Experimental investigations into viscosity, pH and electrical conductivity of nanofluid prepared from palm kernel fibre and a mixture of water and ethylene glycol

Abstract

Extensive research has been carried out on the synthesis and applications of nanofluid produced from metals, nonmetals and their oxides. However, little or no attention has been paid to bio-based nanoparticles. The need for the use of bio-based nanoparticles and bio-based nanofluids is imperative to mitigate over-dependence on toxic synthetic nanoparticles. This idea is also in line with renewable and sustainable developmental goals. Moreover, bio-based materials like palm kernel fibre (PKF) constitute environmental waste in some quarters and its conversion to useful products for engineering application will take a long time in solving environmental issues and health hazards. In this study, the top-down approach was used to synthesize nanoparticles from PKF using a ball-milling machine. The PKF nanoparticles with an average size of ∼40 nm were dispersed in an ethylene glycol (EG)/water (50:50) base fluid up to 0.5% of the volume fraction. The viscosity, pH and electrical conductivity of PKF-water and EG (50:50) were studied for temperature ranging from 10 to 60 • C. The results showed that the viscosity of the PKF-based nanofluid increases with an increase in volume fraction and decreases exponentially with an increase in the working temperature of the nanofluid. The pH and the electrical conductivity increased as the volume fraction of the PKF nanoparticle was increased from 0.1 to 0.5%. However, the pH decreased with an increase in the temperature while the electrical conductivity increased with an increase in the volume fraction. Since the notable theoretical models in the literature were unable to estimate the viscosity of the PKF-EG/water nanofluid, in the present case an empirical correlation based on dimensional analysis was proposed to estimate the viscosity of the PKF-EG/water nanofluids.

Experimental Exploration of Hybrid Nanofluids as Energy-Efficient Fluids in Solar and Thermal Energy Storage Applications

“…Presently, ionic base fluids are yet to be investigated concerning the HNFs application focus of this review. In addition, green base fluids and green HNFs under the auspices of green, efficient, and sustainable HNFs are futuristic experimental undertakings in this research direction as very few studies have been carried out on the thermophysical and convective properties [ 141 , 142 , 143 , 144 , 145 , 146 , 147 , 148 ].…”

Synthesis, characterization, physicochemical, and electrical properties of natural (bio) nanofluids

“…In the last few years, studies have emerged on investing in the properties of green nanofluids prepared from the powder form of plant species like banana fiber, mango bark, and palm kernel fiber. [18][19][20] Nevertheless, research on green nanofluids is in the early stages of progress. It is challenging to create them from non-toxic and sustainable resources since additional research is required to determine the suitability, sustainability, and accessibility of the resources.…”

“…At the same time, they compared the PG and water blend at the same proportions and found an increase in TiO 2 properties by 12.6% and in SiO 2 properties by 7.2%. In the last few years, studies have emerged on investing in the properties of green nanofluids prepared from the powder form of plant species like banana fiber, mango bark, and palm kernel fiber 18–20 …”

Electrical conductivity and pH modelling of magnesium oxide–ethylene glycol nanofluids

“…Thermal conductivity and viscosity of nanofluids have received good attention theoretically and experimentally in order to understand the underlying causes of the inconsistent enhancements [1][2][3][4][5][6]. Hong et al [7] showed that agglomeration formation is one of the underlying factors that affect the enhancement value of nanofluids.…”