فهرست نشریات علمی دسترسی آزاد ایران

The Dyeing and textile industries are among the sectors that hold a significant global presence in Iran and worldwide. These industries are major water consumers; consequently, substantial quantities of wastewater containing toxic compounds, including synthetic dyes, are released into the environment at various stages of the process within these industries. The treatment and purification of wastewater generated by these industries is of great importance to reduce their associated risks, and a range of physical, chemical, and biological methods are employed to remove pollutants from industrial wastewater. Meanwhile, the use of microalgae for bioremediation is one of the primary eco-friendly treatment methods due to its low cost, reliance on natural processes, and reduced risk of toxic substance accumulation. In this study, the microalgae Tetradesmus obliquus were utilized to investigate the removal rate of Acid Blue 92 dye under various environmental conditions, including temperature, pH, and initial concentration of the dye, initial cell number, and reaction duration. The treatments encompassed temperature (25, 10, 5 ºС), pH (8.5, 7.5, 6.5, 5.5, 4.5), initial dye concentration (5, 10, 20, and 50 mg/L), initial cell number (5, 10, 20, and 30 ×106 cells. mL-1), and reaction duration (every 24 hours for 4 days). Furthermore, the reusability of individual algal biomass in the continuous purification of the dyes was investigated through several consecutive decolorization experiments. Based on the results, the removal efficiency of Acid Blue 92 dye increased with increasing cell number and increasing temperature. However, the removal efficiency decreased with increasing initial concentration of the dye. In addition, the optimal pH for the dye decolorization process was determined to be in the pH range of 6-7. The results of the pollutant removal reproducibility tests showed that this alga can repeatedly remove the dye from the contaminated wastewater. Therefore, the algae probably absorb and degrade the pollutant from the environment to an acceptable extent by utilizing the biodegradation process. In conclusion, it can be stated that T. obliquus algae have a significant capacity for the removal and biotreatment of acid blue dye 92, particularly under optimal conditions, and may be considered as a viable option for eliminating colored pollutants in aquatic environments.