[Progress in preparation of plant biomass-derived biochar and application in pesticide residues field].

Pesticides such as insecticides, fungicides, and herbicides play an important role in the global agricultural industry as they reduce the occurrence of crop diseases, kill pests, and remove weeds. On the other hand, these pesticides are a double-edged sword because they have both acute effects and chronic adverse effects on human health. The widespread use of pesticides has led to their persistence in soil, water, and agricultural products, thus posing a serious threat to public health. Therefore, the removal and analysis of pesticides are critical to protecting human safety and health. When removing pesticides from the environment, it is imperative to ensure high removal efficiency while preventing secondary pollution to the environment. Because of the low concentrations of pesticide residue in the environment, complex matrix, and large throughput of pesticide residue analysis, a low-cost fast pre-treatment technique that has strong selectivity and an enrichment effect on the target pesticide residue, with little environmental impact, is required. Plant biomass-derived biochar is obtained from wheat straw, corn cob, rice husk, etc. This material has a large specific surface area, high pore capacity, tunable surface functional groups, and good environmental compatibility, which make it an inexpensive and efficient adsorbent. Hence, there is a need to systematically review the knowledge regarding the application of plant-based biochar on pesticide removal and pesticide residue analysis. This paper reviews the application progress of plant biomass-derived biochar in the above mentioned two areas over the last decade. The pesticide removal applications include reducing the mobility of pesticides in soil, eliminating the pollution caused by chiral pesticides, loading pesticide-degrading bacteria, and releasing fertilizers sustainably when removing pesticide. As mentioned above, plant biomass-derived biochar has a large specific surface area, a high number of functional groups on the surface, and good environmental compatibility. Therefore, it can effectively remove pesticides or their metabolites from the environment without causing any secondary pollution. During pre-treatment, plan biomass-derived biochar is used as an adsorbent for dispersive solid-phase extraction, solid-phase microextraction, and magnetic solid-phase extraction to selectively adsorb organophosphorus and triazole pesticides in fruits and vegetables, as well as organochlorine pesticides in the aquatic environment. This paper also introduces the adsorption mechanism of plant biomass-derived biochar, where studies based on computational simulations such as the density functional theory, molecular dynamics simulation, and giant canonical Monte Carlo simulation are carefully discussed. The benefits of adopting computational simulations are also mentioned. Finally, this paper summarizes the advantages and disadvantages of using plant biomass-derived biochar in pesticide removal and pre-treatment, as well as the future research trends in this area.