preferably 3 to 6, more preferably 3 to 4. Furthermore, R ⁸ , R ⁹ , and R ¹⁰ may be the same or different.

The above-mentioned amine compound is preferably a secondary monoamine from the viewpoint of promoting cooking, more preferably a primary monoamine, and even more preferably a tertiary monoamine.

(Digestion accelerator)
The digestion accelerator of Embodiment 1 contains the above-mentioned quaternary ammonium compound and amine compound. The mass ratio of the quaternary ammonium compound to the amine compound is 5:1 to 10,000:1. This mass ratio is preferably 10:1 to 10,000:1, more preferably 10:1 to 1,000:1 from the viewpoint of promoting cooking.

The content of the digestion accelerator in Embodiment 1 is 0.001% by mass to 1.0% by mass based on the material containing lignocellulose. For example, the content of the digestion accelerator in Embodiment 1 is 1.0 to 1000 mg, preferably 2 to 500 mg, and more preferably 2 to 500 mg from the viewpoint of promoting digestion, per 100 g of the material containing lignocellulose. is 5 to 200 mg.

The digestion accelerator of Embodiment 1 may contain two or more types of quaternary ammonium compounds having different structures. Moreover, the digestion accelerator of Embodiment 1 may contain two or more types of amine compounds.

By using the digestion accelerator of Embodiment 1, which contains the specific quaternary ammonium compound and the specific amine compound described above, in the cooking process, the activity of the quaternary ammonium compound is not lost, and the ligno Materials containing cellulose can be efficiently digested.

[Embodiment 2]
Next, the digestion accelerator of Embodiment 2 will be explained.
The digestion accelerator of Embodiment 2 comprises a quaternary ammonium compound and a sulfur-containing compound that generates sulfide ions, polysulfide ions, or hydrogen sulfide ions in the presence of the quaternary ammonium compound. include. First, quaternary ammonium compounds and sulfur-containing compounds will be explained. Next, the digestion accelerator containing these will be explained.

(Quaternary ammonium compound)
The quaternary ammonium compound contained in the digestion accelerator of Embodiment 2 is substantially the same as the quaternary ammonium compound described in Embodiment 1.

(Sulfur-containing compounds)
The sulfur-containing compound contained in the digestion accelerator of Embodiment 2 is a compound that generates sulfide ions, polysulfide ions, or hydrogen sulfide ions in the presence of a quaternary ammonium compound. The sulfur-containing compound may be, for example, thiosulfate, hydrogen thiosulfate, sulfite, bisulfite, disulfite, dithionite, dithionate, disulfate, peroxosulfate, peroxodisulfate, and at least one compound selected from the group consisting of polythionates. The sulfur-containing compound is preferably composed of at least one compound selected from the group consisting of sodium thiosulfate, ammonium thiosulfate, sodium hydrogen sulfide, and sodium sulfide from the viewpoint of promoting digestion.

(Digestion accelerator)
The digestion accelerator of Embodiment 2 contains the above-mentioned quaternary ammonium compound and sulfur-containing compound. The mass ratio of the quaternary ammonium compound and the sulfur-containing compound is 1:1 to 100:1. This mass ratio is preferably 1:1 to 50:1, more preferably 1:1 to 20:1, from the viewpoint of promoting cooking.

The content of the digestion accelerator in Embodiment 2 is 0.001% by mass to 1.0% by mass based on the material containing lignocellulose. For example, the content of the digestion accelerator in Embodiment 2 is 1.0 to 1000 mg, preferably 2 to 500 mg, and more preferably 2 to 500 mg from the viewpoint of promoting digestion, per 100 g of the material containing lignocellulose. is 5 to 200 mg.

The digestion accelerator of Embodiment 2 may contain two or more types of quaternary ammonium compounds having different structures. Moreover, the digestion accelerator of Embodiment 1 may contain two or more types of sulfur-containing compounds.

By using the digestion accelerator of Embodiment 2 containing the specific quaternary ammonium compound and the specific sulfur-containing compound described above in the cooking process, the material containing lignocellulose can be efficiently cooked. That is, by containing a sulfur-containing compound in the digestion accelerator, a state is created in which many sulfide ions, polysulfide ions, hydrogen sulfide ions, etc. are present around the quaternary ammonium compound. When this digestion accelerator is used in the cooking process, lignocellulose can be cooked in an irreversible reaction. Note that, for example, in the cooking process using the alkaline cooking method, sodium sulfide or the like is used separately from the cooking accelerator. Since the sulfide ions, polysulfide ions, hydrogen sulfide ions, etc. generated at this time are not present in large numbers around the quaternary ammonium compound, irreversible reactions are difficult to occur. For this reason, it is difficult to efficiently digest lignocellulose.

[Solvents and additives that can be added to Embodiment 1 and Embodiment 2]
The digestion accelerator of Embodiment 1 and Embodiment 2 described above may contain water or an organic solvent. The digestion accelerator can be used, for example, by dissolving or emulsifying it in water or an organic solvent. Examples of organic solvents include lower alcohols having 1 to 6 carbon chains such as methanol, ethanol, and propanol; alkylene glycols having 1 to 6 carbon chains such as ethylene glycol, diethylene glycol, and propylene glycol; 3-methyl -3-methoxybutanol and the like.

The digestion accelerator of Embodiment 1 and Embodiment 2 described above may further contain an additive from the viewpoint of efficiently permeating the digestion accelerator into the material containing lignocellulose.

(Additive)
Examples of additives include nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, natural oils such as mineral oil and orange oil, alkaline agents, acids, and the like. Moreover, from the viewpoint of improving the detergency of the pulp, the digestion accelerator may further contain, for example, an antifoaming agent, a detergent, and the like. These additives can be added to the digestion accelerator insofar as they do not impair the effects of the digestion accelerator.

The above-mentioned alkali agents include inorganic alkalis. Examples of the inorganic alkali include sodium hydroxide, potassium hydroxide, sodium carbonate, and ammonia.

Examples of the above-mentioned acids include inorganic acids such as hydrochloric acid, nitric acid, and phosphoric acid, and organic acids such as acetic acid, formic acid, lactic acid, and oxalic acid.

The above is a description of the compounds contained in the digestion accelerators of Embodiment 1 and Embodiment 2. Next, a method for producing the quaternary ammonium compound contained in the digestion accelerator of Embodiment 1 and Embodiment 2, and a method for producing the amine compound of Embodiment 1 will be explained.

(Method for producing quaternary ammonium compound)
Quaternary ammonium compounds can be synthesized by various methods. As an example of a synthesis method, for example, a quaternizing agent having R ⁴ is added to a tertiary amine having R ¹ , R ² , and R ³ and the mixture is reacted at a temperature of 70 to 150°C. A quaternary ammonium compound is obtained.

