JP2962850B2 - Deinking agent and deinking method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deinking agent and a deinking method used for recycling waste paper such as newspapers, magazines, and OA waste paper. More specifically, when performing deinking treatment of newspapers, magazines, OA waste paper, etc. by a flotation method, a washing method or a compromise method thereof, obtaining deinked pulp having a high whiteness, a high b value and a small amount of unstripped ink. And a deinking method.

[0002]

BACKGROUND OF THE INVENTION Newspapers,
Recycling of magazines, OA waste paper, and the like has been practiced for a long time, but recently, in conjunction with global environmental issues such as protection of forest resources and garbage disposal, the effective use of waste paper is increasing in importance. In addition, the use of deinked pulp has been advanced to higher-grade pulp as seen in the example of used newspaper to medium-grade paper. On the other hand, recently used paper is becoming more severe from the viewpoint of deinking due to changes in printing technology, printing method, printing ink components, and the like. Therefore, in order to further promote deinking, improvements have been made to the apparatus. Chemicals conventionally used to separate and remove ink and other impurities from waste paper include alkaline agents such as caustic soda, sodium silicate, sodium carbonate, and sodium phosphate, hydrogen peroxide, hyposulfite, and hypochlorous acid. Bleaching agents such as salts, sequestering agents such as EDTA and DTPA, and anionic surfactants such as alkylbenzene sulfonates, higher alcohol sulfates, α-olefin sulfonates, and dialkyl sulfosuccinates as deinking agents. Nonionic activators such as ethylene oxide adducts of higher alcohols, alkylphenols and fatty acids, and alkanolamides have been used alone or in combination of two or more. However, these deinking agents have a high foaming property in the flotation process, but have a low ink collecting ability.The cleaning method has a low detergency. And resulted in only low grade deinked pulp. Especially PPC (plain paper copy), CPO
OA waste paper represented by (computer print output) uses a styrene / acrylic binder or polyester binder whose printing ink (toner) is different from the printing ink binder for newspapers. After the cleaning, coarse ink having a particle size of 30 μm or more remains without being removed, so that a large amount of shearing energy must be applied or a large amount of alkalis must be used. However, this method is sticky (sticky)
However, there is a drawback in that OA waste paper and pulp are embrittled, and there is no effective means for deinking OA waste paper and its blends.

[0003]

Means for Solving the Problems The present inventors have demonstrated excellent ink removing ability in a flotation method, a washing method and a compromise method thereof, no foaming trouble, and a high whiteness when various kinds of used paper are used. You can get deinked pulp
In particular, when OA waste paper and its blends are used, a deinking agent and a deinking agent having an effect of reducing a coarse ink having a particle diameter of 30 μm or more without using a large amount of shear energy and without using a large amount of alkalis. As a result of intensive research to develop a method, surprisingly, a deinking agent containing a specific nonionic activator as an essential component, and this deinking agent is dividedly added to the pulping step and the subsequent steps. The inventors have found that the deinking method can overcome the above-mentioned disadvantages, and have reached the present invention.

That is, the present invention relates to a compound obtained by adding an alkylene oxide to a polyfunctional alcohol or fatty acid having 1 to 10 carbon atoms in an amount of 1 to 4 mol per functional group (however, the total number of added mols is 22 mol or less). And 2 to 8 carbon atoms
A deinking agent containing as an essential component a compound which is a partially esterified product with a fatty acid and having a solubility parameter value in the range of 8.9 to 9.8, and a process after the pulping step (pre-step) and the pulping step The present invention provides a deinking method characterized by being dividedly added to (post-process).

