Preparation of biomass artificial humic acid/hydrothermal carbon composite and its high-efficiency adsorption of norfloxacin

In this study, artificial humic acid (AHA) and hydrothermal carbon (HC) were prepared from Biomass materials corn straw. With HC as matrix, AHA/HC composites with high-efficiency adsorption performance for norfloxacin (NOR) were prepared by coprecipitation method according to the mass ratio of mAHA:mHC = 1:4, which was green and environmentally friendly in preparation, regeneration and pollutant treatment. The oxygen content of AHA/HC was obviously increased by ultrasonic-assisted acid-alkaline combined hydrothermal method, its saturated adsorption capacity for NOR was 565.48 mg/g, which was higher than that of other reported adsorption materials, the high-efficiency adsorption is due to the fact that HC is combined by AHA rich in oxygen-containing groups (-OH, -C=O, etc.). Meanwhile, the problem that AHA was dissolved in alkaline condition is solved. It had good selective adsorption for NOR, with less interference from acidity of environmental water, coexisting inorganic ions and antibiotics with high detection rates. After five times of reuse, the adsorption capacity of the AHA/HC was still over 90 %. The adsorption mechanism was π-π stacking, hydrogen bonding and electrostatic bonding. The removal rate of NOR in simulated water with concentration of 10.0 mg/L prepared from different environmental waters was 91–95 %, and the concentration is 16 times of the highest concentration of 630 μg/L in polluted water. It showed that AHA/HC can not only remove all NOR in environmental water, but also its adsorption capacity far exceeds the pollution amount. The research has important practical significance in realizing the recycling of agricultural wastes and the removal of environmental pollution. [Display omitted] •AHA and HC were prepared from Corn straw concurrently and compounded into AHA/HC.•The adsorption capacity of AHA/HC for NOR is 565.48 mg/g with high efficiency.•AHA/HC has good recycling and regeneration properties.•AHA/HC was green and environmentally friendly in preparation, regeneration and pollutant treatment.•Comprehensive utilization of waste biomass is further realized.