In addition, as an example of another synthesis method, in the case of a quaternary ammonium compound in which R ⁴ is an (AO)H group, a tertiary amine having R ¹ , R ² , and R ³ is neutralized with any acid. After that, an amount of alkylene oxide equivalent to the amount of tertiary amine is added to the neutralized mixture, and a quaternization reaction is carried out at a temperature of 70 to 120° C. to obtain a quaternary ammonium compound. Here, AO is an alkyleneoxy group.

In addition, as an example of another synthesis method, a fourth compound in which R ² , R ³ , and R ⁴ are substituents represented by (AO) _n H group, (AO) _m1 H group, and (AO) _m2 H group In the case of a class ammonium compound, a predetermined amount of alkylene oxide is added to trialkanolamine, and the above substituent is added at a temperature of 100 to 150°C. Next, a quaternizing agent having R ¹ is added to the mixture and reacted at a temperature of 60 to 130° C. to obtain a quaternary ammonium compound. n, m1 and m2 are, for example, integers from 1 to 9.

The amine compound contained in the digestion accelerator of Embodiment 1 and the sulfur-containing compound contained in the digestion accelerator of Embodiment 2 can be synthesized by a known method. For example, a tertiary monoamine can be obtained by subjecting an alkylamine having 1 to 22 carbon atoms to a polymerization reaction with an alkylene oxide at a temperature of 70 to 150°C.

(Pulp manufacturing method)
The digestion accelerators of Embodiment 1 and Embodiment 2 described above are used in the digestion step of the pulp manufacturing method. Next, a method for producing pulp using these digestion accelerators will be explained.
The method for producing pulp includes a cooking process of cooking a material containing lignocellulose using at least one base agent selected from the group consisting of an alkaline base agent and a sulfite base agent and a digestion accelerator, and a pulp obtained by cooking. The process includes a washing process to wash the pulp, a screen process to remove dust from the pulp, and a bleaching process to bleach the pulp.

In the cooking step, for example, the cooking accelerator of the embodiment, a material containing lignocellulose, and an alkaline base agent are added to a cooking pot, and the mixture is cooked under high temperature and high pressure conditions. Through this cooking, fibers (pulp) are extracted from lignocellulose.

The temperature, pressure, and time in the cooking step are appropriately set depending on the type, shape, and size of the material containing lignocellulose. For example, when the material containing lignocellulose is wood chips, the temperature is, for example, 50 to 300°C, and preferably 80 to 250°C from the viewpoint of reducing the load on equipment such as a digester. The pressure is, for example, normal pressure to 10 MPa, and preferably normal pressure to 5 MPa from the viewpoint of reducing the load on equipment such as a digester. The time is, for example, 1 to 5 hours from the viewpoint of reducing the load on equipment such as the digester.

Examples of the cooking method employed in this cooking step include an alkaline cooking method, a sulfite cooking method, and the like. The alkaline cooking method can be further divided into Kraft method, soda method, soda carbonate method, polysulfide method, etc. The sulfite cooking method can be further divided into an alkaline sulfite method, a neutral sulfite method, a bisulfite method, and the like. The cooking method is preferably an alkaline cooking method from the viewpoint of promoting cooking. Among the alkaline cooking methods, the Kraft method and the polysulfide method are preferred from the viewpoint of promoting cooking.

Examples of the alkaline base agent used in the alkaline cooking method include sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, and the like. The amount of the alkaline base agent used in the cooking step varies depending on the type of material containing lignocellulose, but is 1 to 120 parts by mass based on 100 parts by mass of the material containing lignocellulose. From the viewpoint of efficient cooking and exerting the effect of the digestion accelerator, the amount is preferably 3 to 60 parts by mass, more preferably 5 to 60 parts by mass.

The Kraft method, which is one of the alkaline cooking methods, is a cooking method that uses an alkaline base ingredient and sodium sulfide. For example, when the alkaline main ingredient is sodium hydroxide, the amount of sodium sulfide used is 1 to 200 parts by mass based on 100 parts by mass of sodium hydroxide, and from the viewpoint of efficient cooking, it is preferable. The amount is 10 to 100 parts by mass.

The polysulfide method, which is one of the alkaline cooking methods, is a cooking method using an alkaline main ingredient, sodium sulfide, and sodium polysulfide (Na ₂ Sx, x=2 to 5). For example, when the alkaline main ingredient is sodium hydroxide, the amount of sodium sulfide used is 1 to 200 parts by mass based on 100 parts by mass of sodium hydroxide, and from the viewpoint of efficient cooking, it is preferable. The amount is 10 to 100 parts by mass. The amount of sodium polysulfide used is 1 to 200 parts by mass, preferably 10 to 100 parts by mass from the viewpoint of efficient cooking, per 100 parts by mass of sodium hydroxide.

The soda method, which is one of the alkaline cooking methods, is a method of cooking using an alkaline base ingredient. For example, sodium hydroxide is used as the alkaline base agent.

Examples of materials containing lignocellulose include wood, plants, and the like. Examples of the wood include L wood made from hardwood, N wood made from coniferous wood, and the like. In addition, examples of plants include bakasu, reed, kenaf, mulberry, bamboo, and the like. Wood and plants are used, for example, in the form of chips.

The present invention will be explained in more detail with reference to the following Examples and Comparative Examples, but the present invention is not limited to the following Examples. In Examples and Comparative Examples, the following materials containing a quaternary ammonium compound, an amine compound, a sulfur-containing compound, and a lignocellulose were used.

(Quaternary ammonium compound)
R ¹ , R ² , R ³ , R ⁴ _, and counter ions of the quaternary ammonium compounds (E1 to E8, e9 to e10) used in Examples and Comparative Examples have the structures shown in Table 1. Quaternary ammonium compounds (E1 to E8, e9 to e10) were each synthesized.

(Synthesis of quaternary ammonium compound E1)
One molar equivalent of lauryldimethylamine was added to a four-necked flask equipped with a reflux condenser and heated to 85-95°C. To this, 1.1 molar equivalent of diethyl sulfuric acid was added dropwise while stirring to cause a quaternization reaction, thereby obtaining a quaternary ammonium compound E1.

(Synthesis of quaternary ammonium compound E2)
One molar equivalent of lauryl dimethylamine and twice the amount of distilled water relative to the mass of lauryl dimethylamine were added to a four-necked flask equipped with a reflux condenser, and the mixture was heated to 85 to 95°C. To this, 1.1 molar equivalent of benzyl chloride was added dropwise while stirring to cause a quaternization reaction, thereby obtaining E2.

