The Pennsylvania State University, Department of Agricultural and Biological Engineering, University Park, PA, 16802, USA.
USDA-Agricultural Research Service, Arid Land Agricultural Research Center, Maricopa, AZ, 85138, USA.
Chemosphere. 2023 Jul;330:138591. doi: 10.1016/j.chemosphere.2023.138591. Epub 2023 Apr 8.
Acetaminophen (ACT), sulfapyridine (SPY), ibuprofen (IBP) and docusate (DCT) are pharmaceuticals with widespread usage that experience incomplete removal in wastewater treatment systems. While further removal of these pharmaceuticals from wastewater effluent is desired prior to beneficial reuse, additional treatment technologies are often expensive and energy intensive. This study evaluated the ability of biochar produced from cotton gin waste (CG700) and walnut shells (WS800) to remove four pharmaceuticals (ACT, SPY, IBP, and DCT) from aqueous solution. Physico-chemical properties of the biochars were characterized by Brunauer-Emmett-Teller (BET) analysis, scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR), and zeta potential. The increased pyrolysis temperature during the production of WS800 led to an increase in the specific surface area and increased dehydration of the biochar represented by the loss of the OH-group. Fixed-bed column experiments were performed to determine the difference in removal efficiency between the biochars and elucidate the effects of biochar properties on the adsorption capacity for the pharmaceuticals of interest. Results showed that CG700 had a greater affinity for removing DCT (99%) and IBP (50%), while WS800 removed 72% of SPY and 68% of ACT after 24 h. Adsorption was influenced by the solution pH, surface area, net charge, and functional groups of the biochars. The mechanisms for removal included pore filling and diffusion, hydrophobic interactions, hydrogen bonding, and π-π electron donor acceptor interactions. To conduct predictive modeling of the column breakthrough curves, the Thomas, Adams-Bohart, and Yoon-Nelson models were applied to the experimental data. Results demonstrated that these models generally provided a poor fit for the description of asymmetrical breakthrough curves. Overall, the results demonstrate that biochars from cotton gin waste and walnut shells could be used as cost-effective, environmentally friendly alternatives to activated carbon for the removal of pharmaceuticals from aqueous solutions.
对乙酰氨基酚（ACT）、磺胺吡啶（SPY）、布洛芬（IBP）和多库酯（DCT）是广泛使用的药物，但在废水处理系统中无法完全去除。虽然在有益再利用之前，希望进一步从废水废水中去除这些药物，但额外的处理技术通常昂贵且能源密集。本研究评估了从棉籽绒废物（CG700）和核桃壳（WS800）生产的生物炭去除水溶液中四种药物（ACT、SPY、IBP 和 DCT）的能力。通过比表面积测试（BET）分析、扫描电子显微镜（SEM）、傅里叶变换红外光谱（FT-IR）和 ζ 电位对生物炭的物理化学性质进行了表征。WS800 生产过程中较高的热解温度导致比表面积增加，生物炭的脱水增加，这表现为 OH 基团的损失。进行了固定床柱实验，以确定生物炭之间去除效率的差异，并阐明生物炭特性对感兴趣的药物吸附能力的影响。结果表明，CG700 对去除 DCT（99%）和 IBP（50%）具有更大的亲和力，而 WS800 在 24 小时后去除了 72%的 SPY 和 68%的 ACT。吸附受溶液 pH、比表面积、净电荷和生物炭的官能团的影响。去除的机制包括孔填充和扩散、疏水相互作用、氢键和 π-π 电子供体-受体相互作用。为了对柱穿透曲线进行预测建模，将托马斯、亚当斯-博哈特和 Yoon-Nelson 模型应用于实验数据。结果表明，这些模型通常不能很好地描述不对称穿透曲线。总的来说，研究结果表明，从棉籽绒废物和核桃壳生产的生物炭可用作从水溶液中去除药物的具有成本效益、环保的活性炭替代品。
