载镁含油污泥基活性炭的制备及吸附去除甲基橙性能

Magnesium-loaded oily sludge-based activated carbon efficiently adsorbs methyl orange

摘要:

以含油污泥为活性炭原料，MgCl2为活化剂，二步热解得到载镁污泥基活性炭 (M-OS)，通过单因素实验确定了最佳制备条件，并研究其对甲基橙的吸附性能。结果表明，当溶液初始 pH为5、甲基橙初始浓度为100 mg/L，反应时间为360 min， M-OS 投加量为 1.5 g/L时，M-OS 对水溶液中甲基橙的吸附性能表现最佳；BET、SEM、X射线（XRD、XPS）和红外光谱（FTIR）研究说明镁主要是以MgO形式存在于活性炭表面，吸附过程主要是表面络合、羟基、孔隙填充等多种吸附力作用结合；动力学模型和等温模型的拟合结果进一步证实吸附过程中起主要作用的是化学吸附，吸附过程属于自发过程，且M-OS对甲基橙的最大吸附量为3901.87 mg/g。研究结果可为含油污泥的资源化利用和处理水体中染料提供一种潜在的有效途径。

Abstract:

Magnesium-loaded sludge-based activated carbon ( M-OS ) was obtained by two-step pyrolysis using oily sludge as raw material and MgCl2 as activator. The optimum preparation conditions were determined by single factor experiment, and its adsorption performance for methyl orange was studied.The adsorption performance of M-OS for methyl orange was investigated. Results indicated that the optimal adsorption performance of M-OS for methyl orange in aqueous solution was achieved under the conditions of an initial solution pH of 5, an initial methyl orange concentration of 100 mg/L, a reaction time of 360 minutes, and an M-OS dosage of 1.5 g/L. SEM, XRD, XPS, and FTIR analyses revealed that magnesium predominantly existed on the surface of the activated carbon in the form of MgO. The adsorption process was mainly governed by multiple adsorption forces, including surface complexation, hydroxyl groups, and pore filling. Kinetic model and isothermal model further confirmed that chemical adsorption played a significant role in the adsorption of methyl orange by M-OS. The process was spontaneous, and the maximum adsorption capacity of M-OS for methyl orange was 3901.87 mg/g. These findings provide a potential and effective method for the resource utilization of oily sludge and the treatment of dye-contaminated wastewater.