Abstract
This experimental investigation focuses on the effect of Cetrimonium bromide (CTAB) surfactant on different categories of nanolubricant in terms of stability and thermal conductivity. There are six categories, four as mono nanolubricant listed as Graphene (GR), GR with CTAB, Functionalised Multi-wall carbon nanotube (FMWCNT), FMWCNT with CTAB, and another two categories as hybrid nanolubricant listed as a hybrid, and hybrid with CTAB nanolubricants. High-grade polyester SL68 Oil is used as a lubricant in this experimental study. Zeta potential measurement, Ultraviolet-visible (UV-vis) spectroscopy, and visual observation by backlighted light emitting diode (LED) stage are used to evaluate and obtain the nanolubricant stability changes. KD2 Pro Thermal Properties Analyzer is used in thermal conductivity analysis. The study revealed hugely different ratios for the optimum CTAB amount of the studied categories. The best ratio for GR is 1:1, whereas the best ratio for FMWCNT is 1:8. In addition, improvement between 2% and 7% in thermal conductivity is revealed compared to pure oil.