Sorption of Cu(II) Ions from Aqueous Solution with Synthesized B-Doped Heptazine-Based g-C/N/H Polymers

In this study, boron doped heptazine-based g-C/N/H polymers (B-doped heptazine-based g-C/N/H polymers) were synthesized by the pyrolysis process of the mixture of low cost H₃BO₃ and melamine. X-ray power diffractometer (XRD) and Fourier transform infrared spectroscopy (FT-IR) were applied to characterize the successful doping of B atoms into the nanostructure of the graphic-C₃N₄ (heptazine-based g-C/N/H polymers). The synthesized material was conducted to investigate the sorption capacity for Cu(II) ions from aqueous solution and the sorption conditions including the doped amount, the solution pH, the contact time, and initial concentration were optimized. The results indicated that the sorption process was dependent on solution pH and the optimum pH was from 3.0 to 6.0. The kinetics was well evaluated by pseudo-second-order which indicated that the main rate-determining step was controlled by the chemical sorption process. The maximum sorption capacity calculated from Langmuir model amounted to 149.3 mg g^?1 with the initial concentration range from 80 ～ 800 mg L^?1. So, B-doped heptazine-based g-C/N/H polymers have the potential application as a low cost adsorbent for high concentration Cu(II) ions in aqueous solution.