过氧酸和DMD的性能及其在纸浆漂白中的应用

过氧酸和二氧环丙酮是类强的亲电氧化试剂 ,在反应中可有效转移氧原子。文章综述了这类氧化剂的性能及在纸浆漂白中的作用 ,作为可替代传统氯气漂白的最有希望的无污染漂剂 ,采用过氧酸和二氧环丙酮可实现纸浆的全无氯漂白     

洗衣房专用氧漂剂和氯漂剂的研制

介绍了洗衣房专用氧漂剂和氯漂剂的性能特点、配方设计、试验过程及最终配方确定等问题,洗衣房专用氧漂剂和氯漂剂的各项指标达到了新产品的开发目标。     

有机过氧酸的合成和利用

前言有机过氧酸分过氧羧酸R(CO_3H)_n和过磺酸RSO_2—OOH二种,R为烷基、环烷基和烯丙基等,n=1、2 有机过氧酸有过氧化物和酸的性质,是一种较强的氧化剂,但它的酸性比其母体酸弱。同H_2O_2相比,有机过氧酸的最大特点在于它能和许多有机化合物相溶,有利于有机反应的进行。低级脂肪族过氧酸是无色液体,有不愉快的刺激味,随分子量增加气味减小.高级过氧酸在室温时为固体。过氧酸的水溶性比其母体羧酸要好,长链脂肪族过氧酸不溶于水,但     

宾馆用氯漂与氧漂洗涤剂的性能及应用比较

本文介绍了宾馆用氯漂与氧漂的漂白机理，比较了氯漂与氧漂的性能、工艺条件和应用范围，论述了氯漂与氧漂的发展前景。     

黑化院建成生态氧无氯漂白剂实验装置

黑龙江省化工院日前建成世界上第一套千吨级生态氧新型环保无氯漂白剂工业化实验装置。该装置生产的过氧化硼酸钾可替代含氯漂白剂应用于纺织、印染、造纸和游泳池消毒领域。该成果打破了行业内公认的氧漂剂不能有效去除木质素的行业规律,不仅减少了废水排放,而且产品质量完全达到和超过传统氯漂工艺水平。     

过氧酸脱木素和漂白研究近况

本文综述了过氧酸的制备技术以及在纸浆脱木素和漂白中的研究近况。用作含氧漂白剂的过氧酸具有较强的木素活化作用，有希望取代ClO_2（D）而实现纸浆的TCF漂白。     

聚木糖酶对桉木KP预处理的影响

研究了聚木糖酶预处理的影响因素。添加表面活性剂可加强聚木糖酶的作用。聚木糖酶预处理可加强发包基团的去除，加强本素酚型结构与漂剂反应，提高次氯酸盐漂白浆白度，减少氯耗。     

炫丽调理剂BLF-3的基本性能及其在洗衣液中的应用研究

介绍了炫丽调理剂BLF-3的基本性能及其在洗衣液中的应用研究,并与市面上几种洗涤用荧光增白剂性能进行了比较。结果表明,与洗涤常用的增白剂CXT和CBS-X相比,BLF-3在水溶性、耐硬水性、耐酸、碱性、耐氧漂剂及氯漂剂性能和耐晒性等方面有更优异;对织物增白以及与表面活性剂和洗衣液体系的复配、去污增白等方面性能更佳。     

纯棉精漂工艺的改进

纯棉精漂工艺的改进王尉坤，杨振华南京化工学校南通海林针织厂南通海林针织厂纯棉精漂工艺，一直采用碱煮→氯漂→氧漂→复漂。该工艺流程较复杂，生产率低，劳动强度大，且产品质量难以控制。近年来，新型煮炼剂不断出现，须谨慎选择。对南京化工学校科技开发部研制的煮...     

烷基—过氧丁二酸的制备与应用

叙述了表面活性剂过氧酸漂白剂合成的新方法和α或β烷基一过氧丁二酸的制备,该烷基可为6～16碳原子的不饱和或饱和直链烷基,6～20碳原子的不饱和或饱和支链烷基,带有1或多个H,1～14碳原子烷基,F,Cl,NO_3,OSO_3M,SO_3M或COOM的饱和苯基团,该M为H,碱金属或铵阳离子。该合成烷基一过氧丁二酸的新方法比较经济,收率高,安全性好。该漂白合成物可用于漂白织物和其他洗涤目的。该漂白合成物还可含有过氧酸稳定剂、成型剂、填充剂和表面活性剂。     

