Application of New Modified Bentonite in Decolorization of Simulated Printing and Dyeing Wastewater

The problem of colority control of printing and dyeing wastewater has become a technical problem that plagues related companies.Bentonite is an adsorbent with excellent properties.Modification of bentonite with environmentally friendly substances can improve its decolorization performance.In this experiment,the simulated printing and dyeing wastewater was taken as the control object,and the bentonite was modified with environmentally friendly materials such as sodium carboxymethyl cellulose(CMC)and lignin to prepare a new modified bentonite;then the modified bentonite was used to adsorb the simulated wastewater to reduce the water colority and COD;finally the relevant design of the adsorption process was made.Results indicate that M lignin∶M CMC∶M original bentonite=1∶2∶97 had the optimum treatment effect,the optimum modification temperature was 30℃ and the modification time was 4 h;the optimum conditions for the adsorption process were:pH=5,temperature=30℃,reaction time=60 min,dosage=0.05 g of modified bentonite/mL simulated dye solution.The final removal rate of colority and COD reached 95.0% and 98.2%,respectively.Compared with the original bentonite,this new modified bentonite has greater adsorption capacity and thus has greater application value.

Construction and Application of Engineered Bacteria for Bioaugmentation Decolorization of Dyeing Wastewater: A Review

With the development of dyeing wastewater treatment biotechnology, the advantages of bioaugmentation bacteria gradually catch people’s eyes. Therefore, its construction and application research has also attracted the attention of the majority of scholars. This article summaries the construction and application of bioaugmentation engineered bacteria used to treat dyeing wastewater in recent years, including the screening, domestication and application of single and mixed flora bacteria. In addition, the impact of the strengthening effect of all genes is also described in this paper. Finally, the optimization and promoted use of bioaugmentation bacteria are out looked.

Fenton Reagent Generated in Electrolysis Cell and Its Usage in Degradation and Decolorization of Dyes

The Electro-chemistry process to produce Fenton reagents has been described. The in situ oxidation of dyes, acid chrome and alizarin red(Fenton reagents) with electrogenerated hydroxyl radicals was investigated. The \{ I-V \} cyclic voltammograms were measured. The redox peaks of the dyes were not observed in the treated dye solutions instead of a couple of O_2/H_2O_2 redox peaks. The IR results indicate that acid chrome dye was decomposed into naphthylamine and phenol aminophenol sulfonic acid. The degradation and the decolorization of the dyes were comfirmed by the visible spectrum and the chemical analysis. The COD_ cr removing rate was close to 80%.

Potential of plant polyphenol oxidases in the decolorization and removal of textile and non-textile dyes

In this study an effort has been made to use plant polyphenol oxidases; potato （Solanum tuberosum） and brinjal （Solanum melongena）, for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.

Decolorization on Indigo Dyeing Wastewater by Laccase from Coriolus versicolor

[ Object] The study aimed to discuss the decolorization on indigo dyeing wastewater by laccase from Coriolus versicolor. [ Method ] Firstly, the effects of temperature, pH, indigo concentration, HBT concentration, laccase dosage on the decolorization of indigo dyeing wastewater by laccase/HBT, and then the synergism of laccase and acid cellulase was analyzed. [Result] Using ABTS as the substrate, the kinetic parame- ters, K,, and Vmax, were 0.318 mmol/L and 0.035 5 mmol/（ L . min） respectively. The decolorization rate of indigo reached 96.5% when the lacca- se acted on indigo for 40 min with HBT as an introducer at temperature 50 ℃, pH =4.5, indigo concentration 100 mg/L, HBT concentration 0.1% and laccase dosage 100 lU/L. Due to the synergism of laccase and acid cellulase during the bio-finishing of blue jeans, the backstaining degree of blue jeans reduced by 85% when the amount of laccase added was 15 000 IU/kg. Menawhile, the synergism of the laccase and acid cellulase de- creased indigo concentration in wastewater by 83.8%. [ Conclusion ] The laccase from Coriolus versicolor had a good prospect in the bio-finishing of blue jeans and the decolorization of indigo dyeing wastewater.

