新生态MnO2吸附法处理水溶性阴离子染料废水的研究

研究了各种水溶性阴离子染料在新生态MnO2表面的脱色作用。结果表明,9种不同模拟染料废水(包括直接染料、酸性媒介染料、活性染料)的脱色效果均十分显著．且脱色过程受pH的影响较大。另外。通过CHN元素分析、差热分析、紫外光谱及滴定分析等测试手段．初步认为在酸性介质下．新生MnO2质子化的表面可以吸附阴离子型染料,从而将其去除。     

含氮芳香化合物的厌氧生物降解研究回顾

回顾了硝基芳香化合物和偶氮化合物在厌氧条件下的生物脱毒、转化和矿化作用的研究成果。这些研究表明 ,由于硝基和偶氮基具有强烈的吸电子性 ,好氧条件下很难降解。但是 ,硝基和偶氮基芳香化合物在产甲烷菌群作用下较易还原脱毒 ,转化为相应的芳香胺类 ,其毒性要小几个数量级 ,因而有些毒性很高的芳香化合物废水可利用厌氧反应器处理 ,而且反应过程中发现一些芳香胺类化合物可被完全矿化 ,表明一些含氮芳香化合物可作为厌氧菌的碳源和能源 ,在厌氧条件下被完全生物降解。     

Treatment of anthraquinone dye wastewater by hydrolytic acidification-aerobic process

Experiment on microbial degradation with two kinds of biological process, hydrolytic acidification-aerobic process and aerobic process was conducted to treat the anthraquinone dye wastewater with CODc, concentration of 400 mg/L and chroma 800. The experimental result demonstrated that the hydrolytic-aerobic process could raise the biodegradability of anthraquinone dye wastewater effectively. The effluent CODc, can reach 120-170 mg/L and chroma 150 which is superior to that from simple aerobic process.     

Photocatalytic degradation of dye effluent by titanium dioxide pillar pellets in aqueous solution

Photocatalytic oxidation (PCO) process is an effective way to deal with organic pollutants in wastewater which could be difficult to be degraded by conventional biological treatment methods. Normally the TiO2 powder in nanometre size range was directly used as photocatalyst for dye degradation in wastewater. However the titanium dioxide powder was arduous to be recovered from the solution after treatment. In this application, a new form of TiO2(i. e. pillar pellets ranging from 2.5 to 5.3 mm long and with a diameter of 3.7 mm) was used and investigated for photocatalytic degradation of textile dye effluent. A test system was built with a flat plate reactor(FPR) and UV light source(blacklight and solar simulator as light source respectively) for investigating the effectiveness of the new form of TiO2. It was found that the photocatalytic process under this configuration could efficiently remove colours from textile dyeing effluent. Comparing with the TiO2 powder, the pellet was very easy to recovered from the treated solution and can be reused in multiple times without the significant change on the photocatalytic property. The results also showed that to achieve the same photocatalytic performance, the FPR area by pellets was about 91% smaller than required by TiO2 powder. At least TiO2 pellet could be used as an alternative form of photocatalyst in applications for textile effluent treatment process, also other wastewater treatment processes.     

新生态MnO2吸附剂对酸性媒介染料废水脱色特性研究

本文主要报道了一种用于染料废水处理的新型材料即新生态MnO2 及其对三种酸性媒介染料染色废水的脱色作用及影响脱色效果的主要因素。研究结果表明 ,新生态MnO2 对酸性媒介染料的吸附能力很强 ,当染料浓度为2 0 0mg/L、pH <2时 ,其对酸性媒介黑T、酸性媒介绿G和酸性媒介黄GG的脱色率分别达 98.2 %、94.5 %和 96 .4%。染料吸附效果受体系pH值、MnO2 投加量、吸附时间及温度等因素的影响 ,其中pH值是最主要的影响因素。新生态MnO2 对酸性媒介黄GG的吸附作用符合Langmuir吸附等温式     

Fe3O4@SA/Ce微球的表征及对染料的吸附特性

以天然高分子化合物海藻酸钠(sodium alginate,SA)为骨架,结合磁性Fe₃O₄和稀土铈离子Ce(Ⅲ)通过溶液反应制备出一种新型的磁性海藻酸铈复合微球(Fe₃O₄@SA;Ce).采用X射线衍射(XRD)、孔结构比表面积分析(BET)、扫描电子显微镜(SEM)、红外光谱(FT-IR)及振动样品强磁计(VSM)对Fe₃O₄@SA;Ce的结构进行了表征,并以直接桃红12B(direct red 12B,DR 12B)和直接橙S(direct orange S,DO S)两种染料为吸附对象,探讨了Fe₃O₄@SA;Ce的吸附剂性能、吸附动力学和热力学.结果表明,Fe₃O₄@SA;Ce对室温下自然pH染料溶液中DR 12B和DO S均表现出良好的吸附效果,吸附量分别可达464 mg·g^-1和730 mg·g^-1.在不同温度下(298、313、328 K),Fe₃O₄@SA;Ce对DR 12B和DO S的吸附过程均可用拟二级吸附动力学方程准确描述.通过等温吸附研究,发现Fe₃O₄@SA;Ce对两种染料的等温吸附较好地符合Freundlich模型.各种表征结果表明,SA与Ce(Ⅲ)和Fe₃O₄交联反应后生成的Fe₃O₄@SA;Ce凝胶球表面有大量深浅不一的褶皱沟纹,形貌发生了显著变化.作为一种绿色环保、制备方法简单、可高效吸附的磁性高分子复合吸附剂,Fe₃O₄@SA;Ce对高浓度染料具有很好的吸附效果,期望能够在染料废水处理中得到广泛应用.     

