Experimental on viscosity and isobaric heat capacity of [C4mim][BF4] ionic liquid with MWCNT nanoparticles

Abstract

Ionic liquids have been regarded lately as a new possible candidate for heat transfer fluids because of their unique and tunable properties due to their intrinsic structure composed from anions and cations. One of the ionic liquids’ relevant properties is that they contribute to the suspensions stability, if nanoparticles are added in order to rise the thermal properties. This article presents an experimental study that is part of a larger work on nanocolloids having [C4mim][BF4] ionic liquid as the base fluid. In this paper, suspensions of MWCNT nanoparticles in [C4mim][BF4] are discussed in terms of viscosity and isobaric heat capacity. More exactly, four suspensions (0.025, 0.05, 0.075 and 0.1 %wt.) were manufactured and further checked for their changes in properties at ambient temperature and in successive cycles of heating up to 333.15 followed by cooling. Results revealed that the addition of nanoparticles is changing the flow from Newtonian (for the ionic liquid) to non – Newtonian. Plus, the viscosity is increasing when MWCNT is added, while the heating behavior follows a normal fluidic performance. In terms of isobaric heat capacity, it was noticed that the addition of nanoparticles decreases the isobaric heat capacity proportionally. In addition to the experimental study, few correlations, along with an in-depth discussion, were proposed in order to better describe these nanocolloids properties. As a major conclusion, it may affirm that during this ample research, it was possible to get some in-depth information about the influence of nanoparticle type on the ionic liquids’ properties.