Biochar with enhanced performance prepared based on “Soil microbiota pretreatment” designed for efficient removal of antibiotics

The increasing demand for the resource utilization of agricultural waste has made the development of efficient conversion technologies for corn straw-a typical biomass resource-a focal point of research. Meanwhile, the escalating threat of antibiotic contamination to aquatic environments underscores the critical need for novel and efficient adsorbent materials with significant environmental relevance. In this study, corn straw (CS) was pretreated using an embedding method with soil microbial flora. The changes in lignocellulosic components and related structures in the straw were analyzed, and the status of the associated bacterial and fungal communities was dynamically monitored. Subsequently, the pretreated CS was converted into biochar through carbonization and mixed alkali activation. The results showed that the physicochemical properties of the biochar prepared from the pretreated straw (CSB-2) were significantly enhanced compared to those of the biochar prepared from the original CS (CSB). Specifically, the specific surface area and total pore volume of CSB-2 reached 2483.43 m 2 /g and 1.4589 cm 3 /g, respectively, representing increases of 18.97 % and 19.08 % compared to CSB. In adsorption experiments using tetracycline hydrochloride and chloramphenicol as model antibiotics, CSB-2 exhibited a maximum adsorption capacity of 1322.85 mg/g and 1394.48 mg/g, respectively. These values were not only higher than those of CSB but also exceeded the performance of most bio-adsorbents. After recycling for 5 times, its adsorption capacity could still maintain more than 80 %, indicating its good stability and strong regeneration ability. This study aims to provide new insights into the development and utilization of microbial resources to further enhance the comprehensive utilization of straw. • Soil microbiota was used to pretreat corn straw to prepare enhanced biochars. • Biochars have large specific surface area and highly total pore volume. • Biochars can efficiently remove tetracycline hydrochloride and chloramphenicol. • The maximum adsorption capacities of biochars are higher than most adsorbents.