Center for Environmental Studies, Department of Applied Chemistry and Production Systems, Faculty of Chemical Sciences, University of Cuenca, Cuenca, Ecuador.
Water and Environmental Health Research Group, Environmental Sciences Institute (IUCA), Department of Chemical Engineering and Environmental Technology, School of Engineering and Architecture (EINA), University of Zaragoza, Zaragoza, Spain.
Sci Total Environ. 2021 Jan 1;750:141498. doi: 10.1016/j.scitotenv.2020.141498. Epub 2020 Aug 6.
This work examined the adsorption capacity of sugarcane bagasse (SB) for the removal of ciprofloxacin (CPX) from water using batch experiments and a fixed bed column and compared its adsorption performance with a powdered activated commercial carbon (PAC). Both adsorbents achieved a similar percentage removal of about 78% with doses of 3 g L of SB and 0.3 g L of PAC (20 mg L initial CPX concentration at 30 °C). The maximum removal was obtained at a pH between 6 and 8. SB adsorption isotherms were fitted to the Langmuir, BET and Freundlich models showing a maximum adsorption capacity of 13.6 mg g. The kinetic data for both SB and PAC fitted the pseudo second-order model (R = 0.99). The adsorption process was faster on the SB (65% of elimination in the first 5 min) than on the PAC. The study of the adsorbent properties shows that SB is a macroporous solid with a specific surface area 250 times smaller than PAC. The thermodynamic results show that SB adsorption was physical and exothermic. The main suggested interactions between CPX and SB are electrostatic attraction, hydrogen bonding and dipole-dipole interactions. The experiments carried out in a fixed bed show that the adsorption capacity at breakthrough increases with the bed height. The adsorption capacity at saturation time was 9.47 mg g at a flow rate of 3 mL min, a bed height of 14 cm, and a diameter of 1.5 cm. The experimental data were fitted to the Bohart-Adams model (R = 0.98). These results highlight the capacity of sugarcane bagasse to adsorb ciprofloxacin from water, illustrating its potential as a low-cost adsorbent.
这项工作研究了甘蔗渣（SB）在使用批量实验和固定床柱去除水中环丙沙星（CPX）的吸附能力，并将其吸附性能与粉末状商业活性炭（PAC）进行了比较。两种吸附剂在剂量为 3 g/L 的 SB 和 0.3 g/L 的 PAC（初始 CPX 浓度为 20 mg/L，在 30°C 下）时，都达到了约 78%的相似去除百分比。最大去除率在 pH 值为 6 到 8 之间获得。SB 吸附等温线拟合朗缪尔、BET 和 Freundlich 模型，显示最大吸附容量为 13.6 mg/g。SB 和 PAC 的动力学数据都拟合伪二级模型（R = 0.99）。SB 的吸附过程比 PAC 更快（在前 5 分钟内消除了 65%）。对吸附剂性质的研究表明，SB 是一种具有比 PAC 小 250 倍的比表面积的大孔固体。热力学结果表明，SB 吸附是物理和放热的。SB 与 CPX 之间的主要建议相互作用是静电吸引、氢键和偶极-偶极相互作用。在固定床中进行的实验表明，穿透时的吸附容量随床高增加而增加。在流速为 3 mL/min、床高为 14 cm、直径为 1.5 cm 的条件下，饱和时间的吸附容量为 9.47 mg/g。实验数据拟合 Bohart-Adams 模型（R = 0.98）。这些结果突出了甘蔗渣从水中吸附环丙沙星的能力，说明了其作为低成本吸附剂的潜力。
