PROCESS FOR PREPARING MAGNETIC NANOFLUID IN VEGETABLE OIL

The invention relates to a process for preparing a magnetic nanofluid to be used as an insulation fluid and cooling medium in power transformers. According to the invention, the process comprises the synthesis of magnetic nanoparticles FeOby the hydrothermal method, hydrophobic steric stabilization by coating with a polymeric coat, using ultrasonication emulsifying method and dispersion of the coated synthesised nanoparticles into oil, where the suspension has volume concentrations of 0.3...1.5% magnetic nanoparticles, it is subjected to ultrasonication for 4...8 h at the ambient temperature, to result in a magnetic fluid having a saturation magnetization of 1.85...3.08 emu/g, a remanent magnetization of 0.72...0.90 emu/g and a coercive field of 235...268.9 Oe. Invenţia se referă la un procedeu de obţinere a unui nanofluid magnetic, utilizat ca fluid izolator şi agent de răcire la transformatoare de putere. Procedeul conform invenţiei constă în sinteza de nanoparticule magnetice de FeOprin metoda hidrotermală, stabilizarea sterică hidrofobă, prin acoperire cu un înveliş polimeric, prin metoda emulsionării cu ultrasonare, şi dispersia în ulei a nanoparticulelor sintetizate acoperite, suspensia având concentraţii volumice de 0,3...1,5% nanoparticule magnetice, se ultrasonează timp de 4...8 h la temperatura camerei, rezultând un fluid magnetic având o magnetizaţie la saturaţie de 1,85...3,08 emu/g, magnetizaţie remanentă 0,72...0,90 emu/g şi câmp coercitiv 235...268,9 Oe.