(Synthesis of quaternary ammonium compound E3)
One molar equivalent of laurylamine was added to a pressure-resistant reaction vessel, the atmosphere was purged with nitrogen, and the vessel was heated to 120 to 130°C. Two molar equivalents of ethylene oxide were blown into this to obtain an adduct in which 2 molar equivalents of ethylene oxide was added to laurylamine. Next, 1 molar equivalent of the obtained adduct was added to a four-neck flask equipped with a reflux condenser and heated to 85 to 95°C. 1.1 molar equivalent of diethyl sulfuric acid was added dropwise to the mixture while stirring to cause a quaternization reaction, thereby obtaining a quaternary ammonium compound E3.

(Synthesis of quaternary ammonium compound E4)
One molar equivalent of laurylamine was added to a pressure-resistant reaction vessel, the atmosphere was purged with nitrogen, and the vessel was heated to 120 to 130°C. Two molar equivalents of ethylene oxide were blown into this to obtain an adduct in which 2 molar equivalents of ethylene oxide was added to laurylamine. Next, twice the amount of distilled water based on the mass of the obtained adduct was added to a pressure-resistant reaction vessel, and 1 molar equivalent of nitric acid was added to neutralize the mixture. Thereafter, the pressure-resistant reaction vessel was heated to 85 to 95°C, and 1.1 molar equivalent of ethylene oxide was blown into it to cause a quaternization reaction. Finally, dehydration was performed under reduced pressure in an evaporator at 70°C to obtain quaternary ammonium compound E4.

(Synthesis of quaternary ammonium compound E5)
One molar equivalent of stearyldimethylamine was added to a four-neck flask equipped with a reflux condenser and heated to 85-95°C. Thereto, 1.1 molar equivalent of dimethyl sulfuric acid was added dropwise while stirring to cause a quaternization reaction, thereby obtaining quaternary ammonium compound E5.

(Synthesis of quaternary ammonium compound E6)
Into a pressure-resistant reaction vessel, 1 molar equivalent of octyldimethylamine was added, followed by 2 times the amount of distilled water based on the mass of octylamine, and 0.7 molar equivalent of phosphoric acid. Thereafter, the pressure-resistant reaction vessel was heated to 85 to 95° C., and 1.1 molar equivalent of ethylene oxide was blown into it to cause a quaternization reaction, thereby obtaining quaternary ammonium compound E6.

(Synthesis of quaternary ammonium compound E7)
One molar equivalent of laurylamine was added to a pressure-resistant reaction vessel, the atmosphere was purged with nitrogen, and the vessel was heated to 120 to 130°C. 8 molar equivalents of ethylene oxide was blown into this to obtain an adduct in which 8 molar equivalents of ethylene oxide was added to laurylamine. Next, twice the amount of distilled water based on the mass of the obtained adduct was added to a pressure-resistant reaction vessel, and 1.0 molar equivalent of para-toluenesulfonic acid was added to neutralize the mixture. Thereafter, the pressure-resistant reaction vessel was heated to 85 to 95° C., and 1.1 molar equivalent of ethylene oxide was blown into it to cause a quaternization reaction, thereby obtaining quaternary ammonium compound E7.

(Quaternary ammonium compound E8)
Didecyldimethylammonium chloride (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was used.

(Synthesis of quaternary ammonium compound e9)
One molar equivalent of laurylamine was added to a pressure-resistant reaction vessel, the atmosphere was purged with nitrogen, and the vessel was heated to 120 to 130°C. 32 molar equivalents of ethylene oxide was blown into this to obtain an adduct in which 32 molar equivalents of ethylene oxide was added to laurylamine. One molar equivalent of the obtained adduct was added to a four-necked flask equipped with a reflux condenser and heated to 85 to 95°C. Thereto, 1.1 molar equivalent of dimethyl sulfuric acid was added dropwise while stirring to cause a quaternization reaction, thereby obtaining quaternary ammonium compound E9.

(Synthesis of quaternary ammonium compound e10)
1 molar equivalent of hexylamine was added to a pressure-resistant reaction vessel, the atmosphere was purged with nitrogen, and the vessel was heated to 120 to 130°C. Two molar equivalents of ethylene oxide were blown into this to obtain an adduct in which 2 molar equivalents of ethylene oxide was added to laurylamine. Next, 1 molar equivalent of the obtained adduct was added to a four-neck flask equipped with a reflux condenser and heated to 85 to 95°C. Thereto, 1.1 molar equivalent of diethyl sulfuric acid was added dropwise while stirring to cause a quaternization reaction, thereby obtaining a quaternary ammonium compound E10.

(amine compound)
The following amine compounds were used as the amine compounds.
A1 tetradecylamine was used as the primary monoamine.
A2 diethanolamine was used as the secondary monoamine.
As tertiary monoamines, A3 N,N-dimethyldecylamine, A4 N-lauryldiethanolamine, and A5 triethanolamine were used.
These amine compounds were those manufactured by Tokyo Kasei Kogyo Co., Ltd.

Tertiary monoamines a6 and a7 were synthesized as follows.

(Synthesis of tertiary monoamine a6)
One molar equivalent of laurylamine was added to a pressure-resistant reaction vessel, the atmosphere was purged with nitrogen, and the vessel was heated to 120 to 130°C. 30 molar equivalents of ethylene oxide was blown into this to obtain an adduct a6 in which 30 molar equivalents of ethylene oxide was added to laurylamine.

(Synthesis of tertiary monoamine a7)
One molar equivalent of laurylamine was added to a pressure-resistant reaction vessel, the atmosphere was purged with nitrogen, and the vessel was heated to 120 to 130°C. 50 molar equivalents of ethylene oxide was blown into this to obtain an adduct a7 in which 50 molar equivalents of ethylene oxide was added to laurylamine.

(Sulfur-containing compounds)
The sulfur-containing compounds used were B1 sodium thiosulfate, B2 ammonium thiosulfate, B3 sodium hydrogen sulfide, B4 sodium sulfide, B5 sodium tetrasulfide, B6 potassium sulfite, B7 sodium bisulfite, and b8 sodium sulfate.
The sulfur-containing compounds B1 to B4, B6 to B7, and b8 were manufactured by Fuji Film Wako Pure Chemical Industries, Ltd. The sulfur-containing compound B5 was manufactured by Nagao Corporation.

(Materials containing lignocellulose)
Wood chips were used as the material containing lignocellulose.
L wood Wood chips made from hardwood (acacia: eucalyptus = 7:3),
N material Wood chips made from coniferous trees (Japanese red pine).

Various evaluations were performed using the materials containing the above-mentioned quaternary ammonium compounds, amine compounds, sulfur-containing compounds, and lignocellulose.