The present invention provides a deinking agent containing, as an essential component, a partially esterified product of an alkylene oxide adduct of a polyfunctional alcohol or polyfunctional fatty acid having 1 to 10 carbon atoms and a fatty acid having 2 to 8 carbon atoms. Things. The term "polyfunctional" as used herein means that the number of functional groups having active hydrogen is two or more. Specific examples of the polyfunctional alcohol having 1 to 10 carbon atoms used as a raw material include ethylene glycol, trimethylene glycol, 1,4-butanediol, 1,5-
Pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,2-octanediol, 1,2-decane Diol, butanoyl-α-glycol, 1,3-butanediol, trans-2-butene-
1,4-diol, 2-butyne-1,4-diol, 2,4-
Pentanediol, 2,5-hexanediol, 2-methyl-1,3-pentanediol, 2-methyl-2,4-pentanediol, 2,3-dimethyl-2,3-butanediol, 2,4-heptane Diol, 2,2-diethyl-1,3-
Propanediol, 2-ethyl-1,3-hexanediol, 2-ethyl-2-butyl-1,3-propanediol, diethylene glycol, triethylene glycol,
Tetraethylene glycol, dipropylene glycol,
1,2-cyclononanediol, 1,2-cyclodecanediol, glycerin, erythrit, pentaerythritol, arabbit, sorbit, sorbitan, mannitol, mannitan, 1,2,3-butanetriol, 2-methylpropane-1 , 2,3-butanetriol, 2-methylpropane-1,2,3-triol, 2,3,4-pentanetriol, 2-methylbutane-1,2,3-triol, 2,3,4
-Hexanetriol, 2-ethylbutane-1,2,3-triol, 2,3,4-trimethylpentane-2,3,4-triol, D-glycero-D-galaheptose, D-glycero-D-glucoheptose, D -Glycero-D-mannoheptose, D-glycero-L-mannoheptose,
D-glycero-D-galaheptitol, D-altroheptulose, D-altro-3-heptulose, D-mannoheptulose, D-erythro-D-galactitol, D-glycero-D-mannooctulose , D-erythro-L-grononulose and the like.

The polyfunctional fatty acids having 1 to 10 carbon atoms used in the present invention include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, ethyl Malonic acid, 2-
Hydroxyvaleric acid, 2-hydroxycaproic acid, 2-hydroxycaprylic acid, 2-hydroxypelargonic acid, 2
-Hydroxyundecanoic acid, 3-hydroxycaprylic acid, 3-hydroxypelargonic acid, 3-hydroxycapric acid, 6-hydroxycaproic acid, 7-hydroxyenanthic acid, 8-hydroxycaprylic acid, 9-hydroxypelargonic acid, 10-hydroxy Capric acid, 2-methyl-hydroxyenanthic acid, 2-hydroxy-3-pentenoic acid, 5-hydroxy-2,4-pentadienoic acid, 2,3-
Dihydroxycaproic acid, 2,3-dihydroxyenanthic acid, 2,3-dihydroxycaprylic acid, 2,3-dihydroxypelargonic acid, 2,3-dihydroxycapric acid, 1-
Examples include nonene-1,9-dicarboxylic acid, 2-nonene-1,9-dicarboxylic acid, 1-decene-1,10-dicarboxylic acid, and 2-decene-1,10-dicarboxylic acid.

Among them, particularly preferred are those having 1 to 1 carbon atoms.
The polyfunctional alcohol and the polyfunctional fatty acid are preferably a saturated polyfunctional alcohol and a polyfunctional fatty acid having 1 to 3 carbon atoms.

The alkylene oxide added to the polyfunctional alcohol or fatty acid is ethylene oxide (hereinafter referred to as ethylene oxide).
EO), propylene oxide (hereinafter abbreviated as PO),
Butylene oxide (hereinafter abbreviated as BO) can be used alone or as a mixture. Particularly preferred are EO, PO and mixtures thereof. The method of adding the alkylene oxide may be any of random addition and block addition, but random addition is particularly preferable in consideration of foaming troubles in the papermaking process and the wastewater treatment process.

The fatty acids having 2 to 8 carbon atoms used for producing such partially esterified products include acetic acid, propionic acid, propic acid, butyric acid, isobutyric acid, tetrolic acid, valeric acid, α-methylbutyric acid, Valeric acid, trimethylpropanoic acid, 2-pentynic acid, allylacetic acid, 2,4
-Pentadienoic acid, caproic acid, 2-methylpentanoic acid, 3-methylpentanoic acid, 4-isocaproic acid, 2-
Hexic acid, sorbic acid, 2-hexenoic acid, 3-hexenoic acid, 4-hexanoic acid, 5-hexenoic acid, heptanoic acid,
2-heptenoic acid, 3-heptenoic acid, 5-heptenoic acid, 6
-Heptenoic acid, 2-heptic acid, 6-heptic acid, caprylic acid, 2-ethylhexanoic acid, 2-octenoic acid, 3-
Octenoic acid, 2-octic acid, 7-octic acid, 2-methyl-2-heptenoic acid, benzoic acid, methylbenzoic acid, cyclohexylacetic acid, 2-fluorovaleric acid, 2-fluorocaproic acid, 2-fluoroenanoic acid, 2-chlorocaprylic acid, 2-bromovaleric acid, 2-bromocaproic acid, 2
-Bromoenanthic acid, 2-bromocaprylic acid, 5-chlorovaleric acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, ethylmalonic acid, 2-hydroxyvaleric acid, 2-hydroxy Caproic acid, 2-hydroxycaprylic acid, 2-hydroxypelargonic acid, 2-hydroxyundecanoic acid, 3-hydroxycaprylic acid, 6-hydroxycaproic acid, 7-hydroxyenanthic acid, 8-hydroxycaprylic acid, 2-methyl-hydroxy Enanthic acid, 2-hydroxy-3-pentenoic acid, 4-hydroxy-3-pentenoic acid, 4-hydroxy-4-pentenoic acid, 5-hydroxy-2,4-pentadienoic acid, 2,3-dihydroxycaproic acid, 2 2,3-dihydroxyenanthic acid, 2,3-dihydroxycaprylic acid, and acid anhydrides thereof. I can do it. Particularly preferred are fatty acids having 2 to 4 carbon atoms, and more preferred are saturated fatty acids.

