Abstract

The modified abandoned fine blue-coke (MAFB) was used to remove phenol from the aqueous solution efficiently. The effects of initial concentration, temperature, pH, and co-existing salt ions of the phenol solution on the adsorption capacity of MAFB for phenol were investigated. The adsorption equilibrium, thermodynamic, kinetic, and adsorbent regeneration were studied simultaneously. The results showed that the maximum adsorption capacity of phenol onto the MAFB was obtained as 151.74 mg g⁻¹ at the initial solution concentration of 1100 mg L⁻¹, the temperature of 328 K, and pH of 4.0–6.5. The salt ions of Na⁺, Cl⁻, SO^2-₄ had little effect on the adsorption capacity. The adsorption isotherm belongs to the L isotherm and the Langmuir model can better describe the adsorption process. Thermodynamics results indicated that the adsorption was entropy increase, spontaneous and endothermic process. The adsorption kinetics was found to follow the pseudo-second-order model. The physical adsorption of π–π dispersion interactions could be used to describe the adsorption mechanism. The 60% regeneration rate of the MAFB was reached by three times alcohol desorption at 323 K for 4 h. Compared with other adsorbents, MAFB has better phenol adsorption performance, which makes it a promising and excellent adsorbent to remove phenol from wastewater.

摘要

改性废弃细蓝焦（MAFB）用于有效去除水溶液中的苯酚。研究了苯酚溶液的初始浓度、温度、pH值和共存盐离子对MAFB对苯酚吸附能力的影响。同时研究了吸附平衡、热力学、动力学和吸附剂再生。结果表明，在初始溶液浓度为 1100 mg L ^-1、温度为 328 K、pH 为 4.0-6.5 时，MAFB 对苯酚的最大吸附量为 151.74 mg g ^{-1 。}Na ⁺ , Cl ^- , SO ^2- _{4的盐离子}对吸附能力影响不大。吸附等温线属于L等温线，Langmuir模型能更好地描述吸附过程。热力学结果表明吸附是熵增、自发和吸热的过程。发现吸附动力学遵循准二级模型。π-π 分散相互作用的物理吸附可用于描述吸附机理。通过在 323 K 下 4 小时进行 3 次酒精解吸，MAFB 的再生率达到了 60%。与其他吸附剂相比，MAFB具有更好的苯酚吸附性能，使其成为去除废水中苯酚的有前途的优良吸附剂。