Differential fate of metabolism of a disperse dye by microorganisms Galactomyces geotrichum and Brevibacillus laterosporus and their consortium GG-BL

The present work aims to evaluate Brown 3 REL degrading potential of developed microbial consortium GG-BL using two microbial cultures, Galactomyces geotrichum MTCC 1360 (GG) and Brevibacillus laterosporus MTCC 2298 (BL). Microbial consortium GG-BL showed 100% decolorization of a dye Brown 3 REL, while individually G. geotrichum MTCC 1360 and B. laterosporus MTCC 2298 showed 26% and 86% decolorization under aerobic condition (shaking) respectively. Measurements of biochemical oxygen demand (BOD) (76%) and chemical oxygen demand (COD) (68%) were done after decolorization by consortium GG-BL. No induction in activities of oxidoreductive enzymes found in G. geotrichum while B. laterosporus showed induction of veratryl alcohol oxidase, Nicotineamide adenine dinucleotide-dichlorophenol indophenol (NADH-DCIP) reductase and riboflavin reductase indicating their role in dye metabolism. Consortium GG-BL showed induction in the activities of laccase, veratryl alcohol oxidase, tyrosinase, NADH-DCIP reductase and riboflavin reductase. Two different sets of induced enzymes from G. geotrichum and B. laterosporus work together in consortium GG-BL resulting in faster degradation of dye. The degradation of Brown 3 REL was analyzed using high performance thin layer chromatography (HPTLC), high performance liquid chromatography (HPLC), Fourier transform infrared spectroscopy (FT-IR) and gas chromatography mass spectroscopy (GC-MS). Phytotoxicity study revealed that metabolites formed after degradation was significantly less toxic in nature.     

改性膨润土处理酸性大红的实验研究

文章对膨润土分别进行了钠化、酸化和铁柱撑改性的研究,并利用改性后的膨润土处理酸性大红模拟废水,比较了不同改性后膨润土处理模拟废水的效果,确定较优的改性方法和最佳反应条件。实验结果表明,酸改性膨润土对酸性大红模拟废水的处理效果优于钠化改性膨润土和铁柱撑改性膨润土。对于50 mL酸性大红模拟废水,在酸改性膨润土的投加量为1.0 g、pH为3、反应时间为60 min时,COD去除率可达65%以上,色度去除率可达85%以上。     

Decolorization of methyl orange in wastewater with in situ electrogenerated oh free radicals

A treatability study was conducted to determine the potential of white rot fungi to remediate soil from a Superfund site that had been contaminated with DDT. A tiered approach was utilized, starting with simple laboratory studies to screen the potential of white rot fungal strains to degrade DDT and culminating with a soil pan study that simulated land farming. Results from early tiers of the study indicated that Phanerochaete sordida had the best potential for remediating the soil. In the soil pan study, the fungus ultimately grew very well after second inoculation. However, the good growth did not translate to higher DDT removal compared to removal in pans that were not inoculated. ¹⁴[DDT] fate studies indicated the small amount of removal that did occur for both fungal inoculated and non‐inoculated conditions could be partially attributed to incorporation into humic material. Addition of a surfactant to the soil enhanced the removal of DDT in both inoculated and non‐inoculated soil. Consequently, under simulated land fanning conditions, this strain of fungus was not successful in remediating this soil.     

新型生物电Fenton法降解偶氮染料：铁复合碳毡阴极研究

传统电Fenton反应通过电化学方法产生H2O2,需外加电源,能耗大,成本高。基于MFC持续产电并可驱动阴极电Fenton系统运行的特点,本研究以铁复合碳毡为阴极电极,构建了微生物燃料电池驱动的生物电Fenton系统,探讨了铁复合碳毡及阴极pH对偶氮染料(金橙I号)脱色的影响。结果发现,铁复合碳毡脱色效果均好于普通碳毡。当pH为3时,4 h后Fe@Fe2O3/CF阴极脱色率达91.7%,明显高于α-FeOOH/CF和FeAlSi/CF的83.4%和69.9%。扫描电镜发现,Fe@Fe2O3以微粒状结构附着于碳毡表面,比表面积增大,可能是Fe@Fe2O3/CF脱色性能改善的主要原因。研究表明,低pH有利于生物电Fenton反应的进行。当pH由3.0提高至5.0时,Fe@Fe2O3/CF阴极脱色率降低至47.1%。阴极室染料脱色与阳极室废水TOC削减呈线性相关,说明阳极生物氧化是驱动阴极生物电Fenton反应的原动力。本研究提供了一种能自我维持、无需外源电力的生物电Fenton系统,为印染废水脱色提供了崭新的途径。     

