Del Vecchio Paola, Haro Nathalia K, Souza Fernanda Siqueira, Marcílio Nilson Romeu, Féris Liliana A
Department of Chemical Engineering, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil E-mail:
Department of Chemical Engineering, University Center Ritter dos Reis, Porto Alegre, RS, Brazil.
Water Sci Technol. 2019 May;79(10):2013-2021. doi: 10.2166/wst.2019.205.
Pharmaceutical compounds are essential to preserve human and animal welfare, as well as to prevent illnesses. However, the elevated consumption of drugs, followed by incorrect disposal and inefficient wastewater treatment, may increase their environmental risk. In the case of antibiotics, such as ampicillin, some of the already known consequences are bacterial resistance and some toxic interactions with aquatic organisms. The scope of the present work is to investigate the removal of ampicillin through batch adsorption experiments onto granular activated carbon (GAC). The influence of pH and phase contact time were evaluated. Pseudo-first order, pseudo-second order and intraparticle diffusion models were adjusted to experimental data to determine process kinetics. In order to study adsorption equilibrium and thermodynamics parameters, isotherms at 298 K, 298 K and 308 K were constructed. The models of Langmuir, Freundlich and Sips fitted to experimental data. The best results (73% of removal, residual concentration 5.2 mg L) were reached at pH 6 and 120 minutes of contact time. Pseudo-first order model better represented the adsorption kinetics (R = 0.99), while the Langmuir equation suited well the experimental isotherms at 288 K and 298 K (R = 0.998 and R = 0.991) and the Sips equation better represented the system at 308 K (R = 0.990). Thermodynamic parameters were estimated as ΔG° = -6,000 J mol; -6,700 J mol; -7,500 J mol at 288 K, 298 K and 308 K respectively, ΔH° = 14,500 J mol and ΔS° = 71.0 J mol K. The results indicate that this process is spontaneous, efficient and potentially applicable in the removal of ampicillin from water.
药物化合物对于维护人类和动物健康以及预防疾病至关重要。然而，药物消费的增加，再加上不正确的处置和低效的废水处理，可能会增加其环境风险。就抗生素而言，如氨苄青霉素，一些已知的后果是细菌耐药性以及与水生生物的一些毒性相互作用。本研究的范围是通过在颗粒活性炭（GAC）上进行间歇吸附实验来研究氨苄青霉素的去除情况。评估了pH值和相接触时间的影响。将伪一级、伪二级和颗粒内扩散模型与实验数据进行拟合以确定过程动力学。为了研究吸附平衡和热力学参数，构建了298K、298K和308K下的等温线。Langmuir、Freundlich和Sips模型与实验数据拟合良好。在pH值为6且接触时间为120分钟时取得了最佳结果（去除率73%，残留浓度5.2mg/L）。伪一级模型更好地描述了吸附动力学（R = 0.99），而Langmuir方程在288K和298K下很好地拟合了实验等温线（R = 0.998和R = 0.991），Sips方程在308K下更好地描述了该系统（R = 0.990）。热力学参数估计分别为288K、298K和308K时的ΔG° = -6,000J/mol；-6,700J/mol；-7,500J/mol，ΔH° = 14,500J/mol，ΔS° = 71.0J/(mol·K)。结果表明该过程是自发的、高效的，并且有可能应用于从水中去除氨苄青霉素。
