全秆红麻磺化化学机械浆H2O2单段漂白

研究了全秆红麻磺化化学机械浆(SCMP)H_2O_2漂白过程中的各种影响因素,确定了H_3O_2漂白红麻 SCMP 的最佳工艺条件,在最佳条件下,H_2O_2将白度为54.9%的红麻未漂浆漂至71%以上白度;红外光谱表明,H_2O_2能够除去红麻 SCMP 中部分共轭羰基、β-羰基和羧基结构,从而达到漂白的目的。     

利用双氧水对大豆油进行脱色的实验报告

通过实验探索利用双氧水对大豆油进行脱色的工艺操作方法。经对脱色后油脂的各项理化指标及在贮藏过程中的变化情况进行测定表明,用双氧水对大豆油进行脱色是可行的。     

基于西门子S7-400的造纸漂白工段PLC控制系统

介绍了漂白工段在制浆造纸工业中的重要性,针对漂白工段复杂的工艺特性,给出了基于西门子S7-400控制系统的结构及硬件配置.同时采用多模态控制算法实现对塔温的优化控制.     

硫酸盐竹浆高温高压H2O2漂白工艺的研究

通过实验研究了硫酸盐竹浆高温高压过氧化氢漂白工艺．实验结果表明：高温高压过氧化氢漂白在加入4％（质量分数，下同）的H2O2，H2O2／NaOH用量比为1.3，MgSO4用量为0．5％，Na：SiO3用量为3％，控制反应温度为120℃，保温时间为60min，氧压为1．2MPa，浆浓为10％的条件下，漂后浆料白度达79．5％ISO，卡伯值达2．5，粘度为719mL／g．     

微电解深度处理造纸中段废水的研究

用微电解法对造纸中段废水二级生化处理后出水进行深度处理研究。结果表明：在pH为3、铁炭比（体积比）为2、H202投量为0．5Qth的最优条件下，中段废水的脱色率可达98％以上，CODcr去除率可达78％，微电解是一种经济有效的深度处理方法。     

Thermoluminescence characteristics of Sm<Superscript>3+</Superscript> doped NaYF<Subscript>4</Subscript> crystals

Thermoluminescence (TL) characteristics of NaYF₄ crystals doped with Sm³⁺ have been studied after γ-ray irradiation. Dependence of luminescence efficiency on Sm³⁺ concentration and radiation dose has been measured and possible applications of NaYF₄: Sm³⁺ as a novel phosphor for TL dosimetry have been investigated. The efficiency of 0·3 mole% Sm³⁺ doped NaYF₄ crystal has been found to be maximum and comparable with commercial thermoluminescence dosimetric (TLD) materials.     

再生白土对大豆油脱色效果的研究

用再生白土对大豆油进行脱色,并用新白土进行对比。通过实验确定再生白土的最佳脱色温度110℃,时间20m in,在此条件下再生白土的脱色率为97.66%,脱色效果与新白土相当。     

Comparison of Dye Behavior from Aspen HYP: Dyes Added in the HYP Manufacturing Process Versus Dyes Added at the Papermaking Wet End

Abstract

The yellowish color of High Yield Pulp (HYP) gives some psychological obstacles and limits its application in some paper grades. Dyes are widely used in the papermaking process to shade the yellowish color of the paper products. We proposed to add dyes into the HYP manufacturing process to minimize the yellowish hue. In this work, we substituted the dye-added HYP (dyes added in the HYP manufacturing process) for hardwood kraft pulp in the production of fine paper grades, and compared the results from those by adding dyes into the papermaking wet end. A higher dye effectiveness was obtained when we used the dye-added HYP. Also, the dye-added HYP gave more effective performance of Precipitated Calcium Carbonate (PCC) fillers and Optical Brightening Agents (OBA) in terms of CIE whiteness and b*. In addition, the dye-added HYP showed less negative effect on brightness and better compatibility with other dyes. The underlying mechanism for the above experimental observation was proposed.     

中温低碱短流程练漂新工艺研究

本研究以氧化退浆剂应用为基础。进行中温低碱短流程练漂新工艺研究，突破了传统的重煮轻漂工艺的格局，为实现环保练漂作了有益的尝试。     

The final bleaching of eucalypt kraft pulps with hydrogen peroxide: relationship with industrial ECF bleaching history and cellulose degradation

BACKGROUND: The process of chemical pulp bleaching is based for the most part in chlorine dioxide within elemental chlorine free (ECF) technologies. The use of greener alternatives such as bleaching with hydrogen peroxide (P stage) is not widely used owing to selectivity concerns related to transition metal‐catalyzed decomposition reactions. Even at the final stage where peroxide is recognized to boost brightness and improve the brightness stability of the bleached pulp, cellulose degradation often overcomes these advantages. This paper presents the results of studies intended to optimize final peroxide bleaching performance considering two standard ECF industrial bleaching sequences: the conventional DED and the ECF‐light OQ(PO)D (stages name: D—chlorine dioxide; E—alkaline extraction; O—oxygen; Q—chelation, (PO)—hydrogen peroxide pressurized with oxygen). RESULTS: The addition of sodium diethylenetriaminepentaacetate (DTPA) was the most effective option in terms of DED pulp bleachability and selectivity with hydrogen peroxide, as well as in terms of brightness reversion. As regards the OQ(PO)D pulp, a blend of DTPA and magnesium was the most beneficial in those properties. CONCLUSIONS: The choice of the best hydrogen peroxide stabilizer, among the different tested combinations of magnesium and chelants (EDTA and DTPA) studied, in terms of pulp bleachability, bleaching selectivity and brightness reversion is dependent on the impact of the previous bleaching stages on metallic nature and content. The pulp Mg/(Fe + Cu) ratio was highlighted as a process parameter controlling cellulose degradation in peroxide bleaching. Copyright © 2010 Society of Chemical Industry