木聚糖酶预处理对麦草化学机械浆可漂性及白度的改善

探讨了以玉米芯片为碳源制备木聚糖酶及麦草化学机械浆经该木聚糖酶预处理后可漂性和白度的改善效果。结果表明，直接以玉米芯为底物、里氏木霉为菌种产酶效果较好，当底物浓度为18g/L时，木聚糖酶活力可达38．34IU／mL。木聚糖酶预处理有利于改善麦草化机浆的可漂性，促进其过氧化氢漂白，有提高漂白浆白度，降低漂剂消耗。研究表明，当经单段H2O2漂至相同白度时，木聚糖酶预处理后可节约50％的H2O2用量。若麦草CMP酶处理后采用高浓度两段过氧化氢漂白，即XP3P3漂序（H2O2总量为6％0时，白度可达60％（ISO）以上。     

13C CP/MAS nuclear magnetic resonance study of the peroxide bleaching of ultra high yield chemimechanical pulp produced from sound and spruce budworm killed balsam fir

Summary The chemimechanical pulping (CMP) of sound balsam fir and the subsequent peroxide bleaching of the CMP pulp were investigated using solid state ¹³C CP/MAS NMR. A parallel study was made of a CMP pulp produced from spruce budworm killed balsam fir. Changes in the lignin and hemicellulose components were readily evident. The residual lignin and carbohydrate macromolecules in dead balsam fir CMP appeared to be the same as those in the sound wood CMP, before and after bleaching.We are indebted to Mr. S. S. Johal and Dr. J. V. Hatton of PAPRICAN, Vancouver, B.C., for generously supplying the wood and pulp samples. We also appreciate the assistance of Dr. N. R. Jagannathan with the ¹³C CP/MAS NMR measurements. Financial support from NSERC, in the form of a Postdoctoral Fellowship (JMW) and operating grants (FGH), is gratefully acknowledged     

TCF Bleaching of Populus tomentosa Kraft Pulps with H2O2 Pretreatment under Acid Condition

The process of peroxide bleaching of Populus tomentosa kraft pulp with H2O2 pretreatment under acid condition was studied. The variations of pulp characteristics such as brightness, Kappa number and viscosity during the peroxide bleaching process were discussed and the concept of the A/B value was presented for the first time. The results show that acid pretreatment with H2O2 is essential to improve pulp brightness and avoid viscosity loss. The conclusion is reached that the A/B value has great influence on pulp properties when the total amount of peroxide used in the bleaching process is 2%–5%. Pulp with a high viscosity and brightness can be obtained when A/B is about 0.15.     

甲脒亚磺酸用于麦草Soda-AQ浆漂白的研究

对甲脒亚磷酸（ＦＡＳ）用于麦草Ｓｏｄａ－ＡＱ浆漂白的可能性进行了研究，重点考察了麦草Ｓｏｄａ－ＡＱ浆过氧化氢（Ｐ）和甲脒亚磺酸（Ａ）两段漂白中的几个过程变量（Ｈ２Ｏ２和ＦＡＳ用量、温度、时间）对漂白的影响，找出了较佳的ＰＦ漂白工艺条件。结果表明，Ｐ段Ｈ２Ｑ用量２％～３％（对绝干浆）、Ｆ段ＦＡＳ用量０．５％（对绝干浆）、温度７０℃、时间３（）ｎｄ为较佳的漂白工艺条件。研究中发现，Ｌ＊与白度呈线性正相关。ａ＊与Ｌ＊呈线性负相关，而ｂ＊与Ｌ＊之间无明确的相关性。     

TCF bleaching of <Emphasis Type="Italic">Populus tomentosa</Emphasis> kraft pulps with H<Subscript>2</Subscript>O<Subscript>2</Subscript> pretreatment under acid condition

The process of peroxide bleaching of Populus tomentosa kraft pulp with H₂O₂ pretreatment under acid condition was studied. The variations of pulp characteristics such as brightness, Kappa number and viscosity during the peroxide bleaching process were discussed and the concept of the A/B value was presented for the first time. The results show that acid pretreatment with H₂O₂ is essential to improve pulp brightness and avoid viscosity loss. The conclusion is reached that the A/B value has great influence on pulp properties when the total amount of peroxide used in the bleaching process is 2%–5%. Pulp with a high viscosity and brightness can be obtained when A/B is about 0.15. [Supported by the National “863” Project (Grant No. 2002AA241071)]     

