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采用混凝沉淀-Fenton催化氧化组合工艺对蒽醌染整废水进行处理,研究了混凝剂和Fenton试剂投加量以及各种反应条件对处理效果的影响。试验结果表明,当pH值为6.2、A12(SO4)3投量为300mg/L、PAM投量为3mg/L、沉淀时间为30min时,混凝沉淀出水的COD为233~260mg/L,色度为15~20倍;后续处理采用Fenton试剂催化氧化,当FeSO4投量为200mg/L、H2O2投量为100mg/L、pH值为5.0、反应时间为30min时,出水色度≤10倍,BOD5≤10mg/L,COD≤50mg/L。 相似文献
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Decolorization and toxicity of reactive anthraquinone textile dyes under methanogenic conditions 总被引:8,自引:0,他引:8
Reductive decolorization of two anthraquinone reactive dyes (Reactive Blue 4, RB4; Reactive Blue 19, RB19) under methanogenic conditions was performed using a mixed, methanogenic culture. Decolorization of the two anthraquinone dyes was investigated to evaluate the rate and extent of color removal as well as to assess possible toxic effects of the dyes and their decolorization product(s) on the methanogenic culture as a function of initial dye concentration ranging from 50 to 300 mg x L(-1). A dextrin/peptone mixture was used as the carbon and electron source. A high rate and extent of color removal was achieved ranging from 4.3 to 29.9 mg x L(-1)h(-1) and 73-91% for RB4, and 13.0-74.4 mg x L(-1)h(-1) and 90-95% for RB19. Initial RB4 concentrations up to 100 mg x L(-1) did not result in any significant inhibition. Both the 200 and 300 mg x L(-1) RB4-amended cultures, and all RB19-amended cultures resulted in severe inhibition of both acidogenesis and methanogenesis. Sequential dye addition at 300 mg x L(-1) for both RB4 and RB19 resulted in accumulation of volatile fatty acids (VFAs) and a very low methane production at the end of the first dye addition after 44 days of incubation. However, at the end of the second dye addition, after a relatively long incubation (384 days), recovery of methanogens in the RB4-amended culture was observed in contrast to the complete inhibition of methanogenesis in the RB19-amended culture. Therefore, RB19 resulted in a higher degree of inhibition of both acidogenesis and methanogenesis than RB4. Addition of dextrin/peptone to dye-inhibited cultures resulted in acidogenesis and a gradual recovery of methanogenesis (mainly aceticlastic methanogenesis) in the RB4-inhibited culture, and a slow recovery of acidogenesis but no recovery of methanogenesis in the RB19-inhibited culture. In contrast, addition of 80% H(2)-20% CO(2) gas to dye-inhibited cultures resulted in recovery of hydrogenotrophic methanogenesis in both the RB4- and RB19-inhibited cultures. In spite of the relatively severe inhibition of the two anthraquinone dyes on the mixed, methanogenic culture, a high extent of color removal was achieved. 相似文献
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Kim Bini Desta Gedefaw Caroline Pan Jonas M. Bjuggren Anirudh Sharma Ergang Wang Mats R. Andersson 《应用聚合物科学杂志》2019,136(27):47729
An easily accessible anthraquinone-benzodithiophene-based high bandgap polymer (PTAq) was synthesized by Stille coupling reactions in remarkably high yield (96.5%). The highest occupied molecular orbital energy level of the polymer was estimated from the onset of oxidation in a cyclic voltammetry study to be −5.7 eV. PTAq showed an orange-to-green color switching with the application of a 1.0-V external potential to the polymer film, which was visible to the naked eye. The optical behavior change was also monitored using ultraviolet–visible absorption spectroscopy and revealed a respectable 75% transmittance change when the polymer film was subjected to a 1.0-V external potential. The high color contrast observed makes PTAq one of the most promising materials for electrochromic device applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47729. 相似文献
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采用等体积浸渍法制备了负载型磷钨酸(HPW)催化剂,将其用于催化邻苯甲酰苯甲酸(BBA)脱水合成蒽醌;采用XRD,FTIR,TG-DTG等手段对SiO_2负载的磷钨酸(HPW/SiO_2)催化剂进行表征;考察了载体种类、焙烧温度、HPW负载量对其催化性能的影响。实验结果表明,制备负载型HPW催化剂的适宜条件为:以SiO_2为载体、焙烧温度250℃、焙烧时间3 h、HPW负载量为30%。HPW/SiO_2催化剂催化合成蒽醌的适宜反应条件为:催化剂与BBA的质量比为1.60、反应温度220℃、反应时间2.0 h,在此条件下,蒽醌收率可达99.6%。HPW/SiO_2催化剂的稳定性较差,BET,UV-Vis,Py-IR表征结果显示,积碳结焦使催化剂B酸酸量减小是催化剂失活的原因。 相似文献
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于剑昆 《化学推进剂与高分子材料》2011,9(4):9-15
详细介绍了在不同催化剂存在下使2-甲基环己醇与乙酸或乙酸酐反应合成醋酸甲基环己酯(2-MCA)的工艺.在蒽醌法工作液中用2-MCA代替磷酸三辛酯作溶剂,可增加蒽醌和蒽氢醌在工作液中的溶解度以及过氧化氢的分配系数,提高氢化效率和过氧化氢在工作液中的浓度,从而有利于提高过氧化氢装置产能和降低操作费用.此外,还给出了几个国内... 相似文献
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A novel anthraquinone‐containing bis(ether amine) monomer, 2,6‐bis(4‐aminophenoxy)anthraquinone, was synthesized from readily available reagents. A series of novel aromatic polyimides were prepared from the newly synthesized diamine monomer with various aromatic tetracarboxylic dianhydrides. The intermediate poly(amic acid)s had inherent viscosities of 0.67–1.12 dL g?1, and those derived from less stiff dianhydrides could be solution‐cast and thermally cyclodehydrated into flexible and tough polyimide films. The polyimides exhibited glass transition temperatures between 270 and 297 °C, and they were fairly stable up to a temperature of 500 °C in air or nitrogen. The electrochemical and electrochromic properties of one of the polyimides were investigated. The polymer could undergo two reversible steps of electrochemical reduction, with a color change from a colorless neutral state to pink and rose‐red reduced states. © 2012 Society of Chemical Industry 相似文献