Removal of reactive dyes by using microalgae; reactive red (120) and reactive blue (198)

Toxic dyes constitute the largest part of textile wastes. In addition, these substances are soluble substances and may be present in large amounts in wastewater. In this research, Chlorella vulgaris is used for the biosorption of two most used textile dyes Reactive Red 120 and Reactive Blue 198. Main goal is identifying optimum conditions for biosorption of these dyes on to dry microalgae with using spectrophotometer. For this purpose, adsorption studies were conducted under different temperatures, different pH, initial dye concentrations and contact time. Optimum pH for C. vulgaris is found 2. The optimum biosorbent amount is 0.05 g. Then, initial dye contentration, optimum contact duration and temperature is examined. These results are respectively, 100 mg/ L, 30 minutes and 25 °C. When the optimum factors maintained, overall removal percentage is near %95 for Reactive Red 120. For Reactive Blue 198, the studies show that the adsorption on the C. vulgaris is best under pH=2, 25 °C. The adsorption on to C. vulgaris was completed in 30 minute. The optimum biosorbent was found as 0.05 g. The studies show that the removal rate for Reactive Blue was about %94 under these conditions when the 100 mg/L initial dye concentration was used.