Activated Carbon in Biodecolorization of Azo Dye Methyl Red by Klebsiella quasipneumoniae GT7
کد مقاله : 1208-IWWA
نویسندگان
طیبه باقری لطف آباد *1، پدرام حسنوند2، مسعود رجبی3، پروین شریعتی1، سهیلا یغمایی4
1پژوهشکده زیست فناوری صنعت و محیط زیست، پژوهشگاه ملی مهندسی ژنتیک و زیست فناوری.
2پژوهشکده زیست فناوری صنعت و محیط زیست، پژوهشگاه ملی مهندسی ژنتیک و زیست فناوری
3دانشکده مهندسی شیمی و نفت، دانشگاه صنعتی شریف .
4دانشکده مهندسی شیمی و نفت. دانشگاه صنعتی شریف.
چکیده مقاله
Industrial wastewater containing azo dyes poses a significant threat to natural water bodies, human health, and the environment. Despite the advantages of anaerobic methods for removing these pollutants, their industrial adoption is limited due to their time-consuming nature. This study assesses the effectiveness of activated carbon (AC) in accelerating the anaerobic reduction of the azo dye methyl red by Klebsiella quasipneumoniae GT7. Decolorization experiments were conducted at 30°C with initial dye concentrations of 0.1-6 mM. Each experiment included three sets: inoculated medium with 0.5% AC, inoculated medium without AC, and non-inoculated medium with 0.5% AC. Samples were collected at specific time intervals, centrifuged, and the supernatant analyzed for residual dye using a spectrophotometer and thin-layer chromatography (TLC). In the non-inoculated medium, 0.5% AC achieved complete decolorization within minutes for dye concentrations below 2 mM. At higher concentrations, efficiency decreased to 95%-62% over 24 hours. The efficiency of dye adsorption was influenced by the maximum adsorption capacity of AC, as estimated by the Langmuir isotherm model (qmax ≃ 227.27 mg/g). In the inoculated medium without AC, complete decolorization occurred within less than 4 hours. In the inoculated medium with AC, complete decolorization was achieved within 6-10 hours. TLC showed that in the presence of bacteria, with or without AC, the dye was reduced into aromatic amines, manifesting as fluorescent spots. Incorporating 0.5% AC during bacterial decolorization significantly enhanced the rate of dye reduction.
کلیدواژه ها
Activated carbon, Azo dye, Klebsiella quasipneumoniae
وضعیت: پذیرفته شده برای ارائه شفاهی