Faculty of Modern Agricultural Engineering, Kunming University of Science & Technology, Kunming, Yunnan 650500, China.
Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650093, China.
Langmuir. 2023 Apr 25;39(16):5679-5688. doi: 10.1021/acs.langmuir.2c03353. Epub 2023 Apr 11.
Emerging pollutants, such as sulfonamide antibiotics and pharmaceuticals, have been widely detected in water and soils, posing serious environmental and human health concerns. Thus, it is urgent and necessary to develop a technology for removing them. In this work, a hydrothermal carbonization method was used to prepare the hydrochars (HCs) by pine sawdust with different temperatures. To improve the physicochemical properties of HCs, phosphoric acid (HPO) and hydrogen peroxide (HO) were used to modify these HCs, and they were referred to as PHCs and HHCs, respectively. The adsorption of sulfamethoxazole (SMX) and carbamazepine (CBZ) by pristine and modified HCs was investigated systematically. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) results indicated that the HO/HPO modification led to the formation of a disordered carbon structure and abundant pores. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy results suggested that carboxyl (-COOH) and hydroxyl (-OH) functional groups of HCs increased after modification, which is the main reason for the higher sorption of SMX and CBZ on HPO/HO-modified HCs when compared with pristine HCs. In addition, the positive correlation between -COOH/C=O and log of these two chemicals also suggested that oxygen-containing functional groups played a crucial role in the sorption of SMX and CBZ. The strong hydrophobic interaction and π-π interaction between CBZ and pristine/modified HCs resulted in its higher adsorption when compared with SMX. The results of this study provide a novel perspective on the investigation of adsorption mechanisms and environmental behaviors for organic contaminants by pristine and modified HCs.
新兴污染物，如磺胺类抗生素和药物，已在水和土壤中广泛检出，对环境和人类健康构成严重威胁。因此，开发去除它们的技术迫在眉睫且十分必要。在这项工作中，采用水热碳化法，以松木屑为原料，在不同温度下制备水热炭（HCs）。为了改善 HCs 的物理化学性质，使用磷酸（HPO）和过氧化氢（HO）对其进行改性，分别称为 PHCs 和 HHCs。系统研究了原始和改性 HCs 对磺胺甲恶唑（SMX）和卡马西平（CBZ）的吸附。扫描电子显微镜（SEM）和 X 射线衍射（XRD）结果表明，HO/HPO 改性导致无序碳结构和丰富孔的形成。X 射线光电子能谱（XPS）和傅里叶变换红外（FTIR）光谱结果表明，HCs 经改性后，其羧基（-COOH）和羟基（-OH）官能团增加，这是 HPO/HO 改性 HCs 对 SMX 和 CBZ 的吸附高于原始 HCs 的主要原因。此外，-COOH/C=O 与这两种化学物质的对数之间的正相关性也表明含氧官能团在 SMX 和 CBZ 的吸附中起关键作用。CBZ 与原始/改性 HCs 之间较强的疏水相互作用和π-π相互作用导致其吸附量高于 SMX。这项研究的结果为研究原始和改性 HCs 对有机污染物的吸附机制和环境行为提供了新的视角。
