The agricultural waste, i.e., peanut husk, was modified with iron oxide employed in Cr(VI) removal from wastewater. In this study, standard biochar (BC_PH) was prepared from the pyrolysis process from peanut husk. The prepared biochar was magnetized by impregnating the iron oxide onto the surface of the biochar to enhance the adsorption capacity of the adsorbent. The morphological analysis and physicochemical properties of the synthesized biochar (BC_PH) and magnetic biochar (MBC_PH) were evaluated systematically by SEM, XRD, BET surface area (S_BET) and point of zero charge (pH_ZPC). Batch experiments were performed to evaluate the sorption mechanism and adsorption characteristics. The pH study revealed that maximum removal efficiency obtained in acidic condition (pH_solution < pH_zpc) of the solution. The pseudo-second-order reaction model is employed to kinetic data to determine the equilibrium time, maximum removal efficacy, and the adsorption rate constants of BC_PH and MBC_PH. The equilibrium time obtained at 90 min for MBC_PH and 150 min for BC_PH, and the corresponding maximum removal efficiency values are 95.27% and 45.56%, respectively. The isotherm data corroborated that the Freundlich model is the best fit model for both adsorbents. The maximum adsorption capacities were found 8.51 mg/g for BC_PH and 75.66 mg/g for MBC_PH, respectively. The results show that the uptake capacity of the MBC_PH is increased nine times compared to biochar (BC_PH). The study concluded that the magnetic biochar (MBC_PH) has higher uptake capacity and that can be used as a promising adsorbent for the separation of Cr(VI) from aqueous solution.

将农业废料（花生壳）用氧化铁改性，该氧化铁用于去除废水中的六价铬。在这项研究中，从花生壳的热解过程中制备了标准生物炭（BC _PH）。通过将氧化铁浸渍到生物炭的表面上来磁化所制备的生物炭，以提高吸附剂的吸附能力。通过SEM，XRD，BET表面积（S _BET）和零电荷点（pH _ZPC）系统评价了合成生物炭（BC _PH）和磁性生物炭（MBC _PH）的形态分析和理化性质。）。进行批处理实验以评估吸附机理和吸附特性。pH研究表明，在酸性条件下（pH_溶液 <pH _zpc）可获得最大的去除效率。拟二级反应模型用于动力学数据，以确定平衡时间，最大去除效率以及BC _PH和MBC _PH的吸附速率常数。MBC _PH为90分钟，BC _PH为150分钟获得的平衡时间，相应的最大去除效率值分别为95.27％和45.56％。等温线数据证实了Freundlich模型是两种吸附剂的最佳拟合模型。BC _PH和MBC _PH的最大吸附容量分别为8.51 mg / g和75.66 mg / g 。结果表明，与生物炭（BC _PH）相比，MBC _PH的吸收能力提高了9倍。研究得出的结论是，磁性生物炭（MBC _PH）具有较高的吸收能力，可以用作从水溶液中分离Cr（VI）的有前途的吸附剂。