Curcumin Dye Adsorption in Aqueous Solution by Carbon-based Date Palm Seed: Preparation, Characterization, and Isotherm Adsorption

Abstract

In this study, date-seed-based carbon was prepared and investigated for the adsorption process on the removal of curcumin dye in an aqueous solution. Carbon is prepared by carbonizing date palm seeds for 3 hours at a temperature of 250°C, followed by a grinding and sieving process. The carbon particles were then characterized using a Digital Microscope, sieve test, and Fourier transforms infrared analysis instrument. The adsorption test was carried out through batch experiments at constant pressure and room temperature. The adsorption results were then evaluated using ten adsorption isotherm models, including Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, Fowler-Guggenheim, Hill-Deboer, Jovanovic, Harkin-Jura, Flory-Huggins, and Halsey. Carbon-based adsorbent from date palm seed showed an adsorption capacity in the range of 38.759 mg/g with a suitable adsorption isotherm is Langmuir > Dubinin-Radushkevich > Jovanovic > Freundlich > Halsey. Based on the five best-fitted isotherms, the adsorption process runs normally, spontaneously, and favorably, confirming monolayer and multilayer formation occurs on heterogeneous surfaces. Then, the adsorption follows cooperative adsorption with chemical and physical interactions at one time. The research study presents findings on adsorbents synthesized by date palm seeds for water treatment and their potential applications as adsorbents.