Efficient decolorization of dye-containing wastewater using mycelial pellets formed of marine-derived Aspergillus niger

In order to improve the efficient decolorization of dye-containing water by biosorbent and understand the biosorption mechanism, the self-immobilization mycelial pellets were prepared using a marine-derived fungus Aspergillus niger ZJUBE-1, and an azo dye, Congo red was chosen as a model dye to investigate batch decolorization efficiency by pellets. The pellets as biosorbent showed strong salt and acid tolerance in biosorption process. The results for dye adsorption showed that the biosorption process fitted well with models of pseudo-second-order kinetic and Langmuir isotherm, with a maximum adsorption capacity of 263.2 mg·g^(-1) mycelium. During 6 batches of continuous decolorization operation, the mycelial pellets could possess efficient decolorization abilities(>98.5%).The appearance of new peak in the UV–Vis spectral result indicated that the decolorization process may also contain biodegradation. The mechanism studies showed that efficient biosorption ability of pellets only relies on the active zone on the surface of the pellet, which can be enhanced by nutrition supplement or be shifted outward by a reculture process.

Treatment of Dye Wastewater by Using a Hybrid Gas/Liquid Pulsed Discharge Plasma Reactor

A hybrid gas/liquid pulsed discharge plasma reactor using a porous ceramic tube is proposed for dye wastewater treatment. High voltage pulsed discharge plasma was generated in the gas phase and simultaneously the plasma channel was permeated through the tiny holes of the ceramic tube into the water phase accompanied by gas bubbles. The porous ceramic tube not only separated the gas phase and liquid phase but also offered an effective plasma spreading channel. The effects of the peak pulse voltage, additive gas varieties, gas bubbling rate, solution conductivity and TiO2 addition were investigated. The results showed that this reactor was effective for dye wastewater treatment. The decoloration efficiency of Acid Orange II was enhanced with an increase in the power supplied. Under the studied conditions, 97% of Acid Orange II in aqueous solution was effectively decolored with additive oxygen gas, which was 51% higher than that with argon gas, and the increasing 02 bubbling rate also benefited the decoloration of dye wastewater. Water conductivity had a small effect on the level of decoloration. Catalysis of TiO2 could be induced by the pulsed discharge plasma and addition of TiO2 aided the decoloration of Acid Orange II.

海藻酸钠固定漆酶复合淀粉处理模拟印染废水的应用

采用固定漆酶的海藻酸钠-钙离子交联水凝胶球与阳离子淀粉按质量比1∶1形成新型复合吸附剂,用于对模拟刚果红染料废水的研究。考察如吸附剂投加量、反应时间、pH值等条件对模拟印染废水吸附效果的影响。结果表明,在体积50 mL、转速125 r·min^(-1)的条件下,吸附剂用量为0.6 g、吸附时间30 min、pH值在6~7、反应温度为30℃、刚果红溶液初始浓度为100 mg·L^(-1),脱色率达到96.11%,吸附量为164.2 mg·g^(-1)。对比Freundlich吸附等温方程(R^(2)=0.9899)和Langmuir吸附等温方程(R^(2)=0.9982),表明此处理过程等温拟合模型更符合Langmuir吸附模型,为单层吸附。

磺化聚苯砜/聚砜纳滤脱色膜的制备及其性能研究

本文中引用一种新的高分子聚合物-磺化聚苯砜(SPPSU)制备纳滤脱色膜的涂覆层,将其与其余药品混合后制备成纳滤膜的表层涂覆液,从而制备成可分离开染料/无机盐混合液的纳滤脱色膜。经过优化调整SPPSU的浓度,磺化度,以及后处理温度三个变量,最终确定SPPSU浓度为1.5%,磺化度为35%,后处理温度为100℃时,其对刚果红的截留率最高可达99.6%,水通量最高可达142 L/(m^(2)·h),与此同时硫酸钠的截留率低于5%;在甲基蓝与硫酸钠的混合液处理过程中,甲基蓝的截留率为92.5%,水通量为75 L/(m^(2)·h),硫酸钠截留率在20%以下,实现了染料溶液与无机盐的有效分离,并在此基础上,将其与海德能的商业纳滤脱色膜进行对照,得出可以与HYDRACoRe10-LD的性能相似,而水通量却高出很多,说明此纳滤脱色膜有很好的应用前景。