It is very important to limit the number of carbon atoms and the physicochemical constants of the compounds according to the present invention. Cannot be obtained. As will be apparent from the examples described below, if the carbon number of the polyfunctional alcohol or polyfunctional fatty acid exceeds 10, high foaming properties cause foam trouble in the wastewater treatment step, and the productivity of deinked pulp is significantly reduced. I do. It is important that the number of moles of the alkylene oxide added is 1 to 4 per functional group. When the number of moles of the alkylene oxide added is less than 1, coarse ink having a particle size of 30 μm or more remains remarkably, and when it exceeds 4, high foaming properties cause frequent foaming troubles in the wastewater treatment step.

When the number of carbon atoms of the fatty acid constituting the partially esterified product of the alkylene oxide adduct of the polyfunctional alcohol or the polyfunctional fatty acid is smaller than 2, the residual of the coarse ink increases, and when the carbon number exceeds 8, the ink becomes high. Due to the foaming properties, problems such as foaming troubles in the wastewater treatment process occur. Further, it is important that the esterification rate of the partially esterified product is in the range of 15 to 75 mol%. Esterification rate of 15
If it is less than mol%, a large amount of coarse ink having a particle size of 30 μm or more remains in large quantities, so that its use tends to be limited (reduction in carbon number and blending amount below the surface of paperboard). On the other hand, if the esterification ratio exceeds 75 mol%, the ink becomes too fine, and it becomes difficult to obtain a deinked pulp having a high whiteness.

By using a compound having a numerical value defined in the present invention, it is possible to obtain a high-quality deinked pulp which does not cause operational trouble, has high whiteness, and has little residual coarse ink having a particle diameter of 30 μm or more. .

The present inventors have also conducted intensive studies to further improve the deinking properties of OA waste paper and its blends, and surprisingly found that compounds having a certain range of solubility parameter values were found. It has been found that it is excellent in reducing coarse ink having a particle size of 30 μm or more.

In the present invention, the solubility parameter value of the partially esterified product is 8.9 to 9.8, preferably 9.1 to 9.7.
And more preferably in the range of 9.2 to 9.5. When the solubility parameter value is smaller than the lower limit of the above range, only deinked pulp having a large amount of coarse ink can be obtained. On the other hand, if it is larger than the upper limit of the above range, the ink is too fine, and the ink cannot be sufficiently removed in the flotation step. As a result, only deinked pulp with low whiteness can be obtained, and the bubble removal property of the flotation reject is poor. Problems such as foaming trouble in the wastewater treatment process also occur.

The solubility parameter value referred to herein is Hild
It is a physicochemical constant defined from the regular solution theory established by ebrand. Whether or not the two substances dissolve is determined by the mixing free energy ΔG defined by the following equation. ΔG = ΔH−TΔS If this ΔG is negative, it indicates that the substance is dissolved, and this ΔG is expressed as a function of the solubility parameter value. Speaking from regular solution theory, the molar free energy of mixing .DELTA.G _{is, ΔG = RT (X 1 lnX} 1 + X 2 lnX 2) + V 1 X 1 φ 2 2 (δ 1 -δ 2) 2 + V 2 X 2 φ 1 2 ( δ ₁ −δ ₂ ) ² , where X ₁ and X ₂ are the mole fractions of components 1 and 2, respectively, V _i is the molar volume, φ _i is the volume fraction, and δ _i is the solubility parameter value .