DMD的活化预处理及其全无氯漂序的研究

研究了桉木硫酸盐浆对氧脱木质素段和过氧化氢漂段的活化作用以及ＤＭＤ用量对氧段和过氧化氢段浆性能的影响,使经ＭＯＱＭＰ多段漂白的纸浆最终白度达８０％以上,纸浆粘度满足要求,可以实现桉木硫酸盐浆的全无氯漂白。     

Semipilot-scale bleaching of Kraft pulp with manganese peroxide

Crude Manganese Peroxidase (MnP) preparations from the fungus Bjerkandera sp. BOS55 were tested for their abilities to bleach and delignify oxygen delignified Eucalyptus Kraft pulp in a sequence combining a chelating and a peroxide stage. The inclusion of the enzymatic treatment in the bleaching sequence helped considerably to improve the final brightness. Other interesting results included moderate Kappa reduction, slight yield loss and paper sheets with an acceptable breaking length and burst index.     

甲脒亚磺酸漂白废旧新闻纸脱墨浆

采用甲脒亚磺酸(FAS)对废旧新闻纸脱墨浆进行了单段漂白实验,探讨了FAS用量、NaOH和FAS用量比、浆浓、漂白温度和时间对纸浆漂白的影响。结果表明:废旧新闻纸脱墨浆采用单段FAS漂白,其最佳工艺条件为FAS用量0.6%,NaOH用量0.3%,浆浓5%,温度70℃,时间60 min,纸浆白度可达57.9%SBD。     

麦草爆破制浆漂白性能研究(英文)

本文就麦草浆漂白的性能进行了探讨，以期改善纸浆白度．Ｈ２Ｏ２漂白剂因漂白损失小、漂后白度稳定性好，从而常用于纸浆漂白，特别是高得率浆的漂白．为寻找Ｈ２Ｏ２的漂白规律，本文对Ｈ２Ｏ２漂白过程的影响因素进行了研究．漂白剂Ｈ２Ｏ２在水中电离生成ＯＯＨ－作为漂白的有效成分，其浓度的提高使反应顺利进行．因此增加Ｈ２Ｏ２用量将获得较好的漂白效果．Ｈ２Ｏ２在碱ｐＨ缓冲剂存在的环境中电离，将产生一个较稳定的ＯＯＨ－浓度，使漂白反应稳定．但是过高的ｐＨ值会导致Ｈ２Ｏ２分解，同时碱与浆中木素的反应生成新的发色基因，使纸浆白度下降．适当的温度会促使Ｈ２Ｏ２的电离，使漂白反应顺利进行．但温度过高则使Ｈ２Ｏ２分解，失去漂白作用．为消除重金属离子对Ｈ２Ｏ２的催化分解作用，加入了螯合剂．根据ＭｏｎｉｃａＬｕｎｄｑｕｉｓｔ的研究模型，本文对麦草爆破浆的Ｈ２Ｏ２漂白进行了研究，白度值可表示为ｄＷｄｔ＝ｋ［Ｈ２Ｏ２］０．２３４０［ＮａＯＨ］１．２６１９Ｗ－１．８１７６．公式表明：较高的Ｈ２Ｏ２浓度、ＮａＯＨ浓度及较少的发色因素对白度提高有利．从公式中还可看出在保证必需的Ｈ２Ｏ２用量的情况下，ｐＨ值的控制对白度的提高是一个关键因素．由于漂白反应     

马尾松硫酸盐浆过氧化氢强化氧漂的研究

探讨了预处理和过氧化氢强化氧漂对氧漂浆性能的影响,结果表明：采用酶、螯合预处理能较多地提高氧漂的选择性和脱木素程度,而对漂后浆的白度影响较小。在氧漂过程中添加过氧化氢能大幅度提高预处理浆的白度,而浆的卡伯值和粘度下降较小。     

On the selectivity of ozone delignification of softwood kraft pulps

Summary Ozonation of kraft pulp and oxygen-delignified kraft pulp in acetic acid/water mixtures has been studied at different pulp consistencies with and without an inhibitor to obtain information about the limitations of the selectivity of the ozone treatment. The experiments have been performed according to a full factorial design and data have been analysed by stepwise regression analysis. The results show that a better delignification selectivity can be achieved when ozone is applied in acetic acid media instead of conventional aqueous media. By combining conventional oxygen delignification and ozonation in acetic acid, pulps with equal strength properties and better optical properties compared to those of conventional O(DC)E prebleached pulps can be obtained. This study has also revealed that the reagent is utilized far more efficiently in ozonation at high pulp consistency (35%) than in ozonation at low consistency (1%), and that a similar selectivity can be achieved in both types of ozonation by choosing appropriate conditions. The greater selectivity of ozonation in acetic acid than in water is interpreted in terms of different stabilities of the oxidant in these reaction media. The relation between the formation of hydroxyl radicals and the extent and selectivity of delignification during ozonation has been investigated. The final bleaching of pulps prebleached with ozone in acetic acid medium has been studied. Two final bleaching sequences are presented, by which pulps with ISO brightness levels of 79% and 90% can be produced.The authors are indebted to the Swedish National Board for Technical Development (Styrelsen för Teknisk Utveckling) for financial support for this work and to STORA Technology for pulp tests and analyses     

