Lee Joon Hyuk, Jeon Eunkyung, Song Jung-Kun, Son Yujin, Choi Jaeho, Khim Seongjun, Kim Minju, Nam Ki-Ho
Agency for Defense Development, Yuseong P.O. Box 35, Daejeon 34186, Republic of Korea.
Department of Textile System Engineering, Kyungpook National University, Daegu 41566, Republic of Korea.
Polymers (Basel). 2023 Mar 25;15(7):1640. doi: 10.3390/polym15071640.
The manufacturing of fiber-reinforced plastics has been linked to the discharge of volatile organic compounds (VOCs), particularly toluene and benzene, which have been identified as posing substantial risks to human health and the environment. To counteract this issue, activated carbons have been suggested as a means of reducing VOC emissions through adsorption. The objective of this study was to investigate the adsorption characteristics of toluene and benzene onto activated carbons produced from coal (AC) and coconut shells (CAC). The study was carried out in an aqueous medium. The findings revealed that the AC sample with higher surface characteristics exhibited a higher adsorption capacity (toluene: 196.0784 mg g and benzene: 181.8182 mg g) in comparison to the CAC sample (toluene: 135.1351 mg g and benzene: 116.2791 mg g). The superior adsorption performance of AC on both VOCs can be attributed to its higher surface characteristics. The Langmuir model was found to be more appropriate than the Freundlich model, as indicated by the higher coefficient of determination (R) value of the Langmuir isotherm (avg. R = 0.9669) compared to that of the Freundlich isotherm (avg. R = 0.9654), suggesting the use of a monolayer adsorption mechanism. The adsorption kinetics of the samples were analyzed using the pseudo-first-order and pseudo-second-order models, and the former was found to be more fitting, indicating that the rate of adsorption is directly proportional to the concentration difference between the solution and the sample surface. The adsorption process was found to be spontaneous and favorable based on the positive value of ΔG_ads. Furthermore, the adsorption process was endothermic and disordered, as indicated by the positive values of ΔH_ads and ΔS_ads. The regeneration efficiency of all the samples was secured more than 95% upon the fifth cycle.
纤维增强塑料的制造与挥发性有机化合物（VOCs）的排放有关，尤其是甲苯和苯，它们已被确定对人类健康和环境构成重大风险。为了解决这个问题，有人提出使用活性炭通过吸附来减少VOC排放。本研究的目的是研究甲苯和苯在煤基活性炭（AC）和椰壳基活性炭（CAC）上的吸附特性。该研究在水介质中进行。研究结果表明，与CAC样品（甲苯：135.1351 mg/g，苯：116.2791 mg/g）相比，具有较高表面特性的AC样品表现出更高的吸附容量（甲苯：196.0784 mg/g，苯：181.8182 mg/g）。AC对两种VOCs的优异吸附性能可归因于其较高的表面特性。发现Langmuir模型比Freundlich模型更合适，因为Langmuir等温线的决定系数（R）值（平均R = 0.9669）高于Freundlich等温线（平均R = 0.9654），这表明使用的是单层吸附机制。使用准一级和准二级模型分析了样品的吸附动力学，发现前者更拟合，这表明吸附速率与溶液和样品表面之间的浓度差成正比。基于ΔG_ads的正值，发现吸附过程是自发且有利的。此外，吸附过程是吸热且无序的，这由ΔH_ads和ΔS_ads的正值表明。在第五个循环后，所有样品的再生效率均超过95%。