In the present invention, the method of the addition reaction of the alkylene oxide is not particularly limited, and the addition reaction can be carried out under the conditions of a generally performed addition reaction of an alkylene oxide to a compound having active hydrogen. That is, a catalytic amount of an alkali substance is added to the polyfunctional alcohol or polyfunctional fatty acid according to the present invention, and the resulting mixture is added at about 100 to 200 ° C.,
It can be achieved by reacting the alkylene oxide for several hours at kg / cm ² (gauge).

As prior art, JP-A-52-81107, JP-A-55-51891, JP-A-55-51892, JP-A-56-79795, and JP-A-58-109696. The compounds described in the official gazette and JP-A-1-266292 are not polyfunctional compounds according to the present invention, but are monofunctional compounds (one active hydrogen), and do not have the effect of the present invention. JP-A-59-137588 and JP-A-64-40690 show examples of special alkylene oxide adducts of polyfunctional alcohols, but the chemical structure of the compound is entirely an aryl group or an aromatic compound. Which is clearly different from the compounds of the present invention. Further, JP-A-1-266292 states that an ether-type activator is effective as a deinking agent for OA waste paper, but its chemical structure is clearly different from that of the compound of the present invention.

The deinking agents of the present invention include known deinking agents such as higher alcohol sulfates, alkylbenzene sulfonates, ethylene oxide adducts of higher alcohols and alkyl phenols, fatty acids and salts thereof, fatty acid alkylene oxide adducts, oils and fats. Excellent deinking performance is exhibited when used in combination with an alkylene oxide adduct or the like. The combination ratio of the deinking agent of the present invention to the conventionally known deinking agent is the former / the latter = 90/10 to 10/90 (weight ratio), particularly preferably 20/80.
~ 60/40.

In general, the deinking agent is added to one or both of a mixing step including a pulping step, a kneading step, a dispersing step, a chemical mixing step and a refining step, or a floatation step.

On the other hand, in the deinking method of the present invention, the above-mentioned deinking agent according to the present invention is dividedly added to the pulping step (pre-step) in the mixing step and the steps after the pulping step (post-step). The deinking method is characterized in that

The ratio at which the deinking agent is dividedly added is 10/90 to 90/10 (weight ratio) in the pulping step (pre-step) and in the steps after the pulping step (post-step). It is preferably, particularly preferably, 40/60 to 60/40. The deinking agent of the present invention can be added all at once, or can be added separately in a later step.

The amount of the deinking agent of the present invention is desirably in an economical range without impairing the operability.
0.03 to 1.0% by weight is preferred.

[0023]

EXAMPLES The present invention will now be described specifically with reference to Production Examples and Examples, but the present invention is not limited thereto.

Production Example 1 Ethylene glycol 2 was added to a 1.5 liter autoclave.
60.1 g and 4.7 g of 100% KOH were charged, and the temperature was raised to 150 ° C. under the condition of a stirring speed of about 600 rpm. Next, 730.2 g of propylene oxide was reacted at a temperature of 120 ° C. to 130 ° C. under a pressure of 1 to 3 kg / cm ² (gauge). After the completion of the addition reaction, the mixture was cooled to 80 ° C., and the pH was adjusted to about 6 with acetic acid. The yield of the reaction product was 99%. A 1.5 liter autoclave was charged with 804.2 g of the obtained compound, 194.5 g of 2-ethylhexanoic acid and 1.2 g of 100% NaOH as a catalyst, and reacted at 230 ° C. under a nitrogen atmosphere at a stirring speed of about 500 rpm. . Reaction product (product of the present invention, No. 2 in Table 3)
The yield of 7) was 99%.

