Study On The Greening Of Ferrofluid's Base Carriers

This paper described the preparation of nanometer magnetite by applying thechemical co-precipitation.Considering the green development of ferrofluid's basecarriers,we prepared the water-based ferrofluid using malic acid and sodiumgluconate as novel surfactants and investigated some influence factors.The heat effectand light effect in magnetic field were also studied.At last,we originally prepared theionic liquid-based ferrofluid using lycine as surfactant and investigated someinfluence factors.The specifical content are:1.The preparation of nanometer magnetite by applying the chemicalco-precipitationWe prepared the nano magnetite by applying the chemical co-precipitation.Thismethod just need ordinary equipment and facile experiment condition.The diameterof nanoparticles varies from 6nm to 9nm.These nanoparticles' saturationmagnetization is 47emu/g.We investigated some influence factors in preparation tofind the best conditions:Fe²⁺:Fe³⁺:OH^-=2:3:15;molysite solution concentrationis 0.15mol/L;temperature is 40℃.2.The preparation of water-based ferrofluid and studies of its propertiesWe applied malic acid and sodium gluconate as novel surfactants to modify thesurface property of nano magnetite.These surfactants can participate in metabolismand have low price.They can be used to prepare bio-compatible water-basedferrofluids in large scale.We investigated some influence factors on the stability offerrofluid to find out the best preparation condition:n[malic acid]:n[Fe₃O₄]=1:1,stirring time is 60min,stirring temperature is 35℃,can keep stable within 50 days;n[sodium gluconate]:n[Fe₃O₄]=0.6:1,stirring time is 60min,stirring temperature is35℃,can keep stable within 45 days.The heat effect of these ferrofluids in magneticfield were studied.Under a alternating magnetic field (63kHz,7kA/m),the maximumheating rate can reach 1.5℃/min.The light effect of these ferrofluids are obvious andmacroscopic too.3.The preparation of ionic liquid-based ferrofluid Considering the chemical stability and low vapor tension of ionic liquid,weoriginally prepared the ionic liquid-based ferrofluid using lycine as surfactant.Thecomposition,diameter,distribution and magnetism of particles are characterized.Weinvestigated some influence factors in preparation to find the best condition:stirringtemperature is 35℃,stirring time is 60min,using [C₆MeIm]BF₄ as base carrier,1mllycine,the time of using ultrasonic is 7min,this ferrofluid can keep stable within 7days.