PAC/PDM复合混凝剂对模拟印染废水混凝脱色效果研究

采用混凝烧杯实验,以脱色率和CODMn去除率为指标,研究特征黏度(0.63 dL/g、1.53 dL/g、2.63 dL/g)及复配比例(15:1、10:1、5:1)系列化的复合混凝剂PAC/PDM对模拟印染废水的混凝脱色效果和机理。结果表明,PAC/PDM具有良好的混凝脱色效果。其中,PAC/PDM(2.63/10:1)对活性红、活性蓝的混凝脱色效果最好,其最佳脱色率分别为98.67%、90.83%,最佳CODMn去除率分别为86.44%、80.79%;PAC/PDM(0.63/15:1)对分散红、分散深蓝的混凝脱色效果最好,其最佳脱色率分别为99.30%、99.18%,最佳CODMn去除率分别为86.49%、86.41%。结合Zeta电位测定及絮团形貌观察,PAC/PDM处理模拟印染废水的混凝机理主要是电中和吸附架桥。

PA/PDA/CPVC复合纳滤膜的制备及其在模拟染料废水处理中的应用

以氯化聚氯乙烯(CPVC)超滤膜为基膜,将多巴胺(DA)和聚乙烯亚胺(PEI)共沉积后,与均苯三甲酰氯(TMC)进行界面聚合制备了聚酰胺/聚多巴胺/氯化聚氯乙烯(PA/PDA/CPVC)复合纳滤膜。通过傅里叶变换红外光谱仪、扫描电子显微镜、原子力显微镜、接触角仪对PA/PDA/CPVC复合纳滤膜选择层的化学结构、微观结构、表面粗糙度及亲水性进行了表征,探讨了PEI质量浓度对复合纳滤膜结构和性能的影响。研究结果表明:随着PEI质量浓度的增大,复合纳滤膜表面变得光滑、亲水性增强,通量先增大后减小;PEI质量浓度为5g/L时,复合纳滤膜的通量达到最大。PA/PDA/CPVC复合纳滤膜对染料活性黑5(RB5)的截留率皆高于94%,而对NaCl的截留率低于5.6%,说明该复合纳滤膜能够对染料和盐进行较好的分离,复合纳滤膜在模拟RB5染料废水处理中稳定性良好。

中空纤维纳滤膜在染料分离应用中的研究进展

印染行业产生了大量富含染料的高盐废水,中空纤维纳滤膜的选择性分离特征有望实现染料和无机盐的高效分离,进而完成印染废水的污染治理和有价资源的同步回收,且与传统的卷式膜相比还具有填充密度大和自支撑的优势,因而在印染废水处理领域得到了日益广泛的关注。回顾了近年来中空纤维纳滤技术在染料分离过程中的研究进展,重点探讨了适用于染料分离的疏松型和荷正电中空纤维纳滤膜材料的制备,分析了中空纤维纳滤膜在染料分离过程中的膜污染特性以及相应的膜污染控制措施。最后对未来的研究方向进行了展望,以期进一步推动中空纤维纳滤膜技术在染料废水处理中的推广与应用。

“膜”法:丑小鸭(污水)变白天鹅(清水)——纳滤膜制备及其分离性能测试科普

膜分离作为前沿分离技术,是实现国家水生态治理和绿色发展的关键。本实验以纳滤膜分离技术为代表,通过直观演示纳滤膜制备方法以及纳滤膜对硫酸钠盐和不同染料污水(刚果红、甲基蓝、活性黑和维多利亚蓝染料污水)的分离性能,为中小学生和普通大众科普前沿分离技术,并体会化学材料之美。本实验过程操作简单,仅仅通过简单的“泡一泡”,“晾一晾”和“烘一烘”便可制备得到纳滤膜。此外,纳滤膜分离测试装置可以自行组装,可操作性强。最后,纳滤膜分离现象明显,具有很强的趣味性。借助该实验过程的演示:一方面,让大众对纳滤膜制备方法和其分离原理有所了解;另一方面,有助于加深大众对“绿水青山就是金山银山”和“绿色发展”等重要理念的理解。

