Institute for Water Resources and Water Supply, Hamburg University of Technology, Am Schwarzenberg-Campus 3, 20173, Hamburg, Germany.
Chair of Soil Physics, University of Bayreuth, Universitätsstraße 30, 95447, Bayreuth, Germany.
J Hazard Mater. 2020 Dec 5;400:123221. doi: 10.1016/j.jhazmat.2020.123221. Epub 2020 Jun 17.
The adsorption of arsenic (V), As(V), on two porous iron oxyhydroxide-based adsorbents, namely, micro-sized tetravalent manganese feroxyhyte (μTMF) and granular ferric hydroxide (μGFH), applied in a submerged microfiltration membrane hybrid system has been investigated and modeled. Batch adsorption tests were carried out to determine adsorption equilibrium and kinetics parameters of As(V) in a bench-scale slurry reactor setup. A mathematical model has been developed to describe the kinetic data as well as to predict the As(V) breakthrough curves in the hybrid system based on the homogeneous surface diffusion model (HSDM) and the corresponding solute mass balance equation. The kinetic parameters describing the mass transfer resistance due to intraparticle surface diffusion (D) involved in the HSDM was determined. The fitted D values for the smaller (1-63 μm) and larger (1-250 μm) diameter particles of μGFH and μTMF were estimated to be 1.09 × 10 m/s and 1.53 × 10 m/s, and 2.26 × 10 m/s and 1.01 × 10 m/s, respectively. The estimated values of mass transfer coefficient/ kinetic parameters are then applied in the developed model to predict the As(V) concentration profiles in the effluent of the hybrid membrane system. The predicted results were compared with experimental data for As(V) removal and showed an excellent agreement. After validation at varying adsorbent doses and membrane fluxes, the developed mathematical model was used to predict the influence of different operation conditions on As(V) effluent concentration profile. The model simulations also exhibit that the hybrid system benefits from increasing the amount of adsorbent initially dosed and from decreasing the membrane flux (increasing the contact time).
两种多孔铁氧氢基吸附剂，即微尺度四价锰铁氧体（μTMF）和颗粒状氢氧化铁（μGFH）对砷（V），As(V)的吸附进行了研究和模拟，并应用于浸没式微滤膜混合系统。在实验室规模的浆态反应器装置中进行了批量吸附实验，以确定吸附平衡和动力学参数。建立了一个数学模型来描述动力学数据，并基于均匀表面扩散模型（HSDM）和相应的溶质质量平衡方程来预测混合系统中 As(V)的穿透曲线。确定了描述由于颗粒内表面扩散引起的传质阻力的动力学参数（D）。对于较小（1-63μm）和较大（1-250μm）直径的μGFH 和 μTMF 颗粒，HSDM 中涉及的 D 值分别估计为 1.09×10-9 m/s 和 1.53×10-9 m/s，2.26×10-9 m/s 和 1.01×10-9 m/s。然后，将估计的传质系数/动力学参数应用于开发的模型中，以预测混合膜系统出水中的 As(V)浓度分布。将预测结果与 As(V)去除的实验数据进行了比较，结果吻合良好。在改变吸附剂剂量和膜通量的条件下进行验证后，开发的数学模型用于预测不同操作条件对 As(V)出水中浓度分布的影响。模型模拟还表明，混合系统受益于最初投加的吸附剂数量的增加和膜通量的降低（接触时间的增加）。
