农业废物是潜在的可持续吸附剂,因为它们大量可用,是低成本的,可能需要很少或不需要治疗,在某些情况下。在这项研究中,几个水果皮,比如香蕉,橙色,还有石榴,从当地市场收集,并通过简单且环保的方法制备,并用作去除两种阴离子的天然吸附剂(反应红120(RR120),活性黑5(RB5),在废水中发现的Remazol亮蓝R(RBBR)和阳离子亚甲基蓝(MB)染料。许多行业,如皮革和纺织品,在染色过程中会向废水中释放大量的合成染料。这些污染物是水污染中最重要的污染物之一,因为它们对水体造成巨大的损害,并且由于其毒性和致癌性而影响生物的健康。寻找可持续的,同时有效的材料来去除各种染料是这项工作的创新。这些果皮是通过洗涤制备的,干燥,研磨,最后筛分,在自然可持续条件下。Porosometry(BET分析),FTIR,SEM/EDS,采用XRD技术对吸附前后果皮进行了表征。影响染料吸附的因素(吸附剂用量、pH溶液,染料的初始浓度,接触时间,和温度)进行了调查。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,5.0-6.0g/L的香蕉或橙色干果皮在pH2.0下足以除去接近或甚至超过90%的阴离子染料,并且4.0g/L在pH9.0下足以除去98%的阳离子MB染料。相似量的石榴皮对阴离子染料的效率较低(50-70%),而阳离子MB在pH9.0时仍被有效去除(98%)。此外,发现在所有情况下的吸附过程都更好地拟合伪二阶模型,与伪一阶模型相比。根据等温线,Freundlich模型在某些情况下更适合均衡数据,而其他的Langmuir模型。最后,这项研究证明了重复使用香蕉的可行性,橙色,石榴皮吸附剂为八,四,五个周期,显示其效力的50%左右逐渐降低。
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.