Combined ozone oxidation process and adsorption methods for the removal of acetaminophen and amoxicillin from aqueous solution; kinetic and optimisation

Abstract

Abstract The growing use of pharmaceuticals raises questions on their potential risk to human health and water quality. This research aimed to introduce a combined treatment technique with high performance in removing pharmaceutical micropollutants (MPs) from aqueous solution. The research included two steps, ozone treatment (first step) and adsorption technique (second step). The elimination of acetaminophen (ACT) and amoxicillin (AMX) with ozone reactor, first step, was optimised by artificial neural network (ANN). The optimisation process included two independent variables, namely, initial concentration of MPs and ozone dosage. On the basis of ANN, the linear regression coefficient denoted by R2 between predicted and experimental MP removals was close to 1. Result displayed that the prediction by the trained ANN is acceptable. Approximately 0.17 mg/L (84.8%) of ACT and 0.16 mg/L (82.7%) of AMX were removed at the initial concentration of 0.2 mg/L and ozone dosage of 15 mg/L. Beside it, ozonation experiments showed that the rate of constant (m − 1 s − 1 ) for ACT and AMX were 2.63 × 106 and 5.98 × 106 respectively. After treating by ozone reactor, water was subjected to pass through the cross-linked chitosan/bentonite as a fixed-bed column, for second step. ACT and AMX were not detected after step 2.