Centre for Nanobiotechnology, VIT, Vellore, Tamil Nadu, India.
Centre for Nanobiotechnology, VIT, Vellore, Tamil Nadu, India.
J Environ Manage. 2020 Jan 15;254:109812. doi: 10.1016/j.jenvman.2019.109812. Epub 2019 Nov 14.
Antibiotics, one of the most abundant contaminants in the natural water systems possess various difficulties to remediate through conventional water treatment methods. Tetracycline (TC) remains one of the most widely used antibiotics for human and veterinary applications because of its broad-spectrum antibacterial activity. In the current study, we have employed nano zero-valent technology-based antibiotic remediation. In a first of its kind work, we applied bimetallic nZVI-Cu nanoparticles synthesized using pomegranate rind extract for remediation. TC removal of 72 ± 0.5% (initial TC concentration 10 mg/L) was obtained with the nZVI-Cu concentration of 750 mg/L at pH 7. To overcome the colloidal instability and enhance TC removal further, the bimetallic nanoparticles were formed in-situ over bentonite. The bentonite supported composite (B/nZVI-Cu) was used to treat TC an initial concentration of 10 mg/L and the results confirmed significant enhancement in removal with a substantially decreased nanoparticle loading. Using only 150 mg/L of B/nZVI-Cu at pH 7, 95 ± 0.05% of TC could be removed. The nanoparticles and the composites were characterized by SEM, FT-IR, and XRD analyses. The removal process was followed by UV-Visible analyses in conjunction with TOC, ORP and LCMS measurements. For treatment using B/nZVI-Cu, the reusability of the composite was established up to three cycles of operation, and the process was validated in the real water systems. Substantially decreased residual toxicity of the composite treated TC solution lends credence to the environmental sustainability of the process.
抗生素是天然水系中最丰富的污染物之一，通过传统的水处理方法很难进行修复。四环素（TC）因其广谱抗菌活性而被广泛用于人类和兽医应用，是最广泛使用的抗生素之一。在目前的研究中，我们采用了基于纳米零价技术的抗生素修复方法。在首例此类工作中，我们应用了使用石榴皮提取物合成的双金属 nZVI-Cu 纳米颗粒进行修复。在 pH 值为 7 时，当 nZVI-Cu 浓度为 750mg/L 时，TC 的去除率为 72±0.5%（初始 TC 浓度为 10mg/L）。为了克服胶体不稳定性并进一步提高 TC 的去除率，在膨润土上原位形成了双金属纳米颗粒。将膨润土负载的复合材料（B/nZVI-Cu）用于处理初始浓度为 10mg/L 的 TC，结果证实去除率显著提高，而纳米颗粒的负载量大大降低。在 pH 值为 7 时，仅使用 150mg/L 的 B/nZVI-Cu，就可以去除 95±0.05%的 TC。通过 SEM、FT-IR 和 XRD 分析对纳米颗粒和复合材料进行了表征。通过 UV-可见分析结合 TOC、ORP 和 LCMS 测量来跟踪去除过程。对于使用 B/nZVI-Cu 的处理，该复合材料在三个操作循环中可重复使用，并且在实际水系统中验证了该过程。经复合处理后 TC 溶液的残余毒性显著降低，这证明了该过程具有环境可持续性。
