The study of removing trimethoprim by simulating the Chaobai River basin with artificial composite soil treatment system

Based on the reclaimed water recharge of Chaobai River, clay ceramsites were chosen as adsorbent in this study, which has the character of low price and high adsorption capacity of trimethoprim (TMP), in order to reduce the amount of TMP entering into environment. The adsorption capacity of TMP reached 151.824 μg/g, which has the ability of removing TMP from reclaimed water. Desorption experimental results showed that the desorption hysteresis of TMP in clay ceramsites was delayed. We systematically investigated the removal of TMP by an artificial composite soil treatment system. The results showed that the artificial composite soil system could effectively remove TMP and the remove rate was higher than 95%. The combination of adsorption effect and biodegradation is the TMP major removal mechanism. This artificial composite soil treatment system can effectively remove TMP from the reclaimed water, and it has a guiding role in the field recharge.