Bifunctional two-dimensional copper-aluminum modified filter paper composite for efficient tetracycline removal: Synergy of adsorption and reusability by degradation.

Herein, bifunctional two-dimensional copper-aluminum modified filter paper composite (2D-Cu/Al-C) was successfully prepared by simple calcination and showed ultrahigh adsorption performance and degradation potential. The adsorption removal of TC on 2D-Cu/Al-C all exceeded 92.2% under solution conditions of 10-200 mg/L TC, 100 mg/L 2D-Cu/Al-C, pH 8 and 298 K. The pseudo-second-order kinetic and Langmuir models better fitted the kinetic and isotherm data via spontaneous and exothermic process, and the maximum capacity of the 2D-Cu/Al-C was 2391.78 mg/g. Additionally, 2D-Cu/Al-C showed desired specific adsorption for TC (TC: 98.7%, norfloxacin: 5.8%, sulfamethoxazole: 2.1%, and ciprofloxacin: 1.8%) and it could effectively adsorbed TC even in the binary system (various coexisting ions or natural organic matter). After TC adsorbed on adsorbent was mineralized into CO and HO by adding peroxydisulfate to generate high electrode potential radical in another limited systems, the 2D-Cu/Al-C still had ∼89.12% on TC removal (initial concentration of 50 mg/L) after five experimental cycles. Zeta potential, FT-IR and XPS results indicated that the multi-adsorption mechanism, including electrostatic interactions, complexation, and H-bonds, played a vital role in the fast and efficient adsorption process. Thus, the way of combining adsorption and regeneration via degradation are green, non-polluting strategy which are expected to be applied for water purification in future environmental remediation.