Performance of new and commercial xylanases for ECF and TCF bleaching of eucalyptus kraft pulp

Since xylanases can differ widely in their bleaching efficiency, the performance of one new and two commercial xylanases was evaluated in an eucalyptus kraft pulp following XD (X: xylanase; D: chlorine dioxide) and XP (P: hydrogen peroxide) sequences. The new xylanase did not show a significant bleach boosting effect but increased the hexenuronic acid (HexA) removal by 10% after the D stage. The two commercial xylanases behaved in a different way, being one of them (X_C) the most effective in increasing delignification (9%) and brightness (3%ISO). Its effectiveness was related to its greater action on releasing the xylan polymer, thus producing also a strong decrease in the HexA contents during the enzymatic stage (15%). All xylanases produced morphological changes in the fibre surfaces, but only with X_C cracks and holes that improved the diffusion of reactives were observed. Finally, the best bleaching results were obtained with the XD sequence and therefore, a complete bleaching sequence XDEopD₁ (Eop: alkaline extraction with oxygen and peroxide) was carried out with the best enzyme.     

麦草氧碱蒸煮浆的低温压力过氧化氢漂白

对麦草在低温(85℃)下氧碱蒸煮,所得草浆在较低温度(80℃)下进行压力过氧化氢漂白。漂白后浆料卡伯值从17.9降至9.4～11.9;黏度比漂白前浆料黏度稍有增加,从1 042 mL/g增加到1 158～1 192 mL/g;纸浆白度(ISO)从37.1%升高至45.6%～60.6%,且与卡伯值之间具有一定的线性关系:白度增加=卡伯值降低×1.57;浆料得率在86.6%～89.5%之间,同时得率降低与卡伯值减少之间具有较为标准的线性关系:浆料得率降低=卡伯值降低×0.19。     

桉树制浆综述

本文介绍了(1)用桉木生产漂白化学浆,包括硫酸盐法和碱一蒽醌法制浆;(2)用按木生产漂白半化学浆,主要是中性亚硫酸盐半化学高得率浆;(3)用桉木生产漂白化学机械浆,包括冷碱法和亚硫酸盐法制浆;(4)用桉木生产漂白化学热磨机械浆。     

Industrial utilization of tobacco stalks II: preparation and characterization of tobacco pulp by steam explosion pulping

Our previous paper showed tobacco stalks to posses the characteristics of a raw material for pulp and paper application. It contains the major biomass constituents and cell components common to wood species. In this study, preparation and characterization of tobacco stalk pulp by steam explosion (SE) pulping at two chemical pretreatments were attempted. Chemical pretreatment prior to SE pulping improved the brightness, yield, and strength properties of the resulting tobacco SE pulps in the order: 6% Na₂SO₃ + 1% NaOH > 6% Na₂SO₃ > control (untreated). The 6% Na₂SO₃ + 1% NaOH-impregnated tobacco stalks produced SE pulps of good fiber length distribution and considerable properties that compare well with pulps from other raw materials obtained from previous studies, and the nonimpregnated ones showed strength properties superior to those of their poplar counterpart. Prior to bleaching, pretreating the tobacco stalk SE pulps with two stages, 2% NaOH at 90°C, improved the initial pulp brightness by about 5 points. Two-stage 6% H₂O₂ bleaching gave a comparable effect with hypochlorite bleaching for both tobacco and poplar, giving a 29–34 brightness point increase for tobacco SE pulp and 61 for the poplar samples. The differences in the bleaching responses for untreated tobacco and poplar SE pulps were attributed to the differences in their lignin structure, as shown in the total yield of their respective nitrobenzene oxidation products and FT-IR spectra. Tobacco SE pulps contain more of the guaiacyl-type lignin and poplar the syringyl-type lignin.This paper was presented in part during the 1998 CORESTA (Cooperation Centre for Scientific Research Relative to Tobacco) Congress, Brighton, UK, October 1998     

