Exploring the Utilisation of Natural Biosorbents for Effective Methylene Blue Removal
Exploring the Utilisation of Natural Biosorbents for Effective Methylene Blue Removal
复制标题
DOI：
10.3390/app14010081
复制
发表时间：
2023-12
期刊：
影响因子：
--
通讯作者：
Fatih Güleç;O. Williams;Abby Samson;E. Kostas;Lee A. Stevens;Edward Lester
中科院分区：
文献类型：
--
作者：
Fatih Güleç;O. Williams;Abby Samson;E. Kostas;Lee A. Stevens;Edward Lester
本文提出了一个综合分析的吸附能力的五种截然不同的生物吸附剂来源于未经处理的生物质。通过分析粒径、pH、温度和初始染料浓度对海藻（海带）、七叶树壳、榛子壳、油菜籽渣和白木对亚甲基蓝（MB）染料的最佳吸附量的影响，研究了海藻（海带）、七叶树壳、榛子壳、油菜籽渣和白木对亚甲基蓝染料的最佳吸附量。进一步研究了吸附动力学、等温线和吸附热力学。结果表明：除七叶树壳（~130 mg/g）、榛子壳（~110 mg/g）和菜籽渣（~80 mg/g）的MB吸附量外，海带对MB的吸附量较高（~180 mg/g）；然而，白木的吸附量相对较低，低于20 mg/g。与实验结果最吻合的是伪二级动力学模型，平均绝对百分比误差最小（ε, MAPE 0.99）。虽然伪二级动力学模型通常与化学吸附有关，但低焓值（<29.30 kJ/mol）通常表明吸附过程更具有物理吸附的特征，其中涉及较弱的范德华力而不是化学吸附的较强的共价键。提出了一种包括物理吸附和化学吸附的多步吸附过程。Langmuir吸附等温线对海带和榛子壳具有较好的拟合效果。油菜籽渣和七叶树皮更符合Freundlich吸附等温线。Langmuir吸附等温线显示，对海带的最大吸附量为~500 mg/g，其次是七叶树壳（~137 mg/g）、榛子壳（~120 mg/g）和菜籽渣（~85 mg/g）。海带<七叶树壳<榛子壳< 0的吉布斯自由能为负，说明吸附过程自发发生，有利于MB的去除。研究结果表明，使用未经处理的生物质去除MB染料有可能成为海带、七叶树壳和榛子壳的整体全生命周期增值途径中的一种低成本增值选择。
This paper presents a comprehensive analysis of the adsorbent capacity of five distinctly different biosorbents derived from untreated biomasses. The optimal adsorption capacity of seaweed (Laminaria digitata), horse chestnut husk, hazelnut husk, rapeseed residue, and whitewood to remove methylene blue (MB) dye was assessed by analysing the effects of particle size, pH, temperature, and initial dye concentrations. Furthermore, the adsorption kinetics, isotherms, and adsorption thermodynamics were investigated. The results showed that relatively high MB adsorption capacity was achieved by Laminaria digitata (~180 mg/g), in addition to a reasonable MB adsorption capacity of horse chestnut husk (~130 mg/g), hazelnut husk (~110 mg/g), and rapeseed residue (~80 mg/g). However, whitewood provides a relatively low adsorption capacity of below 20 mg/g. The best fit with experimental results regardless of biosorbent type was a pseudo-second-order kinetic model with the lowest mean absolute percentage error (ε, MAPE 0.99). Although the pseudo-second-order kinetic model is often associated with chemisorption, the low enthalpy values (<29.30 kJ/mol) typically suggest that the adsorption process is more characteristic of physisorption, which involves weaker van der Waals forces rather than the stronger covalent bonds of chemisorption. This proposed a multi-step adsorption process involving both physisorption and chemisorption. The adsorption isotherm of Langmuir showed superior fitting results for Laminaria digitata and hazelnut husk. In contrast, rapeseed residue and horse chestnut husk fit better with the Freundlich adsorption isotherm. The Langmuir adsorption isotherms showed a maximum adsorption capacity of ~500 mg/g for Laminaria digitata, followed by horse chestnut husk (~137 mg/g), hazelnut husk (~120 mg/g), and rapeseed residue (~85 mg/g). The Gibbs free energy was negative for Laminaria digitata < horse chestnut husk < hazelnut husk < 0, which suggests that the removal of MB is thermodynamically favourable, as the adsorption process occurs spontaneously. The results of the study indicate that MB dye removal using untreated biomasses has the potential to be a low-cost valorisation option in the holistic whole life cycle valorisation pathway for Laminaria digitata, horse chestnut husk, and hazelnut husk.