Microwave-assisted Fenton-like decolorization of methyl orange solution using chromium compounds

Azo dyes discharged in the environment are persistent organic pollutants (POPs),which are very difficult to remove. We developed a microwave-assisted Fenton-like process to degrade methyl orange (MO),an azo dye,with hydrogen peroxide (H2O2) catalyzed by chromium compounds coexisting with MO in the solution. Comparison between the Cr(Ⅲ)-H2O2 and Cr(VI)-H2O2 systems shows that Cr(VI) has a stronger and more stable catalytical activity than Cr(Ⅲ),and Cr(Ⅲ) is more susceptible to a change in the acidity or alkalinity of the reaction system. With a Cr(VI) concentration of 10 mmol L-1 or a Cr(Ⅲ) concentration of 12 mmol L?1 in the solution under the microwave irradiation of a power larger than 300 W for 3 min,10 mmol L-1 H2O2 can degrade more than 95% of 1 000 mg L-1 methyl orange; when the microwave power is increased to 700 W,the same amount of H2O2 can degrade all methyl orange in the solution with the same amount of Cr(VI) catalyst. Ultraviolet-visible spectrography indicates the cleavage of the azo bond in methyl orange after treatment,suggesting the potential of this Fenton-like process to degrade azo dye POPs. Reusing waste chromium compounds coexisting with dyestuff in wastewater to catalyze the degradation of azo dyes could be a cost-effective technique for azo dyes and chromate manufacturers and/or users to treat their wastewater and prevent POPs from endangering the environment. This is of particular importance to controlling the water quality of the Three Gorges Reservoir.

混凝法处理印染废水的研究

采用混凝剂Al_(2)(SO_(4))_(3)·18H_(2)O处理大红染料废水,通过改变药剂的投加量、搅拌转速、废水浓度及p H值等,探索其对废水色度的去除效果及最佳工艺创新。实验结果表明:混凝剂Al_(2)(SO_(4))_(3)·18H_(2)O在处理大红染料废水时表现出较好的脱色性能,当混凝剂投药量为0.12 g时,脱色效果最好,为93.10%;当搅拌速度为350 r/min,搅拌时间为2 min时,废水脱色率效果最佳,为95.65%;当废水p H值为7.0时,废水脱色效果最好,为97.50%;当废水为酸性或者碱性时,脱色效果较差。当印染废水浓度为0.80 g/L时,脱色效果最佳,为92.73%。

活性染料染色废水的循环染色

针对活性染料染色工艺流程长,能耗水耗高和有色废水排放量大等问题,使用有色废水处理剂对活性染料染色织物进行低温快速皂洗并实现循环染色。以模拟废水和染液为研究对象,脱色率为评价指标,探究了染色废水处理工艺。通过测试染料竭染率、固色率和染色织物部分颜色参数证实了染色废水循环染色的可行性。结果表明:0.07 g/L的C.I.活性红218模拟废水适宜的处理条件是3%废水处理剂,85℃处理15 min,在此条件下染色废水脱色率高达99.1%;与常规染色相比,利用处理后的废水进行循环染色,可提高活性染料上染百分率,染色织物颜色偏深;染色时,染料上染百分率和固色率随循环次数增加呈现增大的趋势。使用该方式染色既能实现有色废水高效处理,又能实现无机盐重复利用,符合低碳环保要求。

