Gastelo Elmer, Montes de Oca Juan, Carpio Edward, Espinoza Juan, García Pilar, Ponce Silvia, Rodriguez Juan
Center for the Development of Advanced Materials and Nanotechnology, Universidad Nacional de Ingenieria, Av. Tupac Amaru 210, Rimac, Lima 15333, Peru.
Istituto de Investigación Científica (I.D.I.C), Universidad de Lima, Av. Javier Prado Este 4600, Surco, Lima 15023, Peru.
Materials (Basel). 2019 Jun 29;12(13):2103. doi: 10.3390/ma12132103.
This paper focuses on the synthesis of cobalt ferrite nanoparticles by the sol-gel method and their photocatalytic activity to eliminate bacteria in aqueous media at two different scales: in a laboratory reactor and a solar pilot plant. Cobalt ferrite nanoparticles were prepared using Co(II) and Fe(II) salts as precursors and cetyltrimethyl ammonium bromide as a surfactant. The obtained nanoparticles were characterized by X-ray diffraction, scanning and transmission electron microscopy. () strain ATCC 22922 was used as model bacteria for contact biocidal analysis carried out by disk diffusion method and photocatalysis under an ultraviolet A (UV-A) lamp for laboratory analysis and solar radiation (radiation below 350 W/m in a typical cloudy day) for the pilot plant analysis. The results showed that cobalt ferrite nanoparticles have an average diameter of (36 ± 20) nm and the X-ray diffraction pattern shows a cubic spinel structure. Using the disk diffusion technique, it was obtained inhibition zones of (17 ± 2) mm diameter. Results confirm the photocatalytic elimination of in water samples with remaining bacteria below 1% of the initial concentration during the experiment time (30 min for laboratory tests and 1.5 h for pilot plant tests).
本文重点研究了通过溶胶-凝胶法合成钴铁氧体纳米颗粒及其光催化活性，以在两种不同规模下消除水介质中的细菌：在实验室反应器和太阳能中试装置中。使用Co(II)和Fe(II)盐作为前驱体，十六烷基三甲基溴化铵作为表面活性剂制备钴铁氧体纳米颗粒。通过X射线衍射、扫描和透射电子显微镜对所得纳米颗粒进行了表征。使用()菌株ATCC 22922作为模型细菌，通过纸片扩散法进行接触杀菌分析，并在紫外A(UV-A)灯下进行光催化，用于实验室分析；在典型阴天辐射低于350W/m的太阳能辐射下进行中试装置分析。结果表明，钴铁氧体纳米颗粒的平均直径为(36±20)nm，X射线衍射图谱显示为立方尖晶石结构。使用纸片扩散技术，获得了直径为(17±2)mm的抑菌圈。结果证实，在实验时间内（实验室测试30分钟，中试装置测试1.5小时），水样中的细菌通过光催化消除，剩余细菌低于初始浓度的1%。
