Preparation of Reed Biochar and Study on Its Phosphorus Adsorption Characteristics

Excessive nutrient phosphorus in water can cause eutrophication, affecting ecosystems, human health, and socioeconomics. Using plants to prepare biochar can not only effectively adsorb phosphate in water, but also realize the utilization of waste resources. In this paper, reed biochar was prepared to explore its physical characteristics and phosphorus adsorption characteristics. The results are as follows: (1) the surface of reed biochar is distributed with a large number of irregular granular protrusions, with large specific surface area, many pores, and functional group such as hydroxyl groups; (2) phosphorus adsorption experiments with different variables were set up, and the optimum addition amount and pH for phosphorus removal by reed biochar were obtained; (3) the kinetic fitting data showed that the pseudo-second-order kinetic model could better describe the reed biochar; and (4) the adsorption isotherm data showed that the adsorption process conforms to the Langmuir and Freundlich isotherm adsorption models at the same time.