Analisis Potensi Adsorben Berbahan Dasar Karboksimetil Selulosa dan GUAR GUM terhadap Penyerapan Metilen Biru Menggunakan Isoterm Adsorpsi Freundlich dan Langmuir

Abstract

The research on the adsorption capacity of methylene blue using adsorbents based on carboxymethyl cellulose (CMC) and guar gum has been conducted. This study aimed to determine the equilibrium time of methylene blue adsorption, evaluate the adsorption capacity of the adsorbent, and identify the appropriate isotherm model for the produced adsorbent. The adsorbent was prepared by blending CMC and guar gum, with aluminum sulfate octadecahydrate and boric acid added as cross-linking agents. The resulting adsorbents were characterized by WAC, degree of cross-linking, FTIR, and SEM. Dye adsorption was performed with time variations at intervals of 15 minutes, 30 minutes, 45 minutes, 60 minutes, and 75 minutes. The equilibrium time was found to be 45 minutes. Subsequent adsorption of methylene blue was carried out with concentration variations of 20 ppm, 40 ppm, 60 ppm, 80 ppm, and 100 ppm. The concentration of each methylene blue variation was determined using a UV-Visible spectrophotometer. The experimental results indicated that the CMC-GG-AL-AB adsorbent was effective in adsorbing methylene blue dye. The adsorption capacities at concentration variations of 20 ppm, 40 ppm, 60 ppm, 80 ppm, and 100 ppm were 3.7017 mg/g; 7.4113 mg/g; 10.9718 mg/g; 14.9653 mg/g; and 18.6531 mg/g, respectively. The higher the concentration of methylene blue dye, the higher the adsorption capacity of the produced adsorbents. In this study, the appropriate adsorption isotherm model was the Langmuir isotherm with an R2 value of 0.9912 and an obtained adsorption capacity of 158.73 mg/g.