Influence of the prepared activated carbon on cellulose acetate for malachite green dye removal from aqueous solution

Abstract

Guava (Psidium guajava) seeds were used for the preparation of activated carbon (AC) activated using zinc chloride (GCZ36), phosphoric acid (GCH36), potassium hydroxide (GCK36), and one other sample was prepared without activation (GC36), carbonized for 3 h at 600 °C. They were added to cellulose acetate to form hybrid membranes (Ms) using the phase inversion technique. The prepared AC was characterized by % ash content, % weight loss on drying, nitrogen adsorption isotherm, TEM, and XRD. FTIR and SEM were used for the ACs and Ms. GCK36 sample exhibited a higher surface area (905.27 m2/g) and total pore volume (0.5360 mL/g). The hybrid membranes were used to remove malachite green dye (MG) from wastewater. The effect of initial dye concentration, adsorbent dosage, pH, and contact time were studied. Pseudo-first-, pseudo-second-order, and intraparticle diffusion rate equations were proposed and the kinetic data were analyzed. Maximum adsorption capacity (31.82 mg/g) was achieved after 100 min, at pH 6 and 0.25% AC. The adsorption capacity of the cellulose acetate membrane was increased by 111.7% using the prepared activated carbon. The results indicated the chemisorption process and the adsorption was fitted to Langmuir > Freundlich > Tempkin due to R2 values.Graphical abstractSchematic diagram of preparation of a composite membrane of cellulose acetate and guava seeds activated carbon