El-Azazy Marwa, El-Shafie Ahmed S, Al-Meer Saeed, Al-Saad Khalid A
Department of Chemistry and Earth Sciences, College of Arts and Sciences, Qatar University, Doha 2713, Qatar.
Nanomaterials (Basel). 2020 Dec 24;11(1):30. doi: 10.3390/nano11010030.
Non-magnetic and magnetic low-cost biochar (BC) from date pits (DP) were applied to remove tigecycline (TIGC) from TIGC-artificially contaminated water samples. Pristine biochar from DP (BCDP) and magnetite-decorated biochar (MBC-DP) were therefore prepared. Morphologies and surface chemistries of BCDP and MBC-DP were explored using FT-IR, Raman, SEM, EDX, TEM, and BET analyses. The obtained IR and Raman spectra confirmed the presence of magnetite on the surface of the MBC-DP. SEM results showed mesoporous surface for both adsorbents. BET analysis indicated higher amount of mesopores in MBC-DP. Box-Behnken (BB) design was utilized to optimize the treatment variables (pH, dose of the adsorbent (AD), concentration of TIGC [TIGC], and the contact time (CT)) and maximize the adsorptive power of both adsorbents. Higher % removal (%R), hitting 99.91%, was observed using MBC-DP compared to BCDP (77.31%). Maximum removal of TIGC (99.91%) was obtained using 120 mg/15 mL of MBC-DP for 10 min at pH 10. Equilibrium studies showed that Langmuir and Freundlich isotherms could best describe the adsorption of TIGC onto BCDP and MBC-DP, respectively, with a maximum adsorption capacity () of 57.14 mg/g using MBC-DP. Kinetics investigation showed that adsorption of TIGC onto both adsorbents could be best-fitted to a pseudo-second-order (PSO) model.
将来自枣核（DP）的非磁性和磁性低成本生物炭（BC）应用于从人工受替加环素（TIGC）污染的水样中去除替加环素。因此制备了来自枣核的原始生物炭（BCDP）和磁铁矿修饰的生物炭（MBC-DP）。使用傅里叶变换红外光谱（FT-IR）、拉曼光谱、扫描电子显微镜（SEM）、能谱分析（EDX）、透射电子显微镜（TEM）和比表面积分析仪（BET）分析对BCDP和MBC-DP的形态和表面化学性质进行了研究。获得的红外光谱和拉曼光谱证实了MBC-DP表面存在磁铁矿。扫描电子显微镜结果显示两种吸附剂均具有中孔表面。BET分析表明MBC-DP中的中孔数量更多。采用Box-Behnken（BB）设计来优化处理变量（pH值、吸附剂剂量（AD）、替加环素浓度[TIGC]和接触时间（CT）），并使两种吸附剂的吸附能力最大化。与BCDP（77.31%）相比，使用MBC-DP时观察到更高的去除率（%R），达到99.91%。在pH值为10的条件下，使用120 mg/15 mL的MBC-DP处理10分钟，替加环素的最大去除率为99.91%。平衡研究表明，Langmuir等温线和Freundlich等温线分别最能描述替加环素在BCDP和MBC-DP上的吸附情况，MBC-DP的最大吸附容量（）为57.14 mg/g。动力学研究表明，替加环素在两种吸附剂上的吸附最符合准二级（PSO）模型。
