Study on Preparation of Rabbit Manure Biochar and Activation of Peroxymonosulfate for Rhodamine B Degradation

Using rabbit manure as raw material, three distinct types of rabbit manure biochar (RBC400, RBC500, and RBC600) were prepared via pyrolysis at 400 degrees C, 500 degrees C, and 600 degrees C, respectively. The effects of pyrolysis temperature on the physicochemical properties of biochar were examined by scanning electron microscopy, Brunauer-Emmett-Teller analysis, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction techniques. Rabbit manure biochar was used to activate permonosulfate (PMS) to degrade rhodamine B (RhB). The findings revealed that RBC600 prepared at 600 degrees C showed the strongest catalytic activity due to its abundant pores and pore structure, high graphitization, and high carbonization degree. Under optimal reaction conditions (0.4 g/L PMS and 0.6 g/L RBC600), the degradation rate of 50 mg/L RhB reached 93.38% within 60 min. RBC600 can be effectively recovered, and effective catalytic activity can be sustained after five cycles. The quenching and EPR experiments showed that both free-radical (SO4- and center dot OH) and non-free-radical (O-1(2)) pathways contributed to the degradation of RhB, in which O-1(2) performed a dominant role. In conclusion, the new PMS activator prepared in this study not only realizes the "waste to waste" use of manure waste but also provides technical support for the efficient resource-based treatment of organic wastewater.