Wollastonite (CaSiO<sub>3</sub>)-based Composite Particles for Synthetic Food Dyes (Brilliant Blue) Removal in Aquatic Media: Synthesis, Characterization and Kinetic study
Lusi Ernawati, Ruri Agung Wahyuono, Andromeda Dwi Laksono, Andriati Ningrum, Kurnia Handayani, Audi Sabrina
Abstract
Abstract We report a facile and environmentally friendly solid-state method to prepare mesoporous wollastonite (calcium silicate, CaSiO 3 ) based composite adsorbent from chicken eggshells and SiO 2 powder as starting materials for food dyes removal, i.e. brilliant blue. The CaSiO 3 particles were prepared using CaCO 3 /SiO 2 molar ratio of 1:5 and 2:5 and calcined at 1100°C. The physicochemical properties of adsorbent were characterized by SEM-EDX, XRD, BET-BJH, and FTIR analysis whilst the adsorbent performance was assessed for 100 ppm aqueous brilliant blue removal. The obtained CaSiO 3 shows single-phase hexagonal structure and the morphology was in irregular shape as revealed by scanning electron micrograph. In addition, the CaSiO 3 adsorbent shows specific surface area of 3.053 m 2 g −1 and a small pore diameter of 1.52 nm. The dye removal test indicates that maximum adsorption capacity of the dye molecules onto CaSiO 3 particles is approximately 173 mg g-1. The adsorption kinetics fit well with the pseudo-second order model while the adsorption equilibrium fits best the Langmuir model. In general, the prepared CaSiO 3 composite here is promising for dye removal in contaminated aqueous solution.