机械力化学效应对麦草浆重组木聚糖酶生物漂白的影响

利用机械力化学作用,以提高木聚糖酶预处理效果。论文研究了磨浆对重组木聚糖酶预处理效果的影响;磨浆前后重组木聚糖酶预处理对浆料漂白性能的影响。研究结果表明:采用机械力化学作用酶处理时比较适合的磨浆时间为5 min,打浆度在30 oSR左右,在酶用量为5 IU/g时,脱木素率达到29.7%,与磨浆前酶处理相比,脱木素率提高了34.4%;磨浆前后的浆料经过重组木聚糖酶预处理,在后续漂白时漂至与对照浆相近白度时(72.6%ISO),分别节省了50%和57.1%用氯量,大大减轻了漂白废水对环境的污染;通过磨浆前后酶处理液高效液相色谱分析、浆料结晶度测定以及扫描电镜的观察,从理论上证实了重组木聚糖酶在助漂时的机械力化学效应,并为它的广泛应用提供了理论依据。     

麦草亚铵法氧脱木素浆蒽醌强化次氯酸盐漂白

对麦草亚铵法氧脱木素浆进行蒽醌强化的次氯酸盐漂白工艺的研究,结果表明:在所选四因素三水平漂白工艺中,影响纸浆白度和卡伯值的主要因素是用氯量,当用氯量为7%时,纸浆白度为71.1%ISO;另外,在50℃和80℃的条件下,对麦草亚铵法氧脱木素浆分别进行添加氨基磺酸和蒽醌的漂白研究,发现次氯酸盐漂白时添加蒽醌比添加氨基磺酸的漂白效果好,不仅漂白浆的白度和黏度均得到提高,而且脱木素能力也显示加强。     

A Model for Chlorine Dioxide Delignification of Chemical Pulp

Abstract

A phenomenon based model for chlorine dioxide delignification of chemical pulp is introduced. The pulp suspension environment is modeled using the concept of two liquid phases, one inside and the other external to the fiber wall. Physico-chemical processes taking place during delignification are implemented with thermodynamic, mass transfer and reaction kinetic models. A broad library of chemical reactions is introduced. Inclusion of each reaction is justified. The model response is tested against experimental laboratory delignification results (o-delignified birch pulp). The experimental data consists of kappa number, hexenuronic acid, inorganic oxy-chlorine compound, and organochlorine (AOX, OX) measurements at several time points during five delignification experiments. The model predictions are mainly in good agreement with the experimental results. The predictions regarding hypochlorous acid driven processes (HexA removal, organochlorine formation, chlorite and chlorate concentration) are somewhat incoherent, indicating that knowledge regarding the intermediately formed hypochlorous acid is presently insufficient.     

Development of Phenolic Lignin During ClO2 Bleaching of Kraft Pulp

The development of the phenolic lignin content in kraft pulp during ClO₂ bleaching was quantitatively determined by the periodate oxidation method. The effect of hypochlorous acid, an intermediate formed during chlorine dioxide bleaching, was eliminated by addition of sulfamic acid, a scavenger of hypochlorous acid. It was found that the number of free phenolic lignin groups per 100 lignin monomer units decreased from about 29 for unbleached kraft lignin to about 6.5 after 1 minute of ClO₂ bleaching. It was also shown that the in-situ generated hypochlorous acid created phenolic hydroxyl groups during chlorine dioxide bleaching. Since it was found that delignification by chlorine dioxide itself was mostly restricted to free phenolic lignin, these findings were used to explain the effect on delignification of addition order of chlorine and chlorine dioxide during bleaching of kraft pulp.     

黏胶纤维用落叶松溶解浆的清洁漂白

引言近年来,随着棉花价格的总体上涨和消费者对纺织材料舒适度的要求,给黏胶纤维带来了需求增长空间。作为黏胶纤维的原材料,国内目前的溶解浆产能难以满足客户需求。据统计,国内溶解浆存     

