Reusable biochars derived from Camellia oleifera shell via K2CO3 activated for phenol-enhanced adsorption

Porous biochar materials (BC) have shown excellent performance in energy storage and water treatment adsorption. Carbonization of agricultural and forestry solid waste and fixation in the form of stable biochar to form biochar materials can achieve green "waste utilization for treatment wastewater". In this study, BC samples were generated by using Camellia oleifera shell (COS) as raw material and K2CO3 as green activator in-situ pyrolysis. The adsorption behavior of COS biochar in aqueous solution was evaluated using phenol as a pollutant probe. The synergistic effect of pyrolysis temperature and K2CO3 activation promoted the development of the pore structure of BC. The X-ray photoelectron spectroscopy results indicated that K2CO3 activation promoted the formation of C-C defects and promoted phenol adsorption. KBC-900 exhibited superior absorption capacity for phenol (300.15 mg/g). The activation of K2CO3 also promoted the adsorption of oxygen. In addition, using H2O2 for regenerating biochar did not show a significant decrease in the adsorption rate after five cycles (decline rate < 5 %). The strong adsorption capacity of KBC-900 for phenol might be due to the presence of π-π interactions, hydrogen bonds, and van der Waals interactions during the adsorption process. •100 % adsorption rate of phenol in aqueous solution (300.15 mg/g).•BC itself has a high adsorption rate, higher and more stable after activation.•The introduction of H2O2 achieved complete degradation of phenol.•Realizing Resource Reuse of Solid Waste.