ONP脱墨浆二氧化硫脲漂白研究

实验主要探讨了ONP脱墨浆FAS单段漂白的工艺条件,找出了FAS漂白的最佳工艺条件为:FAS用量0.6%,NaOH用量0.3%,漂白温度65℃,漂白时间30min,浆浓10%,在此条件下漂后浆白度达66.6%ISO。     

微波辐射应用于麦草浆漂白工艺的研究

将微波辐射代替传统水浴加热应用于H2O2麦草浆漂白工艺中。研究了微波辐射时间、辐射功率、H2O2用量和NaOH用量等因素对纸浆漂白效果的影响。通过与传统水浴加热漂白对比发现,达到相应白度时微波辐射漂白时间大大缩短;微波辐射漂白纸浆粘度没有过多下降;微波辐射漂白废水中的残余过氧化物只有水浴漂白的10%。正交实验结果表明H2O2用量的影响最大,其次是微波辐射时间和NaOH用量,影响最小的是微波输出功率。最佳实验条件为微波辐射功率240?W、辐射时间25?min、H2O2用量5％和NaOH用量4％时纸浆白度约为59％ISO,纸浆粘度大于620?mL·g-1,纸浆硬度约为390。     

云南松-蓝桉混合浆漂白的研究

改进的硫酸盐蒸煮浆比常规硫酸盐浆有较好的漂白性，在相同的漂白工艺条件下，改进的硫酸盐蒸煮浆比常规硫酸盐浆所用的化学药品少而成浆白度高。用改良硫酸盐法制得的浆比常规硫酸盐法制得的浆易漂；用氧碱次氯酸钠漂白，蓝桉比例大的成浆白度高，比例少的白度较差，且氧碱次氯酸钠漂白比常规次氯酸钠漂白成浆白度可提高2～3倍；过氧化物H2O2的漂白过程聚合度下降较少，很适合强煮弱漂的制浆工艺，成浆白度与次氯酸钠相差不大，但可减少污染。用蓝桉60％的混合材制的浆粕，进行纺丝验证试验，纺丝的各种性能好，能纺出质量较好的粘胶纤维。     

硫酸盐木浆漂白前木聚糖酶预处理的研究

研究了木聚糖酶用于硫酸盐木浆 H2 O2 漂白前预处理的工艺条件 ,结果表明 ,预处理最佳工艺条件为 :酶用量为每克浆 2 0 IU ,时间 3h,浆浓为 6 %。在相同的 H2 O2 漂白条件下 ,经酶处理后的浆料白度可提高 2 %～ 3% SBD。     

改良木聚糖酶辅助漂白芦苇浆的工艺研究

采用分子改良后的木聚糖酶对芦苇浆进行生物预处理,考察了改良木聚糖酶辅助漂白的效果。结果表明,酶预处理可以降低CEH三段漂白中氯化C段的氯气用量60%。改良木聚糖酶预处理辅助漂白芦苇纸浆最佳条件为:pH为7.0,温度60℃,浆浓(质量分数)5%,酶用量12μmol/(min.g),预处理时间60 min。在此条件下C段氯用量降至对照的40%时,酶处理漂后样品白度可达到84.0%(ISO),高出对照样的白度3.7%(ISO)。改良木聚糖酶预处理还能够改善纸浆漂后样的物理性能。     

桉树制浆造纸性能的研究(第二报)——雷州半岛四种桉树浆的漂白试验

<正>对柠檬桉烧碱—蒽醌浆(AP+AQ)和硫酸盐浆(KP)进行了H单段,H—H两段,C—E—H三段以及C—E—H—D四段漂白试验。对雷林一号桉、草律桉、窿缘桉硫酸盐浆还做了H单段漂白性能的对比试验。结果表明:在用氯量7％、浆浓6％,温度40℃、时间3小时的H单段漂白条件下,柠檬桉(AP+AQ)和柠檬桉(KP)的白度均可达70度以上。采用C—E—H—D四段漂,用氯量为6％,柠檬桉(AP+AQ)的白度超过80度,D.P.在800以上。四种桉树中,雷林一号桉的漂白性能最好,窿缘桉最难漂白,草律桉与柠檬桉的漂白性能相近。柠檬桉、草律桉、雷林一号桉制得的漂白浆,物理强度甚好,裂断长6060—8050米,耐折度59—413次,可以用来生产一般文化用纸,也可考虑用来生产某些高级纸张。     

