Adsorption of sulfonamides on biochars derived from waste residues and its mechanism
Adsorption of sulfonamides on biochars derived from waste residues and its mechanism
复制标题
废渣生物炭对磺胺类药物的吸附及其机理
DOI：
10.1016/j.jhazmat.2020.124291
复制
发表时间：
2021-01-25
影响因子：
13.6
通讯作者：
Zou, Xiaoming
中科院分区：
文献类型：
--
作者：
Fan, Yuxing;Huang, Liangliang;Zou, Xiaoming
人们已将废渣制备成生物炭（BC）吸附剂，以低成本去除磺酰胺（SA），但不同BC对SA吸附性能差异的机制尚不清楚。因此，研究了两种SA（磺胺嘧啶和磺胺噻唑）对来自废渣（污水污泥（SB）、猪粪（PB）和稻草（RB））的三种BC的吸附特性。结果表明，吸附机制为化学吸附，在不同测试条件（pH、Ca2+、腐植酸）下，RB是首选的BC，其次是PB和SB。为了解释这一现象，进行了 FTIR、XRD 和 XPS 分析，结果表明 SB 的 C 含量最低，并且 PB 和 RB 的两个 O 官能团（(CO)-O-= 和 C-O）的浓度存在非常显着的差异（P < 0.01）。密度泛函理论计算表明SA在BC上的吸附机制主要是通过pi-pi电子供体受体相互作用和H键。含有C-O(BC(OH))的SAs-BC和含有(CO)-O-=(BC((CO)-O-=))的SAs-BC之间的pi相互作用没有显着差异，而SAsBC(OH)的H键强度远强于SAs-BC((CO)-O-=)。
Waste residues have been prepared as biochar (BC) adsorbents to remove sulfonamides (SAs) at low cost, but the mechanisms of the differences in the SA adsorption performance of different BCs are not clear. Thus, the adsorption characteristics of two SAs (sulfadiazine and sulfathiazole) on three BCs derived from waste residues (sewage sludge (SB), pig manure (PB), and rice straw (RB)) were investigated. The results showed that the adsorption mechanism was chemisorption and RB was the preferred BC under the different tested conditions (pH, Ca2+, and humic acid), followed by PB and SB. To interpret the phenomena, FTIR, XRD, and XPS analyses were performed and results indicated that SB had the lowest C content, and there was a very significant difference in the concentrations of the two O functional groups ((CO)-O-= and C-O) for PB and RB (P < 0.01). Density functional theory calculations revealed that the mechanisms of SA adsorption onto BCs were mainly through pi-pi electron donor acceptor interactions and H bonds. There was no significant difference in the pi interactions between the SAs-BC containing C-O (BC(OH)) and the SAs-BC containing (CO)-O-= (BC((CO)-O-=)), whereas the H bond strength of SAsBC(OH) was much stronger than that of SAs-BC((CO)-O-=).