Magnetic porous biochar with nanostructure surface derived from penicillin fermentation dregs pyrolysis with KFeO activation: Characterization and application in penicillin adsorption.

Magnetic porous biochars (MC, MC) with nanostructure on surfaces were prepared from penicillin fermentation dregs by pyrolysis with KFeO activation and used in penicillin adsorption. MC and MC had high BET surface areas of 672 and 735 m/g, respectively; mainly be attributed to the activation of KFeO as well as acid pickling. Saturation magnetizations of MC and MC were 75.29 and 42.45 emu/g, respectively; the magnetism was mainly derived from the FeO and FeC in magnetic biochars. MC had nano sticks of ~ 80 nm and MC had petal-like slice of ~ 30 nm on surfaces. The maximum adsorption capacities of penicillin on MC and MC were 196 and 322 mg/g at 308 K, respectively. The adsorptions of penicillin on MC and MC were consistent with pseudo primary kinetics and the Langmuir adsorption isotherm model, and thermodynamic analysis indicated that the adsorption mechanism included physical and chemical adsorption.