Abstract

Reactive dyes have carcinogenic potential due to the presence of benzene rings. Therefore, in order to avoid health and environmental hazards, dyes of the wastewater must be removed before discharging to the environment. This study aimed to evaluate the effectiveness of Plantago major seed extract as a natural coagulant in removal of Reactive Blue 19 dye from industrial wastewater. In this experimental study, the effects of different factors, including pH (5-11), coagulant dose (0.02-2 g/L), dye concentration (10-100 mg/L), settling time (15-90 min), and temperature (26-76 degrees C), were tested. The results showed that pH, coagulation dose, initial concentration of dye, settling time, and optimal degrees of temperature were, respectively, 9, 1.2 g/L, 40 mg/L, 60 min, and 56 degrees C for removal of Reactive Blue 19 dye using the extract of Plantago major seed. In these conditions, the highest removal efficiency was 35, 54.5, 60.66, 64, and 69 respectively. In the conditions that all parameters were in optimal mode, the removal rate was about 70. Based on the results of this study, although the removal rate of Reactive Blue 19 dye by Plantago major seed extract, even in optimal conditions, was lower than advanced oxidation methods, this material can be used as a natural coagulant to remove this dye from aqueous solutions and industrial wastewater. In addition, in order to increase the efficiency of this substance, further studies to upgrade and optimize these parameters is essential.