PA/PET/PDA/PVDF复合纳滤膜制备及其处理染料废水的研究

为提高PA/PDA/PVDF(聚酰胺/聚多巴胺/聚偏氟乙烯)纳滤膜选择层的疏松程度,在水相单体多巴胺(DA)与聚乙烯亚胺(PEI)中添加β-环糊精(β-CD),通过β-CD与均苯三甲酰氯(TMC)聚合生成的聚酯(PET)调控PA/PDA选择层的微观结构,从而制得PA/PET/PDA/PVDF复合疏松纳滤膜。考察了β-CD添加量对复合纳滤膜微观结构、表面粗糙度与过滤性能的影响,并对复合纳滤膜化学结构和膜表面亲水性进行了表征,同时对复合纳滤膜处理模拟活性黑5(RB5)染料废水的效果进行了探讨。结果表明,β-CD能明显改善PA/PET/PDA/PVDF复合纳滤膜选择层的疏松程度和亲水性;随β-CD添加量增加,复合纳滤膜表面粗糙度增大,亲水性、纯水和染料通量增加,对染料和盐的截留率逐渐降低。综合考虑β-CD浓度对模拟RB5溶液通量和截留率的影响,β-CD的最佳质量浓度为1 g/L,在最佳条件下制备的纳滤膜对RB5的截留率达96.4%,对NaCl的截留率仅为2.9%,染料与盐的分离因子为33.2。

漆酶及其对染料废水处理的研究进展

染料废水具有色度高、产量大、毒性强和难生物降解等特点,对废水进行脱色及去除化学需氧量(COD)是此类工业废水处理的重点。染料废水的处理方法有物理、化学及生物方法,主要包括絮凝沉淀、水解酸化和活性污泥法等,这些方法往往具有成本高、能耗大、反应条件剧烈以及二次污染等缺点。酶与酶技术的开发与应用是环境生物技术中重要的部分,为环境污染治理提供了新的技术手段。漆酶是处理染料废水最具潜力的生物酶之一,对多种合成的和天然的染料分子具有较高的脱色效率。本文介绍了漆酶的来源、结构、分类以及催化机制等,综述了真菌漆酶和细菌漆酶对染料废水中占比最大的偶氮染料和蒽醌染料进行实际脱色和脱毒处理的研究现状,并对未来的研究方向进行展望。

二氧化钛光催化降解印染废水研究

以钛酸丁酯钛源,采用溶胶-凝胶法合成了二氧化钛催化剂,使用XRD表征了催化剂的结构,以印染厂二级生化处理后的印染废水作为降解对象,研究了催化剂对印染废水光催化性能。结果表明,XRD测试证明成功合成了锐钛矿二氧化钛。二氧化钛催化剂对印染废水色度和COD去除率达到94%和89%,并好于P25催化剂。当溶液呈碱性时,更利于对印染废水色度和COD得分去除;催化剂循环使用6次后,其脱色率和COD去除率依然维持在90%以上,具有良好重复使用性能。

助剂对CG催化体系活性染料染色废水脱色的影响

将自制的生物高分子催化剂CG和双氧水加入到活性艳蓝BRV模拟染色废水中,构建催化脱色体系,探究染色废水中存在不同用量的盐、碱、酸、氧化剂和还原剂等对该体系脱色效果的影响。结果表明:染色废水中含有一定量的盐(氯化钠、硫酸钠)、碱(少量氢氧化钠,染液pH小于11)、酸(盐酸)、氧化剂(过硫酸铵)对CG/双氧水催化体系脱色有利;染色废水中含有碳酸钠、少量氧化剂高锰酸钾或还原剂亚硫酸氢钠对CG/双氧水催化体系脱色影响不大。说明CG/双氧水催化体系对复杂成分的染色废水都有良好的脱色效果。但CG/双氧水催化体系中含有大量氢氧化钠(染液pH大于11)对脱色不利。此外,催化剂CG与氧化剂过硫酸铵组成的催化氧化体系,以及催化剂CG与还原剂亚硫酸氢钠组成的催化还原体系对活性染料染色废水也有良好的脱色效果。而且研究表明,催化剂CG/双氧水体系对含有盐和碱的模拟活性染料染色废水具有良好的脱色效果,其最佳脱色工艺为:催化剂CG用量为0.5 g/L,40℃脱色处理30 min。