[Removal of acid black 1 dye by carbon nanotube-dendrimer composite: operation parameters, isotherms and kinetic]

Organic dyes are the major pollutants produced in many industries and have different adverse effects on water resources. The aim of this study was to synthesize a novel adsorbent with high adsorption capacity and evaluate its efficiency in removing organic dyes from aqueous solutions in a batch system. This study was an applied research in which carbon nanotube composite-dendrimer was synthesized and its chemical properties was evaluated by fourier transform infrared spectroscopy. Acid blue 1 dye was selected as a model to evaluate the decolorization capacity of the adsorbent. The effects of the parameters influencing the adsorption process such as initial dye concentration, adsorbent dose, pH and the effect of inorganic salts were also studied. Longmuir and Freundlich isotherm models and pseudo first order and pseudo-second-order kinetic models were used for data evaluation. In this study removal of acid black 1 dye by carbon nanotube-dendrimer composite followed the Longmuir and Freundlich isotherm and pseudo-second-order kinetic models. We also found that the synthesized adsorbent had a maximum adsorbent capacity equal to 690 mg/g, when the concentration of dye was 100 mg/l. We concluded that carbon nanotube composites - dendrimer can be used as an effective adsorbent for removal of dyes form colored effluents

[Assessment of SBR system performance in the removal of reactive yellow3 dye from synthetic wastewater]

Millions of liters of color effluents are produced by textile industries and plants. Every liter of effluents may contain more than 20gr of pigments and mediators produced by their degradation which can result in environmental problems. Chemical dyes used in textile industries have some potential risks including carcinogenic and mutagenic effects on human. Further, these dyes can penetrate into surface and ground water. The aim of this study was to investigate the efficiency of combined CAC-SBR system for removal of Reactive yellow 3 dyes. This experimental study was conducted based on a batch scale, and two SBR reactors were used for the experiment. We used synthetic wastewater samples in this study [COD=1800]. After adjusting the reactors, reactive yellow3 dye was injected into the system and its removal efficiency was investigated during different reaction times. Then SBR system efficiency in dye and COD removal was determined. After 24 hours of reaction, the efficiency of SBR system in the removal of reactive yellow3 dye was 58%. But the efficiency of SBR system in COD removal was 98% after 14 hours of reaction. In this study, by increasing the reaction time SBR efficiency increased and stabilized in a distinct time. SBR efficiency in the removal of dye and COD, together with high efficiency of anaerobic system in dye removal reveals that a combination of aerobic and anaerobic systems can be suitable for synchronic dye and COD removal.