Biomass waste-derived porous carbon efficient for simultaneous removal of chlortetracycline and hexavalent chromium

The simultaneous removal of mixed containments of antibiotics and heavy metals is still a big challenge in wastewater treatment. Herein, we report the successful synthesis of N-doped porous carbon (abbreviated as NC) from straw waste through the Maillard reaction to activate sp(3)-sp(2) conversion efficient for the simultaneous removal of chlortetracycline (CTC) and hexavalent chromium (Cr(VI)). In 200 min, 96.9% of Cr(VI) was reduced into Cr(III) and 93.1% of CTC was oxidatively degraded. Reactive substances (e.g., h(+), e(−1), ⋅OH, and ⋅O(2)(-)) were verified for the photocatalytic reactions. Besides, the possible degradation intermediates of CTC were analyzed with ultra performance liquid chromatography-mass spectrometry (UPLC-MS/MS), and the mechanism of photocatalytic degradation of CTC was then proposed. The synthesized bifunctional NC materials could also be applied for the similar system; this will open the door for promising practical applications.