Chemical Engineering Area, CSIR-Central Leather Research Institute (Council of Scientific & Industrial Research), Adyar, Chennai 600 020, India.
Bioresour Technol. 2013 Apr;134:94-100. doi: 10.1016/j.biortech.2013.02.012. Epub 2013 Feb 9.
Activated carbon prepared from corn cob biomass, magnetized by magnetite nanoparticles (MCCAC) was used for the adsorption of hexavalent chromium from aqueous solution. The adsorbent was characterized by SEM, TEM, XRD, VSM, surface functionality and zero-point charge. The iron oxide nanoparticles were of 50 nm sizes and the saturation magnetization value for the adsorbent is 48.43 emu/g. Adsorption was maximum at pH 2. Isotherm data were modeled using Langmuir, Freundlich and Temkin isotherm. The prepared MCCAC had a heterogeneous surface. The maximum monolayer adsorption capacity was 57.37 mg/g. Kinetic studies were carried out and the data fitted the pseudo second-order equation. The mechanism of the adsorption process was studied by incorporating the kinetic data with intraparticle diffusion model, Bangham equation and Boyd plot. The adsorption was by chemisorption and the external mass transfer was the rate-determining step. A micro column was designed and the basic column parameters were estimated.
用磁铁矿纳米粒子（MCCAC）磁化的玉米芯生物质制备的活性炭，用于从水溶液中吸附六价铬。采用 SEM、TEM、XRD、VSM、表面官能团和零点电荷对吸附剂进行了表征。氧化铁纳米粒子的尺寸为 50nm，吸附剂的饱和磁化强度值为 48.43 emu/g。吸附在 pH 2 时达到最大值。采用 Langmuir、Freundlich 和 Temkin 等温线对等温线数据进行了建模。制备的 MCCAC 具有不均匀的表面。最大单层吸附容量为 57.37mg/g。进行了动力学研究，数据符合拟二级方程。通过将动力学数据与内扩散模型、Bangham 方程和 Boyd 图结合，研究了吸附过程的机理。吸附是化学吸附，外部传质是速率控制步骤。设计了一个微柱，并估计了基本柱参数。
