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 K 2 CO 3 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 K 2 CO 3 activation promoted the development of the pore structure of BC. The X-ray photoelectron spectroscopy results indicated that K 2 CO 3 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 K 2 CO 3 also promoted the adsorption of oxygen. In addition, using H 2 O 2 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 .