Indian dye yielding plants: Efforts and opportunities

The present review article deals with the information on the dye‐yielding plants of India. Dyes are intensively coloured compounds that are applied to a substrate such as fibre, paper, cosmetics, hair, etc. to give colours and can be extracted from the roots, fruits/berries, bark, leaves, flowers, and stem/wood, fungi, and lichens by various processes of extractions. In addition to their dye‐yielding characteristics, many of these plants possess medicinal values and can be used for multiple other purposes. Plant derived‐colours have an important role in human life because of their safe and eco‐friendly nature. But due to the availability of economically cheaper synthetic dyes, the indigenous knowledge of extraction, processing, and proper utilisation has been diminished. Nowadays, the demand for natural dyes has been increased worldwide due to awareness about their beneficial properties. It has been essential that proper documentation and measure of conservation should be undertaken to preserve these natural dye‐yielding plants. This review article is an aid to a collective inquiry into Indian dye plants.     

Nanosized magnetite in low cost materials for remediation of water polluted with toxic metals,azo- and antraquinonic dyes

Nanosized magnetite has emerged as an adsorbent of pollutants in water remediation. Nanoadsorbents include magnetic iron oxide and its modifiers/stabilizers, such as carbon, silica, clay, organic moieties (polymers, aminoacids, and fatty acids) and other inorganic oxides. This review is focused on the recent developments on the synthesis and use of magnetic nanoparticles and nanocomposites in the treatment of contaminated water. The emphasis is on the influence of the iron oxide modifiers on some properties of interest such as size, BET area, and magnetization. The characteristics of these nanomaterials are related to their ability to eliminate heavy metal ions and dyes from wastewater. Comparative analysis of the actual literature was performed aiming to present the magnetic material, its preparation methodology and performance in the elimination of the selected pollutants. Vast information has been properly summarized according to the materials, their properties and preferential affinity for selected contaminants. The mechanisms governing nanomaterial’s formation as well as the interactions with heavy metals and dyes have been carefully analyzed and associated to their efficiency.     

Removal of congo red and basic violet 1 by chir pine (Pinus roxburghii) sawdust,a saw mill waste: batch and column studies

The efficiency of chir pine sawdust (CPS) for adsorptive removal of the dyes, congo red (CR) and basic violet 1 (BV), from aqueous solution was evaluated using batch and column studies. The equilibrium was attained in 60 min for CR and 45 min for BV. The adsorption of BV obeyed the Langmuir isotherm model while the Freundlich isotherm fitted the equilibrium data of CR adsorption. The Langmuir monolayer adsorption capacities (Q_o) of CPS for BV and CR were 11.3 and 5.8 g kg^?1, respectively. The kinetic data for CR were best fitted to the Lagergren pseudo-first-order model and for BV to the pseudo-second-order model. The intra-particle diffusion was found to be the rate-controlling step for CR adsorption, while the adsorption kinetics of BV were controlled by both intra-particle and liquid-film diffusion. The thermodynamic parameters indicated that the adsorption process was spontaneous and endothermic in nature. The adsorption activation energy (E_a) for CR (124 kJ mol^?1) implied chemical adsorption while that for BV (5.4 kJ mol^?1) indicated physical adsorption. An increase in the Thomas model constant (K_Th) with increasing flow indicated that for both dyes the mass transport resistance decreased during adsorption. Thus, CPS may be an efficient low-cost adsorbent for decolorization of dye-containing wastewaters.     

Structural effect on photocatalytic degradation of metallised azo dyes in aqueous TiO2 suspension

Three metallised azo dyes were investigated under TiO₂‐photocatalytic and photosensitised conditions in aqueous buffering solutions. The degradation follows apparent first‐order kinetics. The size and strength of intramolecular conjugation determine the light‐fastness of the investigated dyes. Compared with ¹O₂ produced in photosensitised process, the more powerful *OH radicals in TiCO₂ photocatalytic process are highly reactive towards the investigated azo dyes. And as a result, the TiO₂‐photocatalysis makes little less distinction in the degradation kinetic data of the azo dyes compared with the photosensitised degradation of them.