漆酶和木聚糖酶预处理对麦草浆漂白性能的影响

生物漂白主要目的在于通过对纸浆预处理,减少后续漂白时漂剂用量,降低漂白废水对环境污染,同时改善纸浆性能。通过漆酶/木聚糖酶体系(LXS)和重组木聚糖酶(X)对麦草浆预处理,比较它们对浆料脱木素能力和漂白性能的影响。结果表明:麦草浆经过两种酶预处理后,都能降低浆料卡伯值,而漆酶处理后降低的幅度更大,与原浆和木聚糖酶处理浆相比分别降低32.64%和6.47%,但是在木聚糖酶处理液中能检测到更多的还原糖;两种酶处理浆在后续漂白中漂白至与对照浆相近白度时均能节省50%漂剂用量,且能改善浆料物理强度;比较两种酶对浆料漂白性能的影响,则是在相同漂剂用量时木聚糖酶漂白浆的白度稍高,而浆料得率和强度稍低;两种酶处理浆料的纤维素结晶度测定表明酶处理前后浆料的纤维素的结晶结构没有明显的变化,而且纤维素的结晶度都有不同程度的提高。通过扫描电镜观察以及X射线光电子能谱(XPS)分析,从理论上说明两者脱木素的差异。     

慈竹机械浆（RMP）氨法预处理工艺研究

研究了在氨水中添加少量KOH或K3PO4预处理慈竹机械浆(RMP)的工艺。考察了预处理条件对酶解还原糖产率的影响。单因素实验得到氨水加KOH最佳预处理条件为:预处理温度120℃、固液比〔即1 g绝干浆加入液体的体积(mL),下同〕1∶6、时间3.5 h、氨水用量70%(即氨水质量占绝干浆质量的百分数,下同)、KOH用量5%(即KOH质量占绝干浆质量的百分数,下同)。在此最佳条件下,慈竹RMP的纤维素保留率为90.66%,半纤维素保留率为92.90%,木质素脱除率为41.05%;在pH=4.8、加酶量20 FPU/g预处理后底物、反应温度50℃的条件下酶解24 h,还原糖产率为23.95%,纤维素转化率为44.61%。虽然氨水加K3 PO4预处理酶解纤维素转化率可达56.95%,但是纤维素保留率仅为74.59%,与氨水加KOH相比,纤维素损失较大。     

氧脱木素效率的改善途径

氧脱木素被认为是除了硫酸盐蒸煮脱木素外,成本最低且最简单的脱木素方法,所以氧漂可以把制浆与漂白结合起来。且氧脱木素技术具有环境污染小、漂后纸浆质量高等优点,现已成为ECF和TCF漂白的主体工艺。氧脱木素是以分子氧为漂白剂,酚型木质素与O2反应从而消除侧链,打开苯环,脱甲基化而被氧化降解。该过程受到用碱量、反应温度、时间、氧压、浆浓等许多工艺参数的影响。为改善氧脱木素效果,研究者提出了多种方法,如两段氧脱木素、助剂强化氧脱木素及氧脱木素前预处理等。氧脱木素在我国的应用前景是很广阔的,而且环境保护法规的日益严格对实施氧脱木素技术也十分有利,因此对于氧脱木素的研究还需继续。     

低卡伯值麦草浆无氯漂白的研究

采用麦草硫酸盐法(KP法)一级蒸煮深度脱木素技术,制取低卡伯值麦草浆,并对其进行两种不同方式的无氯漂白。结果表明:AQ(PN)P流程可将浆料漂至白度86.2%(SBD),粘度为938mL/g。QZEYP流程能漂至86.9%(SBD),粘度为851mL/g。无氯漂白的粘度和白度稳定性均优于CEH三段漂。预处理对保护浆料有着重要作用。在过氧化氢漂白中,高温高压是脱木素和提高白度的必要条件。臭氧漂白是一种重要又经济的无氯漂白方法。     

Effect of xylanase on ozone bleaching kinetics and properties of Eucalyptus kraft pulp

Environmental pressure has led the pulp and paper industry to develop new technologies in order to reduce or suppress the presence of various pollutants in effluents from bleaching plants. One of the choices for this purpose is enzyme‐based biotechnology. This study deals with the effect of using a xylanase‐based enzymatic pretreatment, in a TCF (Totally Chlorine Free) sequence, on the properties of the resulting paper pulps. The hexenuronic acid content in the pulp and the physical properties of the paper were also studied. The performance of the xylanase was analysed through kinetic studies on ozone bleaching. The enzymatic pretreatment results in easier bleaching and delignification of the pulp, causing a bleach‐boosting effect. The decreased consumption of reagent is related to a decreased content of hexenuronic groups. The physical properties of the treated pulp are similar to those of untreated pulps. Cellulose degradation, delignification and chromophores' removal show first‐order kinetics. Enzyme pretreatment leads to differences between the kinetic constants of cellulose degradation and chromophores' removal, due to an increased accessibility to bleaching agents. The xylanase treatment leads to a lower floor kappa number (IK_∞) during the ozone stage. Copyright © 2003 Society of Chemical Industry