利用低成本吸附剂从废果皮中制备,用于去除废水中的选定活性和碱性染料的可持续利用。
Sustainable use of low-cost adsorbents prepared from waste fruit peels for the removal of selected reactive and basic dyes found in wastewaters.
机构信息
Department of Chemistry, International Hellenic University, 65404, Kavala, Greece.
Department of Chemistry, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece.
出版信息
Environ Sci Pollut Res Int. 2024 Feb;31(10):14662-14689. doi: 10.1007/s11356-024-31868-3. Epub 2024 Jan 27.
Agricultural wastes are potential sustainable adsorbents since they are available in large quantities, are low-cost, and may require little or no treatment, in some cases. In this study, several fruit peels, such as banana, orange, and pomegranate, were collected from local markets and prepared by a simple and eco-friendly method and used as natural adsorbents for the removal of both anionic (Reactive Red 120 (RR120), Reactive Black 5 (RB5), Remazol Brilliant Blue R (RBBR)) and cationic Methylene Blue (MB) dyes found in wastewaters. Many industries, such as leather and textiles, can release huge amounts of synthetic dyes into the wastewater during dyeing processes. These are one of the most important pollutants of water pollution as they cause enormous damage to the water body and also affect the health of organisms due to their toxicity and carcinogenicity. The search for a sustainable and at the same time efficient material for the removal of a wide variety of dyes is the innovation of this work. These peels were prepared by washing, drying, grinding, and finally sieving, under natural sustainable conditions. Porosometry (BET analysis), FTIR, SEM/EDS, and XRD techniques were used to characterize the fruit peels before and after the adsorption process. Factors affecting the adsorption of dyes (adsorbent dosage, pH solution, initial concentration of dyes, contact time, and temperature) were investigated. According to the results, in terms of the effectiveness of fruit peels as (natural) adsorbent materials, for anionic dyes, 5.0-6.0 g/L of banana or orange dry peels was sufficient to remove near or even more than 90% anionic dyes at pH 2.0, and 4.0 g/L was sufficient to remove 98% of cationic MB dye at pH 9.0. Similar amount of pomegranate peels had lower efficiency for anionic dyes (50-70%), while cationic MB was still efficiently removed (98%) at pH 9.0. Moreover, the adsorption process in all cases was found to better fit to pseudo-second-order model, in comparison to pseudo-first-order model. According to isotherms, Freundlich model fitted better in some cases to the equilibrium data, while the Langmuir model in others. Finally, this study demonstrates the viability of reusing the banana, orange, and pomegranate peel adsorbents for eight, four, and five cycles, showing a gradual reduction of around 50% of their effectiveness.
农业废弃物是一种潜在的可持续吸附剂,因为它们数量大、成本低,在某些情况下可能不需要或只需稍加处理。在这项研究中,我们从当地市场收集了几种果皮,如香蕉皮、橙皮和石榴皮,通过简单且环保的方法进行制备,并将其用作天然吸附剂,以去除废水中的阴离子(活性红 120(RR120)、活性黑 5(RB5)、雷玛素亮蓝 R(RBBR))和阳离子亚甲蓝(MB)染料。许多行业,如皮革和纺织业,在染色过程中会将大量合成染料释放到废水中。这些是水污染最重要的污染物之一,因为它们会对水体造成巨大破坏,而且由于其毒性和致癌性,还会影响生物体的健康。寻找一种可持续且同时高效的材料来去除各种染料是这项工作的创新之处。这些果皮是在自然可持续条件下通过洗涤、干燥、研磨和最后筛分来制备的。在吸附过程前后,使用比表面积和孔隙度分析(BET 分析)、傅里叶变换红外光谱(FTIR)、扫描电子显微镜/能谱(SEM/EDS)和 X 射线衍射(XRD)技术对果皮进行了表征。研究了影响染料吸附的因素(吸附剂用量、溶液 pH 值、染料初始浓度、接触时间和温度)。根据结果,就果皮作为(天然)吸附材料的有效性而言,对于阴离子染料,在 pH 值为 2.0 时,5.0-6.0 g/L 的香蕉或橙干皮足以去除近 90%或甚至更多的阴离子染料,而 4.0 g/L 足以去除 pH 值为 9.0 时 98%的阳离子 MB 染料。类似量的石榴皮对阴离子染料的效率较低(50-70%),而阳离子 MB 仍能在 pH 值为 9.0 时有效去除(98%)。此外,与准一级模型相比,在所有情况下,吸附过程都更符合准二级模型。根据吸附等温线,在某些情况下,Freundlich 模型更适合平衡数据,而在其他情况下,Langmuir 模型更适合。最后,本研究表明,香蕉、橙和石榴皮吸附剂在经过 8、4 和 5 次循环后可重复使用,其有效性逐渐降低约 50%。