家具用北美鹅掌楸漂白工艺优化

为了提高家具用北美鹅掌楸木材的利用率,充分发挥变色木材的价值,以H2O2为漂白主剂对试材进行漂白正交试验,以得到最佳漂白工艺参数。以各组成药剂质量分数和漂白工艺作为试验因素,以漂白后试材的色差和白度为主要评价指标,综合极差分析和方差分析结果,并综合考虑实际生产情况,得到家具用北美鹅掌楸木材的较佳漂白工艺为:H2O2质量分数6%,漂液pH 9.5~10.0,Na2SiO3质量分数0.4%,温度70℃,漂白处理时间60~90min。在此漂白工艺条件下,可有效去除试材的材色不均,使整体材色变浅,色差值为21.27 NBS,白度值为62.12%。     

越南甜竹制浆漂白性能的研究

以越南甜竹为研究对象,经KP法蒸煮后,进行 DEpQP漂白,系统分析了其制浆漂白性能。KP法蒸煮适宜工艺条件为:碱(NaOH计)、硫、AQ质量分数分别为22%、20%、0.1%,液比为1∶4,最高温度为170℃,保温时间120min. 蒸煮结果为:粗浆得率381%, Kappa值1847,白度2525%(ISO)。采用单因素法研究DEpQP漂白中D段ClO2、Ep段H2O2、P段H2O2的最佳用量,漂白结果为:卡伯值114,白度 7932%(ISO),黏度9314mL/g.     

家具用北美鹅掌楸漂白工艺优化

为了提高家具用北美鹅掌楸木材的利用率,充分发挥变色木材的价值,以H2O2为漂白主剂对试材进行漂白正交试验,以得到最佳漂白工艺参数。以各组成药剂质量分数和漂白工艺作为试验因素,以漂白后试材的色差和白度为主要评价指标,综合极差分析和方差分析结果,并综合考虑实际生产情况,得到家具用北美鹅掌楸木材的较佳漂白工艺为:H2O2质量分数6%,漂液pH 9.5~10.0,Na2SiO3质量分数0.4%,温度70℃,漂白处理时间60~90min。在此漂白工艺条件下,可有效去除试材的材色不均,使整体材色变浅,色差值为21.27 NBS,白度值为62.12%。     

蔗渣氧脱浆二氧化氯漂白工艺参数的优化

采用三因素二次通用旋转组合实验设计,对蔗渣氧脱浆二氧化氯漂白的主要工艺参数(ClO2用量、NaOH用量和漂白时间)进行了优化,建立了工艺参数与纸浆卡伯值、白度及可吸附有机卤化物(AOX)产生量之间的二次多项式非线性回归数学模型.结果表明:通过实验设计建立的数学模型回归显著,失拟不明显;3个工艺参数对纸浆卡伯值、白度及AOX产生量的影响由大到小的顺序均依次为ClO2用量、漂白时间、NaOH用量;在优化模拟得到的较佳工艺条件(ClO2用量0.79%,NaOH用量0.43%,漂白时间53 min)下,纸浆卡伯值为1.83,白度为73.3%ISO,废水中AOX质量浓度为10.8 mg/L,与验证实验得到的纸浆卡伯值(1.76)、白度(75.0%ISO)和废水中AOX质量浓度(11.3mg/L)接近.     