(Example 1, L material, Kraft method, cooking accelerator containing amine compound)
Cooking was performed by the Kraft method using L wood as wood chips and a cooking accelerator containing a quaternary ammonium compound and an amine compound. First, the L material was passed through a stainless steel sieve with an opening of 710 μm, and the L material remaining on the sieve was dried at 60° C. for 24 hours. The content of quaternary ammonium compound E4 (pure part) and amine compound A1 (pure part) is 0.03% by mass with respect to L material (wood chips), and the content of quaternary ammonium compound E4 (pure part) and amine compound The digestion accelerator was prepared so that the mass ratio with A1 (pure content) was 100:1. Specifically, for 50.0 g of L material (wood chips), 14.85 mg of quaternary ammonium compound E4 (purity) and 0.15 mg of amine compound A1 (purity) were placed in a container, and distilled water was added. The digestion accelerator used in Example 1 was obtained.
Next, add 6.9 g of sodium sulfide pentahydrate (3.2 g as pure sodium sulfide) and 11.2 g of sodium hydroxide to a beaker, and add distilled water so that the total mass is 145 g. An alkaline aqueous solution was obtained. The previously prepared cooking accelerator was added to this aqueous solution, and distilled water was added so that the total mass was 150 g, followed by stirring to obtain a cooking liquid.
50.0 g of the prepared L material and 150 g of the cooking liquid were placed in a pot (MINI COLOR, manufactured by Texam Giken Co., Ltd.) and cooked at 150° C. for 50 minutes.

After cooking, Example 1 was evaluated for wood piece residual rate, yield rate, and kappa number, and the results are shown in Table 2. In addition, the wood piece residual rate, yield rate, and kappa number were each evaluated using the following procedures.

<Wood piece residual rate (wood chip residual rate)>
By examining the wood chip residual rate (wood chip residual rate), it is possible to judge how far the cooking of the wood chips (wood chips) has progressed. The wood chip residual rate is also called the wood chip residual rate.

The wood piece residual rate was calculated from the following formula.
Wood piece residual rate (%) = (mass of residue after cooking (g) / mass of sample before cooking (g)) x 100
Here, the following treatment was performed and the residue after cooking was used. First, the mixture obtained by cooking was sieved. Next, the residue remaining on a stainless steel sieve with an opening of 710 μm was washed with water, and washing was repeated until the washed water became colorless. Thereafter, this residue was dried at 105° C. for 10 hours to obtain a residue. Pre-cooked samples are wood chips that are sieved and dried before being cooked. For example, the pre-cooked sample of Example 1 is L material that was sieved and dried before being cooked.

The evaluation criteria for the residual rate of wood pieces when using the Kraft method and L material were as follows.
Excellent: Less than 0.5% wood fragment residual rate,
Good: The residual rate of wood pieces is 0.5% or more and less than 1.5%,
Poor: The residual rate of wood pieces is 1.5% or more and less than 2.5%,
Bad: Wood piece residual rate is 2.5% or more.

<Yield rate>
The yield rate is the yield rate of the pulp obtained after cooking, and was determined from the following formula.
Yield rate (%) = (((i) Mass of recovered pulp (g) + (ii) Mass of remaining wood pieces (g) x 1/2) / (iii) Mass of sample before cooking (g)) ×100
(i) The recovered pulp mass was the mass of the pulp obtained after the following treatment. First, the mixture obtained by cooking was passed through a stainless steel sieve with an opening of 710 μm, and the mixture that passed through the sieve was further passed through a stainless steel sieve with a finer opening of 75 μm. The residue remaining on the sieve was washed with water, and washing was repeated until the washed water became colorless. This residue was then dried at 105°C for 10 hours. Thereafter, the mass of the residue after drying was measured, and this was taken as the recovered pulp mass.
(ii) The mass of the remaining wood pieces was defined as the mass of the residue obtained after the following treatment. First, the mixture obtained by cooking was passed through a stainless steel sieve with an opening of 710 μm, and the remaining residue was washed with water, and the washing was repeated until the washed water became colorless. This residue was then dried at 105°C for 10 hours. Thereafter, the mass of the residue after drying was measured, and this was taken as the mass of the remaining wood piece. Here, assuming that the residue after cooking is to be digested again, the mass of the residue obtained after the treatment (the mass of the remaining wood pieces) multiplied by 1/2 is the mass of pulp that is expected to be further recovered. This is added to the molecule in the formula.
(iii) Pre-cooked samples are wood chips that are sieved and dried before being cooked. For example, the pre-cooked sample of Example 1 is L material that was sieved and dried before being cooked.

The evaluation criteria for yield rate when using the Kraft method and L material were as follows.
Excellent: Yield rate is 52.5% or more,
Good: Yield rate is less than 52.5%, 52.0% or more,
Poor: Yield rate is less than 52.0%, 51.5% or more,
Bad: Yield rate is less than 51.5%.

<Kappa number>
The kappa number indicates the content of residual lignin. The Kappa number of the pulp obtained after cooking is low due to the low content of residual lignin. Furthermore, by examining the kappa number of the pulp obtained after cooking, it is possible to determine how far the cooking of the wood chips has progressed.
The pulp obtained after cooking was subjected to the following treatment. First, the mixture obtained by cooking was passed through a stainless steel sieve with an opening of 710 μm, and the mixture that passed through the sieve was further passed through a stainless steel sieve with a finer opening of 75 μm. The residue remaining on the sieve was washed with water, and washing was repeated until the washed water became colorless. This residue was then dried at 105°C for 10 hours. This was made into pulp. The kappa number was determined by the method described in JIS P 8211 (2011).

The evaluation criteria for kappa number when using the Kraft method and L material were as follows.
Excellent: Kappa number is less than 15.5,
Good: Kappa number is 15.5 or more and less than 16.0,
Poor: Kappa number is 16.0 or more and less than 16.5,
Bad: Kappa number is 16.5 or more.

(Examples 2 to 17, Comparative Examples 1 to 17, L material, Kraft method, cooking accelerator containing amine compound)
Examples 2 to 17 and Comparative Examples 1 to 17 are the same as Example 1 except that the types, usage amounts, and mass ratios of the quaternary ammonium compound and amine compound were changed, as shown in Tables 2 and 3. Cooking was performed and evaluated using the same method as above. In addition, in Comparative Example 1, cooking was performed and evaluated without using a cooking accelerator.

