JPH05186989A - Method for bleaching cellulose pulp - Google Patents
Method for bleaching cellulose pulpInfo
- Publication number
- JPH05186989A JPH05186989A JP1947392A JP1947392A JPH05186989A JP H05186989 A JPH05186989 A JP H05186989A JP 1947392 A JP1947392 A JP 1947392A JP 1947392 A JP1947392 A JP 1947392A JP H05186989 A JPH05186989 A JP H05186989A
- Authority
- JP
- Japan
- Prior art keywords
- pulp
- bleaching
- cellulose pulp
- present
- oxygen
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Paper (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明はセルロースパルプの漂白
方法に関する。FIELD OF THE INVENTION The present invention relates to a method for bleaching cellulose pulp.
【０００２】[0002]
【従来の技術】セルロースパルプは多くの用途がある
が、クラフトパルプでの包装資材のような白色度を要求
されない用途を除いては、通常、塩素、次亜塩素酸、酸
素、過酸化水素等を用いて漂白する必要がある。近年塩
素系漂白は、生成する廃水等の公害問題等から酸素漂白
への変更が検討されている。しかし酸素漂白はパルプの
白色度が上がらず、また高圧酸素を使用すれば白色度は
向上するがセルロースの解重合が促進されパルプの強度
が低下する。従来、酸素漂白時に助剤を添加し効率を向
上させる方法（例えば特開昭５０−９４２０２号公報）
や酸素漂白時に助剤を添加し次いで次亜塩素酸で処理す
る方法（特開昭５９−１７９８９２号公報）等が提案さ
れている。2. Description of the Related Art Cellulose pulp has many uses, but normally, chlorine, hypochlorous acid, oxygen, hydrogen peroxide, etc. are used, except for uses which do not require whiteness such as packaging materials for kraft pulp. Need to be bleached with. In recent years, chlorine-based bleaching is being considered for change to oxygen bleaching due to pollution problems such as generated wastewater. However, oxygen bleaching does not increase the whiteness of the pulp, and the use of high-pressure oxygen improves the whiteness but accelerates the depolymerization of cellulose and reduces the strength of the pulp. Conventionally, a method of improving the efficiency by adding an auxiliary agent during oxygen bleaching (for example, JP-A-50-94202).
A method has been proposed in which an auxiliary agent is added during oxygen bleaching and then treated with hypochlorous acid (JP-A-59-179892).
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、これら
の方法は酸素漂白でのパルプの白色度と強度が不十分で
ある。However, these methods have insufficient whiteness and strength of pulp in oxygen bleaching.
【０００４】本発明者らは、上記の問題点を解決すべく
鋭意検討した結果、本発明に到達した。即ち、本発明は
セルロースパルプのアルカリ性水スラリーを、酸素ガス
および／または過酸化物で処理する方法において、アミ
ンのアシル化物（Ａ）の存在下で処理することを特徴と
するセルロースパルプの漂白方法である。The present inventors have arrived at the present invention as a result of extensive studies to solve the above problems. That is, the present invention is a method for bleaching a cellulose pulp, which comprises treating an alkaline water slurry of cellulose pulp with oxygen gas and / or peroxide in the presence of an acylated product (A) of an amine. Is.
【０００５】[0005]
【課題を解決するための手段】本発明において、（Ａ）
を構成するアミンとしては、下記（１）〜（４）等のア
ミンが挙げられる。In the present invention, (A)
Examples of the amine constituting the above include amines such as the following (1) to (4).
【０００６】（１）モノアミン（アンモニア、アニリ
ン、ｐ−トルイジン、アミノフェノール等） （２）ジアミン（メチレンジアミン、エチレンジアミ
ン、ジアミノベンゼン等） （３）トリアミン（ジエチレントリアミン、トリアミノ
ベンゼン等） （４）ポリアミン（ポリアルキレンポリアミン、ポリア
ルキレンポリアミンの尿素縮合物等）(1) Monoamine (ammonia, aniline, p-toluidine, aminophenol, etc.) (2) Diamine (methylenediamine, ethylenediamine, diaminobenzene, etc.) (3) Triamine (diethylenetriamine, triaminobenzene, etc.) (4) Polyamine (Polyalkylene polyamine, urea condensate of polyalkylene polyamine, etc.)
