Acta Chemica Malaysia (ACMY)

This study uses graphite, eggshell, and snail shell as friction modifiers in the formulation of bio-hydraulic fluids from palm kernel oil through experimentation and optimization using Response Surface Methodology (RSM). The analyzed samples of graphite, eggshell, and snail shell were characterized using XRD. The biohydraulic fluids with graphite, eggshell, and snail shell were optimized using RSM. Sample compositions reveal that graphite contains silicon oxide (30.1%), eggshell contains silicon oxide (10.41%), and snail shell contains silicon oxide (23.4%), indicating that eggshell and snail shell can compete favorably with graphite. FT-IR spectra of the bio-hydraulic fluids with graphite, eggshell, and snail shell reveal functional groups, each having double bond structures and heteroatoms. The optimum conditions for bio-hydraulic fluid viscosity with graphite, eggshell, and snail shell are glycerin/methanol ratio of 20, eggshell dosage of 0.6, and temperature of 60 °C, yielding viscosities of 36.36 cP, 33.61 cP, and 35.21 cP, respectively. The quadratic method describes the relationship between the response (viscosity) and the considered factors adequately. The physicochemical properties of the bio-hydraulic fluids with graphite, eggshell, and snail shell show pour points of-43.9 °C,-40.6 °C, and-39.5 °C, flash points of 253 °C, 245 °C, and 242 °C, viscosities of 36.53 cP, 33.79 cP, and 35.36 cP, and BOD values of 8.51 ppm, 8.12 ppm, and 8.30 ppm, respectively. These values indicate that the bio-hydraulic fluids are suitable for various hydraulic industrial applications. Graphite, eggshell, and snail shell were established as effective friction modifiers in bio-hydraulic fluid formulation.