Cathodic decolourization of textile dyebaths: Tests with full scale plant

Direct cathodic reduction of azo dyes permits decolourization of intensively coloured textile wastewater without addition of chemicals or formation of sludge. The technique is of particular interest for the treatment of concentrated dyebaths from pad batch-dyeing with reactive dyes which contain on average about 50 g L^–1 of dyestuff. On the basis of laboratory scale experiments with model dyebaths and dyebath samples from technical application a scale-up was performed. A multicathode electrolyser for a maximum cell current of 150 A successfully was tested in a dyehouse. The treatment capacity of the installed electrolyser was 1 m³ of used concentrated dyebath per day. This corresponds to the full amount of such concentrates which have to be treated in a medium sized dyehouse. By cathodic decolourization the absorbance of the concentrated dyebaths was lowered to approximately 20% of the initial value with an energy consumption of 20–25 kWh m^–3.     

Cathodic decolourisation of textile waste water containing reactive dyes using a multi‐cathode electrolyser

The reductive decolourisation of textile dyestuffs containing an azo group was investigated by direct cathodic electron transfer CI Acid Red 27 and CI Acid Yellow 9 were used as model compounds for azo dyes. Reactive dyes, eg CI Reactive Red 4, CI Reactive Orange 4, and CI Reactive Black 5, which are in technical use for cellulose dyeing were investigated as representatives of practical importance. A basic characterisation of the reduction–decolourisation behaviour of the dyes was achieved by redox titration with Fe(II)–triethanolamine as reducing agent and parallel spectrophotometric observation of changes in the chromogenic system. From the redox titration experiments basic data describing the experimental conditions for successful cathodic electron transfer can be derived. The electrochemical dyestuff reduction experiments were performed in batch trials using a multi‐cathode electrolyser with high cathode area. According to the typical composition of such dyebaths 0.12 mol dm^?3 NaOH was used as ground electrolyte. The absorbance of the investigated dyestuff solutions could be decreased to below 20% of the initial value. For a 50% decrease in absorbance, electrical energy of about 6 kWh m^?3 is consumed. The process is of particular interest for the treatment of concentrated dyestuff solutions as they are used in continuous dyeing processes. © 2001 Society of Chemical Industry     

Decolourisation of Orange II by a Wood-Rotting Fungus

The decolourisation of Orange II by a wood-rotting fungus has been studied. It was found that Fungus F29 could effectively decolourise Orange II especially when grown as pelleted mycelia under agitated conditions. Many factors affecting the decolourisation process in nitrogen-limited media (NLM) were studied, including: concentration of glucose, NH₄⁺, Mn(II) and veratryl alcohol; initial pH; amount of mycelium; mycelial age; Orange II concentration; temperature. Results showed that the media containing Orange II at 1000 mg dm⁻³ (or higher) could be decolourised by 98% of the initial colour (A_{480 nm}) in 2 days, in most conditions tested, and that the mycelia could be repeatedly reused. © 1997 SCI.     

Effect of Color and Surfactants on Nanofiltration for the Recovery of Carpet Printing Wastewaters

Abstract

Carpet printing wastewater (CPW) was spiked with metal‐complex dyes at concentrations of 10 and 30 mg/L to investigate the effect of feed color on separation performance of nanofiltration (NF). The rejection was excellent; 98–100% for color and COD under all spiking conditions. Although the flux decline increased with increasing dye concentration, the concentration polarization was the main cause of the flux decline. The effect of surfactants on NF separation performance was also investigated by preparing synthetic wastewaters with dyes and auxiliary chemicals. The presence of a non‐ionic penetrant did not adversely affect the color rejection whereas the COD rejection was reduced from 100% to 91%. Furthermore, fouling became dominant when surfactants were used.     

P型活性染料用于棉织物印花的性能评价

为了评价P型活性染料用于棉织物印花性能,本文进行了该染料在棉织物上的印花实验,优化了实验条件,测试了印花布的各项色牢度、提升性和相对强度.结果表明:P型活性染料溶解度≥150 g/L,不溶物含量<0.2%,用于棉织物印花的最佳性能为白底沾色牢度4～5级、摩擦色牢度4～5级、皂洗色牢度4～5级、提升率100%、相对强度1...     

纺织品中禁用偶氮染料的检测方法优化

在最新的纺织品国家标准检测方法下,采用气相色谱/质谱(GC/MS)联用法,通过优化色谱程序升温条件,对23种禁用偶氮染料进行检测。结果 23种禁用芳香胺得到较好分离,相对标准偏差(RSD)为4.2%~7.8%。各种芳香胺浓度在5~50μg/mL范围内与色谱峰面积呈现良好的线性关系,相关系数大于0.9907。方法的总运行时间为33 min。该方法实现了禁用偶氮染料的快速、准确测定,适于大批量样品的分析。     

J酸的合成及其在直接染料、活性染料中的应用

本文论述了J酸的合成方法,探讨了J酸制备过程中副产物γ酸的生成过程及其控制方法.根据《世界染料品种—2005》公开的染料品种结构,对于J酸及其衍生物在直接染料和活性染料中的使用情况做了分析.     