【０００７】本発明において、（Ａ）を構成するアシル
基としては、ホルミル基、炭素数が１から３０の脂肪族
カルボン酸から誘導されるアシル基およびジアシル基、
ベンゾイル基等が挙げられ、好ましいものはアセチル基
である。In the present invention, as the acyl group constituting (A), a formyl group, an acyl group and a diacyl group derived from an aliphatic carboxylic acid having 1 to 30 carbon atoms,
Examples thereof include a benzoyl group, and the preferable one is an acetyl group.
【０００８】本発明において、（Ａ）の具体例として
は、トリアセチルアミン、トリプロピオニルアミン、ジ
アセチルアニリン、ジアセチル−ｐ−トルイジン、テト
ラアセチルメチレンジアミン、テトラプロピオニルメチ
レンジアミン、テトラアセチルエチレンジアミン、テト
ラプロピオニルエチレンジアミン、ペンタアセチルジエ
チレントリアミン、ペンタプロピオニルジエチレントリ
アミン、ポリアルキレンポリアミンと脂肪酸のアミド、
ポリアルキレンポリアミンと脂肪酸のアミドを尿素で縮
合した物等であり、好ましくはテトラアセチルエチレン
ジアミンである。In the present invention, specific examples of (A) include triacetylamine, tripropionylamine, diacetylaniline, diacetyl-p-toluidine, tetraacetylmethylenediamine, tetrapropionylmethylenediamine, tetraacetylethylenediamine, tetrapropionylethylenediamine. , Pentaacetyldiethylenetriamine, pentapropionyldiethylenetriamine, amides of polyalkylenepolyamines and fatty acids,
A product obtained by condensing a polyalkylenepolyamine and an amide of a fatty acid with urea, etc., and preferably tetraacetylethylenediamine.
【０００９】本発明において、（Ａ）の添加量は、漂白
後の白色度に対する要求等により一律には決められない
為限定するものではないが、パルプ懸濁液に対して絶乾
パルプ重量当り0.01〜10重量％である。添加量が、0.01
重量％未満であると十分な効果が得られず、10重量％を
越えると漂白効果が平衡に達する。In the present invention, the amount of (A) added is not limited because it cannot be uniformly determined due to requirements for whiteness after bleaching, etc. 0.01 to 10% by weight. Addition amount is 0.01
If it is less than 10% by weight, a sufficient effect cannot be obtained, and if it exceeds 10% by weight, the bleaching effect reaches equilibrium.
【００１０】これらの（Ａ）が、漂白水溶液への溶解度
が低い場合は、界面活性剤などの可溶化剤、乳化剤、分
散剤、あるいはメタノール、エタノール、アセトン、ア
セトニトリル等の有機溶剤等と併用してもよい。When these (A) have a low solubility in an aqueous bleaching solution, they are used in combination with a solubilizer such as a surfactant, an emulsifier, a dispersant, or an organic solvent such as methanol, ethanol, acetone, acetonitrile or the like. You may.
【００１１】また、本発明の方法において（Ａ）ととも
にマグネシウム化合物等のアルカリ土類金属塩、キレー
ト剤等のセルロースの重合度の低下を防止する薬剤、ま
たは縮合リン酸塩、珪酸塩等の過酸化物漂白における安
定化剤等を併用してもよい。Further, in the method of the present invention, together with (A), an alkaline earth metal salt such as a magnesium compound, an agent for preventing a decrease in the degree of polymerization of cellulose such as a chelating agent, a condensed phosphate, a silicate or the like. You may use together a stabilizer etc. in oxide bleaching.
【００１２】本発明の漂白方法の対象となるセルロース
含有材料はＧＰ（砕木パルプ）、ＲＭＰ（リファイナー
メカニカルパルプ）、ＴＭＰ（サーモメカニカルパル
プ）、ＣＧＰ（ケミグラウンドパルプ）、ＳＣＰ（セミ
ケミカルパルプ）、ＳＰ（サルファイトパルプ）、ＫＰ
（クラフトパルプ）、ＡＰ（アルカリパルプ）、古紙パ
ルプ等であり木材（針葉樹、広葉樹）、非木材（草本
類）パルプいずれにも実施可能である。また、セルロー
ス含有材料のスラリー濃度は低濃度（１０重量％未
満）、中濃度（１０〜２０重量％）、高濃度（２０重量
％以上）のいずれにも適応可能である。The cellulose-containing material which is the object of the bleaching method of the present invention is GP (ground wood pulp), RMP (refiner mechanical pulp), TMP (thermomechanical pulp), CGP (chemiground pulp), SCP (semichemical pulp), SP (sulfite pulp), KP
(Craft pulp), AP (alkali pulp), waste paper pulp, etc., and can be applied to any of wood (coniferous and hardwood) and non-wood (herbaceous) pulp. The slurry concentration of the cellulose-containing material is applicable to any of low concentration (less than 10% by weight), medium concentration (10 to 20% by weight), and high concentration (20% by weight or more).
