Nitrogen doped graphitic porous carbon from Almond Shell as an efficient persulfate activator for organic compounds degradation
Here, we have developed a simple and efficient low-temperature process for doping N into graphitic porous carbon to prepare a catalyst: N-GPC. Almond Shell (AS) as Bio-sourced material was used for graphitic porous carbon preparation via a new facile environmentally approach followed by pyrolysis. The resulted powder was characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier-Transform Infrared Spectroscopy, Scanning Electron Microscope, Raman Spectroscopy and BET. The catalytic activity was investigated by using Orange-G (OG) as the target pollutant and N-GPC as heterogeneous catalyst to activate persulfate (PS). The influence of various parameters such as temperature, PS concentration, catalyst dose, pH and time over the N-GPC/PS system was investigated. OG discoloration of 99% was achieved with a degradation rate of 70% using [N-GPC] = 0.2 g/L, [OG] = 100 mg/L mM, [PS] = 4 mM at ambient temperature and natural pH. The catalyst N-GPC could be recycled easily for three cycles with a good stability. Moreover, quenching experiments and EPR analysis were investigated to elucidate the active radicals participating in the degradation process. The results indicated that 1O2 is the most dominant non-radical species in the degradation process of OG. The enhanced activities of N-GPC/PS system were attributed to the high surface area and generated charges from the surface of the prepared N-GPC. This strategy can lead to sufficiently manage biomass waste to pave the way to environmentally friendly catalysis.