Introduction: The presence of antibiotics due to toxicity and sustainability as well as organic compounds as a combination of hard biodegradable wastewater is an undesirable issue in many industries. The aim of this study was to evaluate the efficiency of dissolved air flotation process for aniline and penicillin G removal from aqueous solutions.

Methods: This was an empirical-lab study to which the dissolved air flotation method was applied in laboratory scale. The effects of effective parameters including concentration of coagulant poly-aluminum chloride (PAC) (10, 20, 30, 40, 60 mg/L), coagulation time (5, 10, 15 and 20 minutes), flotation time (5, 10, 15 and 20 seconds) and saturation pressure (3, 3.5, 4 and 4, 5 atm) on the removal efficiency of aniline and penicillin G by dissolve air flotation were studied.

Results: The results showed that dissolved air flotation method can reduce penicillin G and aniline up to 67.45% and 95%, respectively. The optimum condition was as follows: pH = 6, initial concentration of aniline = 200 mg/L, initial concentration of penicillin G = 25 mg/L, coagulation time = 10 minutes, flotation time = 10 seconds, pressure = 4 atm, and PAC concentration = 20 mg/L.

Conclusions: Dissolved air flotation process can be an effective method to remove aniline and penicillin G from aqueous solutions.