曝气条件下微电解-Fenton工艺联合处理模拟染料废水的研究

曝气条件下采用微电解-Fenton工艺处理模拟染料废水。在最佳微电解工艺即铁炭比为45 g∶45 g,pH=3,反应时间为60 min;在Fenton工艺pH值为3,H2O2投加量0.7 mL,反应时间为120 min时,染料废水总脱色率达92%,其色度去除率高于单独微电解工艺时的63%和单独Fenton工艺时的67%。模拟染料废水经微电解及Fenton工艺处理后,废水pH值、Fe2+浓度和色度均发生变化。     

酸性染料的臭氧降解与中间产物

以酸性金黄G模拟染料废水为研究对象,观察臭氧氧化过程中染料溶液吸光度和TOC的变化,利用离子色谱仪、红外光谱仪和GC/MS对染料的降解过程进行了分析,并用发光细菌法检测了溶液急性毒性的变化,结果表明,臭氧对染料的降解符合一级反应动力学,反应40 min后染料溶液的脱色率达到99.3%,TOC去除率为35.7%;染料分子中的S有97.8%被转化为SO2-4,分子中的仲胺基部分转化成酰胺基,水解后生成NH+4,最终氧化成NO-3,溶液中有草酸产生;溶液在臭氧化前期由于生成了醛类和酚类物质,使急性毒性首先呈上升趋势,25min后随着氧化的深入,溶液毒性开始逐渐下降,     

高浓度聚合氯化铁混凝剂的净水效果

采用共聚方法制备聚合氯化铁混凝剂．试验了它对模拟水的除浊和脱色效果,对高、中、低浊度的地表水以及炼油废水的处理效果．实验结果表明：与FeCl3相比,聚合氯化铁(PFC)具有更好的除浊、脱色效果,COD去除率、除油率的效果大大提高;W／Fe摩尔比对PFC混凝效果的影响不尽相同,在实际水处理中,应根据处理对象的不同,选择合适的参数以达到最佳的混凝效果．     

脉冲电晕放电对印染废水脱色效果的实验研究

用高压毫微秒脉冲产生直接与废水接触的非平衡等离子体,能使屯染废水在处理数１０秒内脱除颜色。对模拟印染废水的实验研究表明,当脉冲峰值电压达３８ｋＶ时,脱 不受试样ＰＨ值影响,在处理４０ｓ后,脱色率达９５％以上,当脉冲峰值电压较低时,脱色率与试样ＰＨ值有关,中性试样的脱色率较低,处理４０ｓ后脱色率在４０－５０％,而当ＰＨ〈４或ＰＨ〉７时,处理４０ｓ后脱色率最高也可达８０％以上。试样中加入ＮａＣｌ和Ｎａ     

一株红假单胞菌对偶氮染料的脱色研究

一株球形红假单胞菌(Rhodobacter sphaeroides YB)缺氧情况下对数种偶氮染料的24 h脱色率达到90％以上。结构相对简单的偶氮染料较容易脱色。研究了外加碳源、温度和pH值等环境因素对该菌生长以及脱色活性的影响,得出最优脱色条件为:光照缺氧、蛋白胨作碳源、温度35～40℃、pH=7-8。     

脱色菌腐败希瓦氏菌的分离及其脱色性能研究

从印染废水处理装置中分离到一株高效脱色菌,经鉴定为腐败希瓦氏菌(Shewanella putrefaciens),这是该菌具有高效脱色性能的首次报道。在实验条件下,对该菌的脱色能力进行比较研究,它在合适条件下能有效地去除生产上常用的多种染料,在6h内对活性艳红染料的去除率可达99％～100％。实验中对充氧、温度以及共代谢碳源等因子对该苗的脱色能力的影响进行了研究,为在生产实际中的应用提供了依据。