活性染料及其真丝绸印染工艺探讨

研究了活性染料对丝绸进行染色和印花的工艺，提高了丝绸染色产品的色牢度、染深性、得色量和提升力。优选了酸浴法、中性浴法和碱浴法染色工艺条件以及印花工艺条件。指出一氟三嗪活性基优于一氯三嗪活性基，双活性基优于单活性基。国产活性染料应在溶解度、配套助剂、染料筛选等应用方面要加强研究。     

印染行业废水处理存在问题及对策

分析了印染加工过程各工序废水排放的特点,对国内外的印染废水处理现状进行了调查对比,总结了国内印染废水行业处理存在的问题,最终提出应摒弃单纯末端治理的传统方式,通过引入清洁生产理念、改善工艺、更新设备以及采取以废治废、资源化治理的后续处理方式,将印染行业废水治理作为一系统工程进行综合整治。     

Extraction of Azo Dyes from Aqueous Solutions with Room Temperature Ionic Liquids

In this work, ionic liquids/water distribution ratios (D) of azo dyes, including 1-(phenylazo)-2-naphthol, 1-(2-pyridylazo)-2-naphthol, 4-(nitrophenylazo)resorcinol, 4-(2-pyridylazo) resorcinol, and 2-(4-dimethylaminophenylazo) benzoic acid, have been determined experimentally. It was found that the D values are highly influenced by the pH of the water phase and the type of salts added. They increase with increasing alkyl chain length on the cations of the ionic liquids, and the anionic effect follows the order [BF₄]^? > [PF₆]^?. Possible extraction mechanism and selective separation of some azo dyes are also investigated. The results suggest that ionic liquids have potential applications in the removal and selective separation of azo dyes from water.     

活性染料印花用合成增稠剂的研制

用反相乳液聚合方法,以“C_(?)—r射线引发而得到一种新型活性染料印花增稠剂。并研究了辐照剂量,辅助单体、交联剂用量及水相的PH值对乳液的增稠性和耐电解质性的影响,运用正交设计总结出了最佳反应条件,结果证明合成增稠剂代替天然品是可行的。     

印染废水的传统处理方式评析

印染废水具有水量大、有机污染物含量高、碱性大、水质变化大等特点,属难处理的工业废水之一。从物理处理法、化学处理法,生物处理法等阐述了印染废水的传统处理方式,评释了它们各自的特点和存在问题,并对这些处理的发展提供一些参考意见,展望了印染废水处理技术的应用前景。     

水溶性荧光染料溶液脱盐浓缩的纳滤实验研究

选用NTR7450和NF270两种纳滤膜对水溶性工业荧光染料原液进行分离，选择出透过通量大、除盐效果好和染料截留率高的纳滤膜，并对该染料溶液进行了脱盐和浓缩的间歇渗滤过程研究：在温度25℃和压力1.0MPa下，膜对染料截留率达到100％，最终料液中NaCl浓度从0.214mol／L降到0.0025mol／L,料液被浓缩了2．6倍。说明纳滤膜的间歇渗滤操作过程能够实现染料溶液的脱盐浓缩。     

数码印花的现状及发展趋势

本文介绍了纺织品数码印花的发展及现状、数码印花的技术特点和数码印花优劣势。对数码印花的发展前景进行了展望。     

涤/棉混纺织物分散/活性染料一浴染色工艺研究

本实验选择双一氯均三嗪结构的活性染料和耐碱型分散染料,探讨涤/棉(65/35)混纺织物分散/活性染料一浴染色工艺。通过单因素实验分析了染色温度、染色时间、无水硫酸钠浓度和碳酸钠浓度对织物染色效果的影响,得到优化的工艺。红色在硫酸钠60 g/L、碳酸钠2 g/L、温度120℃、时间30分钟工艺条件下染色;蓝色在硫酸钠浓度45 g/L、碳酸钠浓度2g/L、温度130℃、时间60分钟工艺条件下染色。     

添加剂对喷墨印花用液态活性染料性质的影响

对喷墨印花用液态染料而言,助剂对其性能的改善有很大的作用,但同时助剂的添加又会对液态染料本身的性质产生影响。本文通过对液态染料溶解性、上染性和固色性的测试,考察了有机溶剂、助溶剂和表面活性剂对液态染料性质的影响。结果表明,对于有机溶剂,当其浓度适当时,不会影响染料的溶解度,并能改善液态染料的上染和固色性能;而助溶剂及表面活性剂对液态染料性质的影响则随助剂种类及用量的不同而不同。     

新型脱色絮凝剂(KD-800)处理印染废水的研究

探讨了一种新型有机高分子脱色絮凝剂(KD-800)的制备方法。KD-800与钢铁酸洗废液和聚丙烯酰胺联合使用,对以活性染料为主要成分的印染废水进行混凝脱色试验,对脱色影响因素和控制条件等进行了研究。结果表明,当K型KN型活性染料废水的pH值为6．0～11．0,KD-800用量为1．2mL/L,钢铁酸洗废液用量为2．5mL/L时．对活性染料废水的脱色率均可达到95％以上。     

纳滤膜技术在水处理中的应用

对纳滤膜的定义、特点、分离机理等作了介绍。综述了纳滤膜在工业废水处理、饮用水净化、水软化等方面的研究应用进展,并对纳滤膜分离技术的应用前景进行了展望。     

广东省纺织印染行业节能减排现状及技术需求

介绍了广东省纺织印染行业节能减排的现状,分析了目前的技术需求,提出了纺织印染行业节能减排技术的发展重点。     

分散染料的近期进展

介绍了分散料的近期进展,包括原有涂纶织物着色用散染料,超细旦纤维用分散染料,以及分散染料在喷射打印墨水和热转称铖像上的应用,展望了分散染料今后的发展方向。