【００１３】本発明の漂白方法に使用されるアルカリ性
媒体は、水酸化ナトリウム、炭酸ナトリウム、炭酸水素
ナトリウム、アンモニア、クラフト法白液、酸化白液、
緑液、酸化緑液、四ホウ酸ナトリウム、メタホウ酸ナト
リウム等が使用できるが、通常水酸化ナトリウムを使用
する。絶乾パルプ重量当たりのアルカリ添加量はＮａ2
Ｏ換算で０．５〜３％が好ましい。The alkaline medium used in the bleaching method of the present invention is sodium hydroxide, sodium carbonate, sodium hydrogen carbonate, ammonia, Kraft white liquor, oxidized white liquor,
Green liquor, oxidized green liquor, sodium tetraborate, sodium metaborate and the like can be used, but sodium hydroxide is usually used. The amount of alkali added per weight of bone-dry pulp is Na 2
It is preferably 0.5 to 3% in terms of O.
【００１４】本発明の漂白方法に使用される酸素として
は、酸素および酸素富化空気のいずれもが使用可能であ
るが、反応容器の容積、および反応効率を考慮して酸素
ガスを使用するのが好ましい。また酸素の圧力は、高圧
（１０Kg/cm2G以上）から低圧（１０Kg/cm2G未満）まで
使用できるが本発明の効果を最大に発揮するには比較的
低圧（１〜５Kg/cm2G）で実施する方が好ましい。As oxygen used in the bleaching method of the present invention, both oxygen and oxygen-enriched air can be used, but oxygen gas is used in consideration of the volume of the reaction vessel and the reaction efficiency. Is preferred. The pressure of the oxygen pressure (10 Kg / cm 2 or more G) from to a low pressure (10 Kg / cm less than 2 G) can be used but relatively low pressure to exert the maximum effect of the present invention (1-5 kg / cm 2 It is preferable to carry out in step G).
【００１５】本発明の方法は、好適には酸素漂白工程で
実施されるが蒸解途中、蒸解後等のいずれの段階でも適
応可能である。The method of the present invention is preferably carried out in an oxygen bleaching step, but can be applied at any stage during or after cooking.
【００１６】本発明の漂白方法に使用される漂白装置
は、縦型、横型等の反応装置のいずれも使用可能であ
る。（Ａ）の添加方法はアップフロー方式の漂白塔の塔
底から、あるいはセルロース含有材料が酸素ガスおよび
／または過酸化物と混合される前、同時または後のいず
れの時期に添加してもよいが、攪拌効率の面から、混合
されると同時期か、混合される前が好ましい。また、通
常、温度は室温〜２００℃、反応時間は３０秒〜２０時
間で実施する。The bleaching apparatus used in the bleaching method of the present invention may be a vertical type, a horizontal type or the like. The addition method of (A) may be from the bottom of an upflow bleaching tower, or at any time before, simultaneously with or after the cellulose-containing material is mixed with oxygen gas and / or peroxide. However, from the viewpoint of stirring efficiency, it is preferable to be at the same time as before mixing or before mixing. The temperature is usually room temperature to 200 ° C., and the reaction time is 30 seconds to 20 hours.
【００１７】[0017]
【実施例】以下実施例により本発明を更に説明するが、
本発明はこれに限定されるものではない。実施例に用い
たパルプは広葉樹クラフトパルプ（カッパー価２０．
０、パルプ粘度２６．０）であり、表中の％は重量％を
示す。漂白度の一指標であるカッパー価および、セルロ
ース強度の一指標である粘度の測定法は下記のとおりで
ある。なお、カッパー価は小さいほど漂白度が高く、粘
度は高いほどセルロース強度が高い。 カッパー価測定法：パルプのカッパー価測定法（TAPPI
T236-m-60） 粘度測定法 ：銅エチレンジアミンを溶媒として用
いるパルプの粘度測定法（TAPPI T230-su-66）The present invention will be further described with reference to the following examples.