(Example 18, N material, Kraft method, cooking accelerator containing amine compound)
Cooking was performed by the Kraft method using N material as wood chips and a cooking accelerator containing a quaternary ammonium compound and an amine compound.
Example 18 was substantially the same as Example 1 except that the quaternary ammonium compound was E1, the amine compound was A4, the wood chips were N material, and the amounts of sodium sulfide pentahydrate and sodium hydroxide were changed. Digestion was performed in the same manner as before and evaluated. In Example 18, 7.75 g of sodium sulfide pentahydrate (3.6 g as pure sodium sulfide) and 12.6 g of sodium hydroxide were added to the cooking liquor.
The evaluation criteria when using the Kraft method and N material were as follows.
(1) Evaluation criteria for wood piece residual rate Excellent: wood piece residual rate less than 0.5%;
Good: The residual rate of wood pieces is 0.5% or more and less than 1.5%,
Poor: The residual rate of wood pieces is 1.5% or more and less than 2.5%,
Bad: Wood piece residual rate is 2.5% or more.
(2) Evaluation criteria for yield rate Excellent: Yield rate is 52.5% or more,
Good: Yield rate is less than 52.5%, 52.0% or more,
Poor: Yield rate is less than 52.0%, 51.5% or more,
Bad: Yield is less than 51.5% (3) Kappa number evaluation criteria Excellent: Kappa number is less than 29.0,
Good: Kappa number is 29.0 or more and less than 29.5,
Poor: Kappa number is 29.5 or more and less than 30.0,
Bad: Kappa number is 30.0 or more.

(Examples 19 to 22, Comparative Examples 18 to 26, N material, Kraft method, cooking accelerator containing amine compound)
Examples 19 to 22 and Comparative Examples 18 to 26 are the same as Example 18, except that the types, usage amounts, and mass ratios of the quaternary ammonium compound and amine compound were changed, as shown in Tables 4 and 5. Cooking was performed and evaluated using the same method as above. In addition, Comparative Example 18 was cooked and evaluated without using a cooking accelerator.

(Example 23, N material, polysulfide method, cooking accelerator containing amine compound)
Cooking was performed by the polysulfide method using N material as wood chips and a cooking accelerator containing a quaternary ammonium compound and an amine compound.
In Example 23, the quaternary ammonium compound was E1, the amine compound was A4, the wood chips were N material, the amounts of sodium sulfide pentahydrate, and sodium hydroxide were changed, and a new sodium tetrasulfide solution (Nagao Cooking was carried out and evaluated in substantially the same manner as in Example 1, except that the same procedure as in Example 1 was used. In Example 23, 6.2 g of sodium sulfide pentahydrate (2.88 g as pure sodium sulfide), 12.6 g of sodium hydroxide, and 2.4 g of sodium tetrasulfide solution (as pure sodium tetrasulfide) 0.72 g) was added to the cooking liquor.
The evaluation criteria when using the polysulfide method and N material were as follows.
(1) Evaluation criteria for wood piece residual rate Excellent: wood piece residual rate less than 0.5%;
Good: The residual rate of wood pieces is 0.5% or more and less than 1.5%,
Poor: The residual rate of wood pieces is 1.5% or more and less than 2.5%,
Bad: Wood piece residual rate is 2.5% or more.
(2) Evaluation criteria for yield rate Excellent: Yield rate is 52.5% or more,
Good: Yield rate is less than 52.5%, 52.0% or more,
Poor: Yield rate is less than 52.0%, 51.5% or more,
Bad: Yield rate is less than 51.5%.
(3) Evaluation criteria for kappa number Excellent: Kappa number is less than 29.0,
Good: Kappa number is 29.0 or more and less than 29.5,
Poor: Kappa number is 29.5 or more and less than 30.0,
Bad: Kappa number is 30.0 or more.

(Examples 24 and 25, Comparative Examples 27 to 31, N material, polysulfide method, digestion accelerator containing amine compound)
Examples 24, 25, and Comparative Examples 27 to 31 are the same as Example 23, except that the types, usage amounts, and mass ratios of the quaternary ammonium compound and amine compound were changed, as shown in Tables 6 and 7. Cooking was performed and evaluated using the same method as above. In addition, Comparative Example 27 was cooked and evaluated without using a cooking accelerator. Each evaluation was performed using the same evaluation criteria as that of Example 23.

(Example 26, L material, soda method, digestion accelerator containing amine compound)
Cooking was performed by the soda method using L wood as wood chips and a cooking accelerator containing a quaternary ammonium compound and an amine compound.
In Example 26, the quaternary ammonium compound was E1, the amine compound was A4, the wood chips were L material, only sodium hydroxide was used as the alkaline base agent, and the amount added was changed. In addition, the content of quaternary ammonium compound E1 (pure part) and amine compound A4 (pure part) is 0.06% by mass with respect to L material (wood chips), and the content of quaternary ammonium compound E1 (pure part) is 0.06% by mass. It was prepared so that the mass ratio with amine compound A4 (pure content) was 100:1. Specifically, for 50.0 g of L material (wood chips), 29.7 mg of quaternary ammonium compound E1 (purity) and 0.3 mg of amine compound A4 (purity) were placed in a container, and mixed with water. The mixture was dissolved to obtain a digestion accelerator used in Example 26. Other than that, cooking was performed and evaluated in substantially the same procedure as in Example 1. In Example 26, 16.2 g of sodium hydroxide was added to the cooking liquor.
The evaluation criteria when using the soda method and L material were as follows.
(1) Evaluation criteria for wood piece residual rate Excellent: wood piece residual rate less than 1.0%;
Good: The residual rate of wood pieces is 1.0% or more and less than 1.5%,
Poor: The residual rate of wood pieces is 1.5% or more and less than 2.5%,
Bad: Wood piece residual rate is 2.5% or more.
(2) Evaluation criteria for yield rate Excellent: Yield rate is 52.0% or more,
Good: Yield rate is less than 52.0%, 51.5% or more,
Poor: Yield rate is less than 51.5%, 51.0% or more,
Bad: Yield rate is less than 51.0%.
(3) Evaluation criteria for kappa number Excellent: Kappa number is less than 18.5,
Good: Kappa number is 18.5 or more and less than 19.0,
Poor: Kappa number is 19.0 or more and less than 19.5,
Bad: Kappa number is 19.5 or more.

(Examples 27, 28, Comparative Examples 32 to 36, L material, soda method, cooking accelerator containing amine compound)
Examples 27, 28, and Comparative Examples 32 to 36 are the same as Example 26, except that the types, usage amounts, and mass ratios of the quaternary ammonium compound and amine compound were changed, as shown in Tables 8 and 9. Cooking was performed in the same manner as in Example 26, and evaluation was made using the same evaluation criteria as in Example 26. In addition, Comparative Example 32 was cooked and evaluated without using a cooking accelerator.