竹子化机浆漂白工艺及其机理

 竹子作为一种重要的非木材制浆造纸资源,具有生长周期短、储量大及成本低等优点,但是其成浆存在白度低、白度稳定性差、易返黄、废液硅含量高难处理等问题。本研究利用H₂O₂、NaBH₄、Na₂S₂O₄和CH₃COOOH等漂白剂对粉单竹碱性过氧化氢化学机械浆（APMP）进行单段或者两段组合补充漂白,以提高竹子APMP浆的可漂性、白度及其稳定性、强度等。研究结果表明,常规H₂O₂漂白是竹子化机浆最佳单段补充漂白方法。两段补充漂白实验表明,白度提高最大的是H₂O₂→Na₂S₂O₄组合,为73.85% ISO;黏度下降最大的是H₂O₂→NaBH₄组合,漂后浆黏度从960下降到601 mL·g^-1。虽然两段补充漂白漂后浆的黏度有所下降,但其物理强度得到提高。补充漂白的示差红外分析发现：H₂O₂、H₂O₂→Na₂S₂O₄、H₂O₂→NaBH₄ 3种漂白方法的纸浆中共轭羰基含量降低了,而H₂O₂→CH₃COOOH漂白浆中的共轭羰基含量反而增加。甲氧基、紫丁香型木素和缩合的愈创木基环在H₂O₂→Na₂S₂O₄两段补充漂白过程脱除效果最显著。X射线衍射分析表明,补充漂白过程单段H₂O₂和H₂O₂→Na₂S₂O₄两段漂白对碳水化合物的降解作用最小。     

STUDY ON THE ELEMENTAL CHLORINE FREE BLEACHING OF BAMBOO KRAFT PULP

1INTRODUCTIONChina is a country using the most variety of non-wood fiber raw material and is the largest country producing non-wood fiber pulp and paper in the world[1]. Bamboo is one kind of the main non-wood species for papermaking in China. Although the structure of raw materials for papermaking has being adjusted through increasing the proportion of wood pulp and by effectively utilizing waste paper source, non-wood species will still remain an important fiber resource[1,2].At present…     

HE EFFECT OF TRANSITION METAL IONS-IRON ON HYDROGEN PEROXIDE BLEACHING

Hydrogen peroxide bleaching has been extensively used in high-yield pulp bleaching. Unfortunately,hydrogen peroxide can be decomposed under alkaline condition, especially when transition metal ions exit. Experiments show that the valence of transition metal ion is also responsible for the decomposition of hydrogen peroxide.Iron ions are present in two oxidation states, Fe2+ and Fe3+. They are both catalytically active to hydrogen peroxide decomposition. Because Fe3+ is brown, it can affect the brightness of pulp directly, it can also combine with phenol, forming complexes which not only are stable structures and are difficult to be removed from pulp, but also significantly affect the brightness of pulp because of their color.Sodium silicate and magnesium sulfate, when used together, can greatly decrease hydrogen peroxide decomposition. The optimum dosage of sodium silicate is about 0.1% (on solution) for Fe2+ and 0.25% (on solution) for Fe3+. Adding chelants such as DTPA or EDTA with stabilizers simultaneously can obviously improve pulp brightness. For iron ions, the chelate effect of DTPA is better than that of EDTA.Under acidic conditions, sodium hyposulfite and cellulose can reduce Fe3+ to Fe2+ effectively, and pulp brightness is improved greatly. Adding sodium thiosulfate simultaneously with magnesium sulfate,sodium silicate, and DTPA to alkaline peroxide solution can result in higher brightness of pulp.pH is a key parameter during hydrogen peroxide bleaching, the optimum pH value should be 10.5-12.     

THE EFFECT OF TRANSITION METAL IONS-IRON ON HYDROGEN PEROXIDE BLEACHING

INTRODUCTIONHydrogen peroxide bleaching has been extensively used in high-yield pulp bleaching. IT is well known that hydrogen peroxide can be easily decomposed under alkaline conditions, especially in the presence of transition metal ions due to their catalyzing effect on the decomposition of hydrogen peroxide. Some recent reports show that the valence of transition metal ion can have a drastic effect on the decomposition of hydrogen peroxide.Generally, iron can exist in Fe2+ and Fe3+…     