The present invention is not limited to this. The pulp used in the examples is a hardwood kraft pulp (Kappa number 20.
0, pulp viscosity 26.0), and% in the table indicates% by weight. The kappa number, which is an index of bleaching degree, and the viscosity, which is an index of cellulose strength, are measured as follows. The smaller the Kappa number, the higher the bleaching degree, and the higher the viscosity, the higher the cellulose strength. Kappa number measurement method: Pulp kappa number measurement method (TAPPI
T236-m-60) Viscosity measurement method: Pulp viscosity measurement method using copper ethylenediamine as solvent (TAPPI T230-su-66)
【００１８】実施例１〜４、比較例１〜２ 絶乾パルプに苛性ソーダ水溶液（苛性ソーダ量は、Ｎａ
2Ｏ換算で絶乾パルプ重量当り３％）および表１に示す
（Ａ）を添加し、室温下ニーダーにて１０分間混練し、
パルプスラリーを調製した。これをオートクレーブに入
れ、酸素ガスで充分置換した後、酸素圧３Kg/cm2G、温
度９０℃に保ち３０分反応させた。反応終了後、酸素圧
を解き、オートクレーブからパルプスラリーを取り出
し、蒸留水で十分洗浄し、ろ過後、乾燥させ漂白パルプ
を得た。得られたパルプのカッパー価と粘度を表１に示
す。Examples 1 to 4 and Comparative Examples 1 to 2 An absolutely dry caustic soda aqueous solution (the amount of caustic soda is Na
3% based on absolute dry pulp weight ( 2 O) and (A) shown in Table 1 were added and kneaded in a kneader at room temperature for 10 minutes,
A pulp slurry was prepared. This was placed in an autoclave and sufficiently replaced with oxygen gas, and then the reaction was carried out for 30 minutes while maintaining the oxygen pressure at 3 kg / cm 2 G and the temperature at 90 ° C. After completion of the reaction, the oxygen pressure was released, the pulp slurry was taken out from the autoclave, sufficiently washed with distilled water, filtered and dried to obtain a bleached pulp. Table 1 shows the Kappa number and viscosity of the obtained pulp.
【００１９】[0019]
【表１】 ＊１：テトラアセチルエチレンジアミン ＊２：絶乾パルプ重量当たりの添加量[Table 1] * 1: Tetraacetylethylenediamine * 2: Amount added per weight of bone-dry pulp
【００２０】[0020]
【発明の効果】本発明のパルプ漂白用助剤は次の様な効
果を奏する。 (1)パルプ濃度に関わらず、漂白の効果が大きい。 (2)温和な漂白条件で実施できる。 (3)製品の品質が安定する。 以上の効果を奏することから、本発明の漂白方法は生産
性を向上させ、工業上有用なものである。EFFECTS OF THE INVENTION The pulp bleaching aid of the present invention has the following effects. (1) The bleaching effect is great regardless of the pulp concentration. (2) It can be performed under mild bleaching conditions. (3) Product quality is stable. Because of the above effects, the bleaching method of the present invention improves productivity and is industrially useful.
Claims (2)
ーを、酸素ガスおよび／または過酸化物で処理する方法
において、アミンのアシル化物（Ａ）の存在下で処理す
ることを特徴とするセルロースパルプの漂白方法。1. A method for bleaching cellulose pulp, which comprises treating an alkaline water slurry of cellulose pulp with oxygen gas and / or peroxide, in the presence of an acylated product (A) of an amine. .
る請求項１記載の漂白方法。2. The bleaching method according to claim 1, wherein the (A) is an acetylated product of an amine.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1947392A JPH05186989A (en) | 1992-01-07 | 1992-01-07 | Method for bleaching cellulose pulp |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1947392A JPH05186989A (en) | 1992-01-07 | 1992-01-07 | Method for bleaching cellulose pulp |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05186989A true JPH05186989A (en) | 1993-07-27 |
Family
ID=12000302
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1947392A Pending JPH05186989A (en) | 1992-01-07 | 1992-01-07 | Method for bleaching cellulose pulp |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05186989A (en) |
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-
1992
- 1992-01-07 JP JP1947392A patent/JPH05186989A/en active Pending
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