(Example 29, L material, Kraft method, cooking accelerator containing sulfur-containing compound)
Cooking was performed by the Kraft method using L wood as wood chips and a cooking accelerator containing a quaternary ammonium compound and a sulfur-containing compound. The L material was passed through a stainless steel sieve with an opening of 710 μm, and the L material remaining on the sieve was dried at 60° C. for 24 hours. The digestion accelerator contains 0.03% by mass of quaternary ammonium compound E3 (pure content) and amine compound B1 (pure content) with respect to L material (wood chips), and the content of quaternary ammonium compound E3 (pure content) is 0.03% by mass. The mass ratio of sulfur-containing compound B1 (pure component) to sulfur-containing compound B1 (pure component) was 6:1. Specifically, 12.86 mg of quaternary ammonium compound E3 (purity) and 2.14 mg of sulfur-containing compound B1 (purity) were added to 50.0 g of L material (wood chips) in a container, and distilled water was added. The digestion accelerator used in Example 29 was obtained.
Next, add 6.9 g of sodium sulfide pentahydrate (3.2 g as pure sodium sulfide) and 11.2 g of sodium hydroxide to a beaker, and add distilled water so that the total mass is 145 g. An alkaline aqueous solution was obtained. The previously prepared cooking accelerator was added to this aqueous solution, and distilled water was added so that the total mass was 150 g, followed by stirring to obtain a cooking liquid.
50.0 g of the prepared L material and 150 g of the cooking liquid were placed in a pot (MINI COLOR, manufactured by Texam Giken Co., Ltd.) and cooked at 150° C. for 50 minutes.

After cooking, Example 29 was evaluated for wood piece residual rate, yield rate, and kappa number, and the results are shown in Table 10. The wood piece residual rate, yield rate, and kappa value of Example 29 were evaluated using the same evaluation criteria as those of Example 1.

(Examples 30 to 44, Comparative Examples 37 to 44, L material, Kraft method, cooking accelerator containing sulfur-containing compound)
Examples 30 to 44 and Comparative Examples 37 to 44 are the same as Examples 30 to 44, except that the types, usage amounts, and mass ratios of the quaternary ammonium compound and sulfur-containing compound were changed, as shown in Tables 10 and 11. Cooking was performed and evaluated using the same method as No. 29.
The digestion accelerator of Comparative Example 44 differed from the digestion accelerator of Example 29 in that a quaternary ammonium compound and a sulfur compound were used separately. Specifically, only 12.86 mg of quaternary ammonium compound E3 (purity) was placed in a container and dissolved in distilled water to obtain a digestion accelerator used in Comparative Example 44. Next, 2.14 mg of sulfur-containing compound B1 (pure content), which was not used in the preparation of the digestion accelerator, 6.9 g of sodium sulfide pentahydrate (3.2 g of pure sodium sulfide), and water. 11.2 g of sodium oxide was added to a beaker, and distilled water was added so that the total mass was 145 g to obtain an alkaline aqueous solution. Furthermore, the digestion accelerator prepared earlier was added to this aqueous solution, and distilled water was added so that the total mass was 150 g, followed by stirring to obtain a cooking liquid. Then, 50.0 g of L material and 150 g of cooking liquid were placed in a pot (MINI COLOR, manufactured by Texam Giken Co., Ltd.), and cooking was performed at 150° C. for 50 minutes. As mentioned above, Comparative Example 44 differs from Example 29 in that sulfur-containing compound B1 (pure content) was not used in preparing the cooking accelerator, but was used in preparing the cooking liquor. The evaluation criteria were the same as in Example 29, and the evaluation criteria in Example 1 were used.

(Example 45, N material, Kraft method, digestion accelerator containing sulfur-containing compound)
Cooking was performed by the Kraft method using N material as wood chips and a cooking accelerator containing a quaternary ammonium compound and a sulfur-containing compound.
Example 45 was essentially the same as Example 18 except that the quaternary ammonium compound was E2, the sulfur-containing compound was B1, the wood chips were N material, and the amounts of sodium sulfide pentahydrate and sodium hydroxide were changed. Digestion was performed and evaluated using the same procedure. In Example 45, 7.75 g of sodium sulfide pentahydrate (3.6 g as pure sodium sulfide) and 12.6 g of sodium hydroxide were added to the cooking liquor. The wood piece residual rate, yield rate, and kappa value of Example 45 were evaluated using the same evaluation criteria as those of Example 18.

(Examples 46 to 49, Comparative Examples 45 to 50, N material, Kraft method, cooking accelerator containing sulfur-containing compound)
Examples 46 to 49 and Comparative Examples 45 to 50 are the same as Examples 46 to 49 and Comparative Examples 45 to 50, except that the types, usage amounts, and mass ratios of the quaternary ammonium compound and sulfur-containing compound were changed, as shown in Tables 12 and 13. Cooking was performed using the same method as No. 45, and evaluation was made using the same evaluation criteria. Comparative Example 50 used a quaternary ammonium compound and a sulfur compound separately. This example differs from Example 46 in that sulfur-containing compound B2 (pure component) was not used in preparing the digestion accelerator, but sulfur-containing compound B2 (pure component) was used in preparing the cooking liquor.

(Example 50, N material, polysulfide method, digestion accelerator containing sulfur-containing compound)
Cooking was performed by the polysulfide method using N material as wood chips and a cooking accelerator containing a quaternary ammonium compound and a sulfur-containing compound.
In Example 50, the quaternary ammonium compound was E2, the sulfur-containing compound was B3, the wood chips were N material, the amounts of sodium sulfide pentahydrate and sodium hydroxide were changed, and a new sodium tetrasulfide solution ( Cooking was carried out and evaluated in substantially the same manner as in Example 23, except for using Nagao Co., Ltd.). In Example 50, 6.2 g of sodium sulfide pentahydrate (2.88 g as pure sodium sulfide), 12.6 g of sodium hydroxide, and 2.4 g of sodium tetrasulfide solution (as pure sodium tetrasulfide) 0.72 g) was added to the cooking liquor. The wood piece residual rate, yield rate, and kappa value of Example 50 were evaluated using the same evaluation criteria as those of Example 23.

(Examples 51 and 52, Comparative Examples 51 to 55, N material, polysulfide method, digestion accelerator containing sulfur-containing compound)
Examples 51, 52 and Comparative Examples 51 to 55 are the same as Examples 51 to 55, except that the types, usage amounts, and mass ratios of the quaternary ammonium compound and the sulfur-containing compound were changed, as shown in Tables 14 and 15. Cooking was performed and evaluated in the same manner as in No. 50. The wood piece residual rate, yield rate, and kappa number were evaluated using the same evaluation criteria as in Example 23.
The digestion accelerator of Comparative Example 55 differed from the digestion accelerator of Example 51 in that a quaternary ammonium compound and a sulfur compound were used separately. Specifically, only 12.86 mg of quaternary ammonium compound E4 (purity) was placed in a container and dissolved in distilled water to obtain a digestion accelerator used in Comparative Example 55. Next, 2.14 mg of sulfur-containing compound B1 (pure content), which was not used in the preparation of the digestion accelerator, 6.2 g of sodium sulfide pentahydrate (2.88 g of pure sodium sulfide), and water. 12.6 g of sodium oxide and 2.4 g of sodium tetrasulfide solution (0.72 g as pure sodium tetrasulfide) were added to a beaker, and distilled water was added so that the total mass was 145 g to obtain an alkaline aqueous solution. . Furthermore, the digestion accelerator prepared earlier was added to this aqueous solution, and distilled water was added so that the total mass was 150 g, followed by stirring to obtain a cooking liquid. Then, 50.0 g of N material and 150 g of cooking liquid were placed in a pot (MINI COLOR, manufactured by Texam Giken Co., Ltd.), and cooking was performed at 150° C. for 50 minutes. As mentioned above, Comparative Example 45 differs from Example 51 in that sulfur-containing compound B1 (pure content) was not used in preparing the cooking accelerator, but was used in preparing the cooking liquor.

