Abstract

Natural organic matters (NOMs) are present in many water resources across the world, particularly surface and groundwater sources. NOMs in water supplies cause several issues, particularly in the conventional water treatment procedure. One of the most important precursors of water disinfection by-products is the existence of contaminants such as acid humic (HA) in water. This study aimed to investigate the simultaneous function of hydrogen peroxide (H2O2) and ultrasonic in the removal of HA from aqueous solutions. In the presence of H2O2 and ultrasonic, the influence of affective factors such as pH (3-9), contact time (5-30 min), HA concentration (10-50 mg/L), and H2O2 (mM) concentration was evaluated discontinuously on HA removal effectiveness. A spectrophotometer set to 254 nm was used to determine the final HA concentration. As a result, H2O2 concentration was directly related to HA removal effectiveness, whereas HA concentration was inversely related. Under optimal ultrasonic time of 5 min, the maximum removal effectiveness of HA (50) was 10 mg/L = HA, H2O2 = 0.10 mM. Also, this degradation process followed pseudo-first-order kinetic (R2 > 0.9). The removal rate by ultrasonic and H2O2 was acceptable, indicating that the combined use of H2O2 and ultrasonic in the generation of hydroxyl radicals is successful. As a consequence, ultrasonic and H2O2 pre-treatment of HA-containing water may be a reasonable solution.