Spirulina, wastewater dye absorbent microalgae

Dye is the first known pollutant in industrial wastewater, and its small amount is very undesirable in water. Most of the dyes contain complex organic molecules and are harmful to aquatic life and humans due to the presence of metals, aromatics and other compounds in their structure. Removing or reducing the amount of this pollutant entering the environment is essential, and biological absorption is one of these methods. The main purpose of this research is to investigate the removal of blue reactive textile dye by spirulina microalgae. In the process of conducting the research, the effect of variables such as contact time, injected algae dose and wastewater concentration was investigated on the dye removal process and the amount of absorption of the samples was measured by a spectrophotometer and the number of experiments was determined by the design expert software via response surface method (RSM) and the analysis of variance (ANOVA) statistical tool was used to analyze the obtained results. Based on the obtained results, in the optimal conditions of the experiment, the best percentage of dye removal by spirulina microalgae was 100% in contact time of 30 minutes with a dose of 10 ml of injected algae into wastewater with a color concentration of 50 mg/L. Therefore, the use of microalgae, in addition to being an inexpensive and easy-to-operate method for color removal from colored wastewater such as textile wastewater, it will be of interest to researchers as an environmentally friendly method to remove hard degradable pollutants.