Degradation of tetracycline by FeNi-LDH/TiC photo-Fenton system in water: From performance to mechanism.

Recently, photo-Fenton technology has been widely used to degrade tetracycline (TC) because of its great efficiency and wide application range. Herein, Fe-Ni layered double hydroxides (FeNi-LDH)/TiC photo-Fenton system was constructed in this study. The results showed the introduction of TiC solved some problems of FeNi-LDH such as poor conductivity, easy aggregation, and high recombination rate of photoelectron. Benefiting from these advantages, FeNi-LDH/TiC exhibited excellent TC removal rate of 94.7% while pure FeNi-LDH was only 54%. Besides, FeNi-LDH/TiC possessed strong pH tolerance (2-11) and the removal efficiency was still up to 82% after the four-cycle experiment. Furthermore, the quenching experiments revealed the reaction mechanism, where ∙OH and ·O were the primary active radicals for degrading TC. Last, the results of the simulated wastewater treatment and the inorganic ion interference tests showed that FeNi-LDH/TiC possessed practical application potential. In brief, this study shows that FeNi-LDH/TiC can offer a certain theoretical basis for the actual development of hydrotalcite in heterogeneous photo-Fenton systems.