(Example 53, L material, soda method, digestion accelerator containing sulfur-containing compound)
Cooking was performed by the soda method using L wood as wood chips and a cooking accelerator containing a quaternary ammonium compound and a sulfur-containing compound.
In Example 53, the quaternary ammonium compound was E2, the sulfur-containing compound was B4, the wood chips were L material, only sodium hydroxide was used as the alkaline base agent, and the amount added was changed. In addition, the content of quaternary ammonium compound E2 (pure content) and sulfur-containing compound B4 (pure content) is 0.06% by mass with respect to L material (wood chips), and the content of quaternary ammonium compound E2 (pure content) is 0.06% by mass. and sulfur-containing compound B4 (pure content) in a mass ratio of 6:1. Specifically, 25.71 mg of quaternary ammonium compound E2 (purity) and 4.29 mg of sulfur-containing compound B4 (purity) were placed in a container for 50.0 g of L material (wood chips), and the mixture was distilled. It was dissolved in water to obtain the digestion accelerator used in Example 53. Other than that, cooking was performed and evaluated using substantially the same procedure as in Example 26. 16.2 g of sodium hydroxide was added to the cooking liquor. The wood piece residual rate, yield rate, and kappa number were evaluated using the same evaluation criteria as in Example 26.

(Examples 54 and 55, Comparative Examples 56 to 61, L material, soda method, digestion accelerator containing sulfur-containing compound)
Examples 54, 55, and Comparative Examples 56 to 61 are the same as Examples 54 and 55, and Comparative Examples 56 to 61, except that the types, usage amounts, and mass ratios of the quaternary ammonium compound and the sulfur-containing compound were changed, as shown in Tables 16 and 17. Cooking was performed and evaluated using the same method as No. 53. Comparative Example 61 used a quaternary ammonium compound and a sulfur compound separately. This example differs from Example 54 in that sulfur-containing compound B2 (pure component) was not used in preparing the digestion accelerator, but sulfur-containing compound B2 (pure component) was used in preparing the cooking liquor. The wood piece residual rate, yield rate, and kappa number were evaluated using the same evaluation criteria as in Example 26.

It was found that the cooking accelerators of Examples 1 to 55 had good wood chip residual rate, yield rate, and kappa number in cooking by the Kraft method, cooking by the polysulfide method, and cooking by the soda method.

As described above, the digestion accelerator of the present invention can more efficiently digest materials containing lignocellulose.

(Additional note)
(Additional note 1)
A quaternary ammonium compound represented by formula (1),
At least one amine selected from the group consisting of a primary monoamine represented by formula (2), a secondary monoamine represented by formula (3), and a tertiary monoamine represented by formula (4) A digestion accelerator containing a compound.
In formula (1), R ¹ is an alkyl group having 8 to 22 carbon atoms, a hydroxyalkyl group having 8 to 22 carbon atoms, an alkenyl group having 8 to 22 carbon atoms, or a hydroxyalkenyl group having 8 to 22 carbon atoms. ,
R ² is an alkyl group having 1 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or (A ¹ O) _n Y is the basis,
R ³ and R ⁴ each independently represent an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, Aryl group, benzyl group which may have an alkyl group having 1 to 4 carbon atoms, phenethyl group which may have an alkyl group having 1 to 4 carbon atoms, glycidyl group, or (A ¹ O) _m Y is the basis,
N represents a nitrogen atom,
X ^p- represents a counter ion, is an inorganic anion or an organic anion, p represents the valence of the ion,
A ¹ O is an alkyleneoxy group having 2 to 4 carbon atoms, Y is a hydrogen atom or an acyl group,
n is an integer from 1 to 15, and m is an integer from 1 to 15.
In formula (2), R ⁵ is an alkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or ( A ² O) _k Z group, A ² O is an alkyleneoxy group having 2 to 4 carbon atoms, Z is a hydrogen atom or an acyl group, and k is an integer of 1 to 6.
In formula (3), R ⁶ and R ⁷ each independently represent an alkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, or a hydroxyalkyl group having 2 to 22 carbon atoms. 22 hydroxyalkenyl group or (A ³ O) _r Z group, A ³ O is an alkyleneoxy group having 2 to 4 carbon atoms, Z is a hydrogen atom or an acyl group, and r is 1 It is an integer between ~12.
In formula (4), R ⁸ and R ⁹ each independently represent an alkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, or a hydroxyalkyl group having 2 to 22 carbon atoms. 22 hydroxyalkenyl group or (A ⁴ O) _t Z group, A ⁴ O is an alkyleneoxy group having 2 to 4 carbon atoms, Z is a hydrogen atom or an acyl group, and t is 1 ~12 integers,
R ¹⁰ is an alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, or (A ⁵ O) _u Z A ⁵ O is an alkyleneoxy group having 2 to 4 carbon atoms, Z is a hydrogen atom or an acyl group, and u is an integer of 1 to 12.

(Additional note 2)
The digestion accelerator according to Supplementary Note 1, wherein the mass ratio of the quaternary ammonium compound and the amine compound is 5:1 to 10,000:1.

(Additional note 3)
A quaternary ammonium compound represented by formula (1),
A sulfur-containing compound that generates sulfide ions, polysulfide ions, or hydrogen sulfide ions in the presence of the quaternary ammonium compound.
In formula (1), R ¹ is an alkyl group having 8 to 22 carbon atoms, a hydroxyalkyl group having 8 to 22 carbon atoms, an alkenyl group having 8 to 22 carbon atoms, or a hydroxyalkenyl group having 8 to 22 carbon atoms. ,
R ² is an alkyl group having 1 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or (A ¹ O) _n Y is the basis,
R ³ and R ⁴ each independently represent an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, Aryl group, benzyl group which may have an alkyl group having 1 to 4 carbon atoms, phenethyl group which may have an alkyl group having 1 to 4 carbon atoms, glycidyl group, or (A ¹ O) _m Y is the basis,
N represents a nitrogen atom,
X ^p- represents a counter ion, is an inorganic anion or an organic anion, p represents the valence of the ion,
A ¹ O is an alkyleneoxy group having 2 to 4 carbon atoms, Y is a hydrogen atom or an acyl group,
n is an integer from 1 to 15, and m is an integer from 1 to 15.

