This study investigated the effect of tannic acid (TA) on the adsorption efficiency of activated biochar (ABC) prepared from reed biomass regarding the removal of methylene blue (MB) from aqueous solution. The structure and chemical properties of the obtained ABC adsorbent were characterized by XRD, FTIR, N₂ adsorption-desorption isotherms, and scanning electron microscopy. After the HNO₃ activation of the original biochar (BC), the well-developed porous surface structure of ABC was observed with a considerable increase in the specific surface area. The adsorption behavior of MB onto ABC was determined with the presence of TA (pre-loading versus co-introduction with solute). Results demonstrated that the removal of MB was promoted in the presence of TA solutions with pH ranging from 4.0 to 8.0, and an increase of the initial concentration of TA (from 10 to 50 mg/L) caused a more pronounced promotion effect. The adsorption of MB onto ABC followed the Elovich kinetic model, suggesting a heterogeneous multilayer adsorption process. The adsorption data were best described by the Sips isotherm model, showing a maximum adsorption amount of 77.35 mg/g in the presence of TA, which was much higher than many reported adsorbents. The adsorption mechanism appeared to be related to electrostatic interaction, hydrogen bonding, ion exchange, n-π/π-π interaction, etc. Findings of the present work highlighted the positive effect of TA on the adsorptive removal of MB by ABC, and were also beneficial for developing reed-derived biochar as an engineered absorbent for removal of toxic dyes from aqueous solution.

这项研究调查了鞣酸（TA）对从芦苇生物质制备的活性炭（ABC）的吸附效率的影响，该活性炭关于从水溶液中去除亚甲基蓝（MB）的作用。通过XRD，FTIR，N ₂吸附-脱附等温线，扫描电子显微镜对所得ABC吸附剂的结构和化学性质进行了表征。HNO _3之后激活原始生物炭（BC）后，观察到ABC的发达多孔表面结构，比表面积显着增加。MB在ABC上的吸附行为是通过TA的存在来确定的（预加载与与溶质的共引入）。结果表明，在pH为4.0至8.0的TA溶液存在下，MB的去除得到了促进，并且TA初始浓度的增加（从10至50 mg / L）引起了更明显的促进作用。MB在ABC上的吸附遵循Elovich动力学模型，表明存在非均相的多层吸附过程。吸附数据最好用Sips等温模型描述，显示在TA存在下最大吸附量为77.35 mg / g，比许多报道的吸附剂高得多。