MODIFIED OPAL:A NOVEL STABILIZER FOR HYDROGEN PEROXIDE BLEACHING OF PULPS

The possibility of modified opal as the stabilizer of hydrogen peroxide bleaching was investigated. The results showed that the modified opal in place of sodium silicate as the stabilizer of hydrogen peroxide bleaching is feasible. At the same dosage, above 3% ISO can be increased for both wheat straw pulp and deinked pulp. The stabilizing ability of the modified opal to hydrogen peroxide bleaching of pulp is improved markedly. It is favorable for bleaching to increase temperature and time within a permissive extent. The suitable process conditions are 10% of pulp consistency, 3% of hydrogen peroxide, 1.5% of sodium hydroxide, 3% of the modified opal, 70℃ and 60 min when the modified opal is used as the stabilizer of hydrogen peroxide bleaching. At these conditions, the brightness gain can reach about 16% ISO for wheat straw pulp. In addition, it is favorable for bleaching to add a little magnesium sulfate when the modified opal is used as the stabilizer of hydrogen peroxide bleaching, the brightness of pulp can increase I%ISO if0.05% of magnesium sulfate is added. The cost analysis indicated that the modified opal is superior to sodium silicate as the stabilizer of hydrogen peroxide bleaching in economical aspect and has further the potential of market development.     

蔗渣浆的全无氯漂白工艺

对蔗渣浆采用过氧化氢强化的氧脱木素(OP)-螯合预处理(Q)-压力过氧化氢漂白(PO)的短序漂白,探讨了将蔗渣浆漂至82%ISO和用非硅过氧化氢漂白稳定剂代替硅酸钠用于过氧化氢漂白的可行性.研究表明,非硅过氧化氢稳定剂PP-1与PP-2耐高温、耐高压,可用于压力过氧化氢漂白.OP段氢氧化钠用量为2.0%(相对于绝干浆质量,下同)、过氧化氢用量为0.5%,PO段过氧化氢用量为3.0%、PP-1用量为0.1%、PP-2用量为0.5%时,蔗渣浆采用OPQPO流程漂白后,浆的白度可达到85%ISO.而且OPQPO从根本上消除了可吸附有机卤化物的产生;经测定,漂白废水属于可生物降解废水.     

毛竹碱性亚硫酸钠-蒽醌制浆的研究

<正>试验结果表明:亚硫酸钠对总碱(均以氧化钠计)最佳比率为0.85,总碱量为18％(以氧化钠计),蒽醌用量0.05％,液比为1:4,在最高温度(170℃)制浆时间需要3.5h,粗浆得率42～45％(比传统的硫酸盐法纸浆得率高4～6％)和卡伯值17～25,碱性亚硫酸钠-蒽醌制得竹浆的物理强度性质相当于硫酸盐竹浆的强度。     

低龄厚荚相思木的制浆造纸性能

对3年和6年生厚英相思,在各自的最佳硫酸盐法蒸煮工艺条件下,制取相近硬度的浆料,比较蒸煮、打浆、强度及漂白性能,进而对其制浆性能进行综合评价。     

微波法制备氰乙基化竹粉及其产物的表征

超声活化后的竹粉在微波辐射的作用下与丙烯腈反应制备氰乙基化竹粉,考察最佳用量和反应条件对氰乙基化反应的影响,并用电子显微镜、X-射线衍射分析(XRD)、红外(FTIR)和示差扫描量热分析(DSC)等对竹粉改性前后的微观结构和热塑性进行了初步研究.结果表明,1.5g竹粉在饱和KSCN的NaOH溶液的润胀作用下,超声活化10min后,与8mL丙烯腈微波辐射30min即可获得传统40℃水浴反应3h才能得到的增重率约为40%的氰乙基化竹粉.微波作用使竹粉的氰乙基化反应可以在非常温和的条件下(40℃)短时间内完成,减少了丙烯腈的水解和均聚等副反应.氰乙基化竹粉中竹纤维表面结构变得粗糙,管束结构消失,结晶度降低,并在145～290℃之间出现一个大的吸热峰.