(Additional note 4)
The sulfur-containing compounds include thiosulfates, bithiosulfates, sulfites, bisulfites, disulphites, dithionites, dithionates, disulfates, peroxosulfates, peroxodisulfates, and polythiones. The digestion accelerator according to Supplementary note 3, which is composed of at least one compound selected from the group consisting of acid salts.

(Appendix 5)
The digestion accelerator according to appendix 3 or 4, wherein the mass ratio of the quaternary ammonium compound and the sulfur-containing compound is 1:2 to 100:1.

(Appendix 6)
A method for producing pulp, comprising a cooking step of cooking a material containing lignocellulose by adding at least one base agent selected from the group consisting of an alkaline base agent and a sulfite base agent, and a digestion accelerator,
A method for producing pulp, wherein the digestion accelerator is the digestion accelerator according to any one of Supplementary Notes 1 to 5.

(Appendix 7)
The method for producing pulp according to appendix 6, wherein the content of the digestion accelerator is 0.001% by mass to 1.0% by mass based on the material containing the lignocellulose.

The present invention is capable of various embodiments and modifications without departing from the broad spirit and scope of the present invention. Moreover, the embodiments described above are for explaining the present invention, and do not limit the scope of the present invention. That is, the scope of the present invention is indicated by the claims rather than the embodiments. Various modifications made within the scope of the claims and within the meaning of the invention equivalent thereto are considered to be within the scope of this invention.

This application is based on a Japanese patent application, Japanese Patent Application No. 2022-106468, filed on June 30, 2022. The entire specification and claims of the Japanese patent application, Japanese Patent Application No. 2022-106468, are incorporated herein by reference.

Claims

A quaternary ammonium compound represented by formula (1),
At least one amine selected from the group consisting of a primary monoamine represented by formula (2), a secondary monoamine represented by formula (3), and a tertiary monoamine represented by formula (4) A digestion accelerator containing a compound.
In formula (1), R 1 is an alkyl group having 8 to 22 carbon atoms, a hydroxyalkyl group having 8 to 22 carbon atoms, an alkenyl group having 8 to 22 carbon atoms, or a hydroxyalkenyl group having 8 to 22 carbon atoms. ,
R 2 is an alkyl group having 1 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or (A 1 O) n Y is the basis,
R 3 and R 4 each independently represent an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, Aryl group, benzyl group which may have an alkyl group having 1 to 4 carbon atoms, phenethyl group which may have an alkyl group having 1 to 4 carbon atoms, glycidyl group, or (A 1 O) m Y is the basis,
N represents a nitrogen atom,
X p- represents a counter ion, is an inorganic anion or an organic anion, p represents the valence of the ion,
A 1 O is an alkyleneoxy group having 2 to 4 carbon atoms, Y is a hydrogen atom or an acyl group,
n is an integer from 1 to 15, and m is an integer from 1 to 15.
In formula (2), R 5 is an alkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or ( A 2 O) k Z group, A 2 O is an alkyleneoxy group having 2 to 4 carbon atoms, Z is a hydrogen atom or an acyl group, and k is an integer of 1 to 6.
In formula (3), R 6 and R 7 each independently represent an alkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, or a hydroxyalkyl group having 2 to 22 carbon atoms. 22 hydroxyalkenyl group or (A 3 O) r Z group, A 3 O is an alkyleneoxy group having 2 to 4 carbon atoms, Z is a hydrogen atom or an acyl group, and r is 1 It is an integer between ~12.
In formula (4), R 8 and R 9 each independently represent an alkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, or a hydroxyalkyl group having 2 to 22 carbon atoms. 22 hydroxyalkenyl group or (A 4 O) t Z group, A 4 O is an alkyleneoxy group having 2 to 4 carbon atoms, Z is a hydrogen atom or an acyl group, and t is 1 ~12 integers,
R 10 is an alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, or (A 5 O) u Z A 5 O is an alkyleneoxy group having 2 to 4 carbon atoms, Z is a hydrogen atom or an acyl group, and u is an integer of 1 to 12.
The digestion accelerator according to claim 1, wherein the mass ratio of the quaternary ammonium compound and the amine compound is 5:1 to 10,000:1.
A quaternary ammonium compound represented by formula (1),
A sulfur-containing compound that generates sulfide ions, polysulfide ions, or hydrogen sulfide ions in the presence of the quaternary ammonium compound.
In formula (1), R 1 is an alkyl group having 8 to 22 carbon atoms, a hydroxyalkyl group having 8 to 22 carbon atoms, an alkenyl group having 8 to 22 carbon atoms, or a hydroxyalkenyl group having 8 to 22 carbon atoms. ,
R 2 is an alkyl group having 1 to 22 carbon atoms, a hydroxyalkyl group having 1 to 22 carbon atoms, an alkenyl group having 2 to 22 carbon atoms, a hydroxyalkenyl group having 2 to 22 carbon atoms, or (A 1 O) n Y is the basis,
R 3 and R 4 each independently represent an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, a hydroxyalkenyl group having 2 to 4 carbon atoms, Aryl group, benzyl group which may have an alkyl group having 1 to 4 carbon atoms, phenethyl group which may have an alkyl group having 1 to 4 carbon atoms, glycidyl group, or (A 1 O) m Y is the basis,
N represents a nitrogen atom,
X p- represents a counter ion, is an inorganic anion or an organic anion, p represents the valence of the ion,
A 1 O is an alkyleneoxy group having 2 to 4 carbon atoms, Y is a hydrogen atom or an acyl group,
n is an integer from 1 to 15, and m is an integer from 1 to 15.
The sulfur-containing compounds include thiosulfates, bithiosulfates, sulfites, bisulfites, disulphites, dithionites, dithionates, disulfates, peroxosulfates, peroxodisulfates, and polythiones. The digestion accelerator according to claim 3, comprising at least one compound selected from the group consisting of acid salts.
The digestion accelerator according to claim 3 or 4, wherein the mass ratio of the quaternary ammonium compound and the sulfur-containing compound is 1:2 to 100:1.
A method for producing pulp, comprising a cooking step of cooking a material containing lignocellulose by adding at least one base agent selected from the group consisting of an alkaline base agent and a sulfite base agent, and a digestion accelerator,
A method for producing pulp, wherein the digestion accelerator is the digestion accelerator according to claim 1 or 3.
The method for producing pulp according to claim 6, wherein the content of the digestion accelerator is 0.001% by mass to 1.0% by mass based on the material containing the lignocellulose.