Example 1 This example is an example of the divisional addition of the deinking agent in the pulping step and the dispersing step. A binder a polyester-based printing ink, the amount of printing ink of 3.0 g / m ² CP
O Used paper (100%) is cut into 2 x 5 cm pieces, and a certain amount is put into a tabletop disintegrator, in which water and caustic soda (based on raw material)
0.3% and 0.1% of a deinking agent (relative to the raw material) shown in Table 1 were added. The pulp concentration was 15%, the mixture was disintegrated at 45 ° C for 20 minutes, and then aged at 55 ° C for 120 minutes. After that, dehydrate to 22% by high-speed dehydrator, 0.7% of caustic soda (based on raw material), 1.0% of sodium silicate 3 (based on raw material), 1.5% of 30% hydrogen peroxide (based on raw material),
After adding 0.1% of the deinking agent (relative to the raw material) shown in Table 1, desparging treatment was performed with a lab de-sparser at a rotation speed of 300 rpm. Then, add water to dilute to 4%, and disintegrate again for 30 seconds using a tabletop disintegrator. After diluting the slurry to 1% with water, it was subjected to a flotation treatment at 30 ° C. for 10 minutes.
The pulp slurry after flotation was concentrated to 4% concentration with an 80 mesh wire, and then diluted to 1% concentration by adding water, and a pulp sheet was prepared using a tappy standard paper machine. The whiteness of the obtained pulp sheet was measured by a colorimeter and the number of inks having a particle diameter of 30 μm or more was measured by an image analyzer (× 100). Further, the defoaming property of the flotation reject was used as a measure of foam trouble in the wastewater treatment process. Table 2 shows the deinking performance of various deinking agents. If the value of the defoaming property is large, it indicates that there is a high possibility of causing a foam trouble in the wastewater treatment process. The defoaming property of the flotation reject here is represented by the following equation.

[0026]

(Equation 1)

[0027]

[Table 1]

[0028]

[Table 2]

[0029]

[Table 3]

Example 2 This example is an example of the addition of the deinking agent in the pulping step and the kneading step separately. The printing ink binder is styrene acrylic, and the printing ink amount is 3.2 g / m ² PP
C Used paper (100%) is cut into 2 x 5 cm pieces, and a certain amount is put into a tabletop disintegrator, in which water and caustic soda (based on raw material)
0.3%, a predetermined amount of the deinking agent shown in Table 3 was added, and a pulp concentration of 5
%, Separated at 20 ° C for 20 minutes, and then aged at 45 ° C for 60 minutes. After that, dehydrate to 22% by high-speed dehydrator, 0.2% of caustic soda (based on raw material), 1.0% of sodium silicate 3 (based on raw material)
%, 30% hydrogen peroxide (based on raw material), 1.0%, and a predetermined amount of a deinking agent shown in Table 3 were added, and kneading was performed using a biaxial lab kneader at a rotation speed of 200 rpm. Then add water and add 4
%, And disintegrate again for 30 seconds using a desktop disintegrator. After diluting the slurry to 1% with water, it was subjected to a flotation treatment at 30 ° C. for 10 minutes. The pulp slurry after flotation was concentrated to 4% concentration with an 80 mesh wire, and then diluted to 1% concentration by adding water, and a pulp sheet was prepared using a tappy standard paper machine. The whiteness of the obtained pulp sheet was measured with a colorimeter and a colorimeter.
Times), the number of inks having a particle diameter of 30 μm or more was measured. Further, the defoaming property of the flotation reject was determined in the same manner as in Example 1, and was used as a guide for the foam trouble in the wastewater treatment step.
Table 4 shows the deinking performance of various deinking agents.

[0031]

[Table 4]

[0032]

[Table 5]

As shown above, the present invention has 1 to 10 carbon atoms.
Partially esterified compound of a compound obtained by adding 1 to 4 moles of alkylene oxide per functional group (however, the total number of added moles is 22 moles or less) to a polyfunctional alcohol or a polyfunctional fatty acid and a fatty acid having 2 to 8 carbon atoms By using a deinking agent containing a compound having a solubility parameter value in the range of 8.9 to 9.8 as an essential component when deinking OA waste paper or a blend thereof, whiteness is improved, coarse ink is reduced, In defoaming of flotation reject,
Demonstrates excellent effects.

Further, by adding the deinking agent of the present invention to the pulping step and the subsequent steps, it is possible to obtain higher quality deinked pulp.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) D21C 5/02

Claims (4)

(57) [Claims] An alkylene oxide is added to a polyfunctional alcohol or fatty acid having 1 to 10 carbon atoms per functional group.
A compound obtained by adding 4 moles (but the total number of added moles is 22 moles or less) and a fatty acid having 2 to 8 carbon atoms and having a solubility parameter value in the range of 8.9 to 9.8 as an essential component Deinking agent contained. 2. A partially esterified product having a partial esterification rate of 15
The deinking agent according to claim 1, wherein the amount is from 75 to 75 mol%. 3. The deinking agent according to claim 1 or 2, wherein the pulping step (pre-step) and the steps after the pulping step (post-step).
A deinking method characterized by being dividedly added to the ink. 4. The ratio of the deinking agent added to the pre-process / post-process = 10 /
4. The deinking method according to claim 3, wherein the ratio is 90 to 90/10 (weight ratio).