硫酸盐竹浆氧脱木质素和全无氯漂白的研究

通过比较不同条件下氧脱木质素后浆料的卡伯值、黏度、得率、白度和脱木质素选择性等指标,研究了硫酸盐竹浆卡伯值25.6氧脱木质素工艺参数,发现用碱量和温度是决定氧脱木质素效果的主要因素.最佳工艺条件为:用碱量3.5%,温度85℃,氧气压力0.6MPa,保温时间80min.两段氧脱木质素(中间不洗涤)可以提高木质素脱除率和选择性.研究还发现,在氧碱脱木质素过程中加入醌类混合物助剂(表示为Oq),可使浆料的黏度和氧脱木质素的选择性大大提高.采用OQ(PO)、(O1O2)Q(PO)、OQ(PO)1(PO)2和OqQ(PO) 4种短漂序都可使竹浆白度达到80%(ISO) 以上,且具有很好的白度稳定性.OQ(PO)、(O1O2)Q(PO)和OQ(PO)1(PO)2 3种漂序漂后浆纸页强度性能相近,OqQ(PO)漂后浆的抗张指数、撕裂指数和耐破指数明显高于其它3种漂序.     

Biobleaching of unbleached and oxygen-bleached hardwood kraft pulp by culture filtrate containing manganese peroxidase and lignin peroxidase fromPhanerochaete chrysosporium

Unbleached and oxygen-bleached hardwood kraft pulp (UKP and OKP), respectively, were bleached with a culture filtrate containing manganese peroxidase (MnP) and lignin peroxidase (LiP) fromPhanerochaete chrysosporium Burds. The brightness increases of UKP upon biobleaching with the culture filtrate with and without MnSO₄ were the same. The brightness increase of OKP with MnSO₄ decreased to about half that seen without MnSO₄. Changes in the brightness of UKP and OKP by treatment with the culture filtrate were determined. The brightness increased sharply by about eight points during the first 3h. The 3-h treatment was repeated seven times. The brightness increased linearly with the bleaching of UKP. On bleaching of OKP, the brightness increased slowly and stopped at about 78%.Part of this report was presented at the 62nd Pulp and Paper Research Conference of the Japan Tappi, Tokyo, June 1995     

新型绿色糖单孢菌复合胞外酶对比纯木聚糖酶助漂杨木KP浆研究

用绿色糖单孢菌复合胞外酶和纯木聚糖酶分别对三倍体毛白杨KP浆进行单段酶预处理及后续ECF、TCF漂白,结果发现,绿色糖单孢菌复合胞外酶助漂效果明显,接后续漂白可制得白度均高于85%ISO,粘度保持在1000mL/g左右的高白度、高强度、低氯和无氯全漂浆.相对传统纯木聚糖酶助漂,复合胞外酶在提高纸浆白度方面表现更佳,在保持纸浆粘度方面效果稍差.此外,三倍体毛白杨制浆漂白性能良好,ECF碱抽提段加入0.5%的H2O2可强化碱抽提效果,氧脱木素作用明显,是TCF漂白必不可少的组成部分.     

Response of <Emphasis Type="Italic">Eucalyptus camaldulensis</Emphasis> and <Emphasis Type="Italic">Acacia mangium</Emphasis> kraft pulp in different ECF bleaching options

In this study, the response of Eucalyptus camaldulensis and Acacia mangium kraft pulp to different options of ECF bleaching was investigated. Oxygen-delignified pulps of both species having similar kappa number (c.a. 12) were used. Both the pulps were prebleached using conventional ClO₂ stage (D₀), combined use of ClO₂ and O₃ (DZ), hot acid treatment before D₀ (A_hotD₀) and hot acid treatment before (DZ) i.e., A_hot(DZ), hot ClO₂ treatment (D_HT) and A_hot followed by D_HT (A_hotD_HT). All prebleached pulps were finally bleached to 90%+ ISO brightness using D₁ option. The overall benefits of other options were not considerable compared to D₀ and (DZ). From the ClO₂ consumption point of view, for a certain species, the option A_hot(DZ) was the best. Instead of D₁ in final bleaching, pressurized hydrogen peroxide (PO) was also investigated in the case of D₀ and (DZ) prebleached pulps. (PO)-bleached pulp produced higher brightness stability but lower viscosity compared to D₁.     

杨木制浆技术的新进展

本文介绍了用杨木生产漂白化学浆,包括硫酸盐法,硫酸盐-蒽醌法,烧碱-蒽醌法和碱性亚硫酸钠-蒽醌法制浆;用杨木生产漂白化学热磨机械浆;用杨木生产碱性过氧化氢机械浆;特别是杨木碱性过氧化氢机械浆是90年代发展研制成功的高得率、高白度和强度性好的新化学机械浆种,它适用于配抄低定量胶印新闻纸、低定量涂布纸等。