Construction of a physically cross-linked carrageenan/chitosan/potassium phytate double-network hydrogel for dihydroxylammonium 5, 5′ -bistetrazole-1, 1′ -diolate (TKX-50) removal and recovery

TKX-50 is a new high energy and low sensitivity energetic ionic salt with great application potentials. However, the separation and removal of TKX-50 from the wastewater generated during its preparation and application are usually difficult. In the present work, we successfully prepared a carrageenan/chitosan/potassium phytate physically cross-linked double network hydrogel (KC/CTS/PAP PCDNH) by the semi-dissolution/acidification/sol-gel transition (SD-A-SGT) method. The structure and TKX-50 adsorption performance of the hydrogel were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The adsorption kinetics, isotherm, and thermodynamics were then investigated. The effects of organic solvents on TKX-50 adsorption were evaluated. The TKX-50 adsorbed in hydrogel was successfully recovered with a NaOH solution. In all, the hydrogel shows great application potentials for the TKX-50 wastewater treatment as a green adsorbent.