University of Chemical Technology and Metallurgy, 8 Kliment Ohridski Blvd, 1756 Sofia, Bulgaria.
Water Sci Technol. 2010;62(4):883-91. doi: 10.2166/wst.2010.927.
The mechanism of 4-nitrophenol (4-NP) and 2,4-dinitrophenol (2,4-DNP) adsorption on perfil-natural mineral taken from Bulgarian deposits, in a fixed-bed column was investigated. The single component experiments were conducted at constant initial sorbate concentration, volumetric flow rate, temperature and pH. The effect of adsorbent bed depth (Z 1, 2, 3, 6 cm) and sorbate nature on the adsorption capacity, mass transfer parameters and mechanisms was studied. The equilibrium behaviour of the system 4-NP-perfil was described by Langmuir, Freundlich and Redlich-Peterson models. The single resistance Thomas model, including Reynolds-Richards and Walter solutions, and the two-resistance Arnold model were applied for mathematical modeling of the experimental data. The comparative analyses indicated that external mass transfer was the rate limiting mechanism during the initial adsorption stages, while intraparticle diffusion was dominant in the middle and high concentration ranges. The effect of axial dispersion on the dynamics of adsorption was evaluated.
研究了从保加利亚矿床中提取的天然矿物 perfil 对 4-硝基苯酚（4-NP）和 2,4-二硝基苯酚（2,4-DNP）的吸附机制，采用固定床柱。在恒定的初始吸附质浓度、体积流速、温度和 pH 条件下进行了单组分实验。研究了吸附剂床层深度（Z1、2、3、6cm）和吸附质性质对吸附容量、传质参数和机制的影响。用 Langmuir、Freundlich 和 Redlich-Peterson 模型描述了系统 4-NP-perfil 的平衡行为。采用单阻力 Thomas 模型，包括 Reynolds-Richards 和 Walter 解，以及双阻力 Arnold 模型对实验数据进行了数学建模。比较分析表明，在初始吸附阶段，外部传质是速率限制机制，而在中高浓度范围内，颗粒内扩散占主导地位。评价了轴向扩散对吸附动力学的影响。
