Study on Stability of Al2O3-Nanoparticles with Different Dispersants

As us known, nanofluids can enhance heat transfer, and the dispersion and stability of nanofluids are the key factors to enhance heat transfer, so in this paper we mainly discussed the factors which can influence the dispersion of Al2O3-nanosuspensions. Through zeta-potential and particle size measurements in Al2O3-nanosuspensions, the influence of different pH value and the three different kinds of dispersants ( SDBS, CATB and Gum arableic) on the dispersion of Al203-nanoparticles were discussed. We find that the absolute value of zeta - potential is the biggest and the size of particles is the smallest with SDBS and Gum arabic dispersants when the pH value of nanofluids is about 8, and the absolute value of zeta - potential is the biggest and the size of particles is the smallest with CATB dispersants when the pH value of nanofluids is about 2～3. We also find that nanofluids has a good dispersion when SDBS used as dispersant, which has the biggest absolute value of Zeta - potential and the smallest particle size.