Starch nanocomposite containing hydroxyapatite and eggshell for absorbing methylene blue dye from aqueous solution

Today, polymer nanocomposites (NCs) have become important as suitable candidates for nano absorbents due to their simplicity and cheapness. This research investigated a nano absorbent based on starch nanocomposite containing hydroxyapatite (HA) and eggshell inspired by nature to absorb methylene blue (MB) as a toxic cationic dye from aqueous solution. The effect of temperature, pH, and the ratio of hydroxyapatite and eggshell absorbent on the amount of absorption after immersion in an aqueous medium was measured. The samples were identified by the UV-Vis spectrophotometer, scanning electron microscope (SEM), X-ray energy dispersive spectrometry (EDS), Fourier transform infrared (FTIR), X-ray diffraction (XRD), and BET analysis. Based on the results, the biological nanocomposite of starch-containing 0.125 g hydroxyapatite and eggshell, inspired by nature, has the highest absorption (88%) of methylene blue dye from the aqueous solution quickly. Increasing temperature, increasing pH, and decreasing the amount of nano absorbent increased the absorption of methylene blue dye from the aqueous solution. The results show that starch nanocomposite containing hydroxyapatite and eggshell can absorb methylene blue dye and have good potential for various applications, especially in medical and industrial fields.