Removal of malachite green dye in aqueous solution by Activated Custard apple (Annona Squamosa) Peel Powder

Abstract

In the present study Custard apple peel powder (CAPP), a fruit waste, was activated by carbonizing in a Muffle Furnace to improve its surface adsorption capacity and used as an adsorbent for removal of Malachite Green (MG) from aqueous solution. Carbonisation of the bioadsorbent plays a key role in efficient adsorption which is proved by surface analysis of the bioadsorbent by Scanning Electron Microscope before and after adsorption. The color removal performance of CAPP has been investigated using parameters such as initial dye concentration (10-40ppm), pH (3-7), time of contact (15-90 min) and adsorbent dosage (0.1-0.6 mg/50ml). Adsorption was favorable at slightly acidic condition and the maximum removal was obtained at pH 6. Percentage of dye removal was maximum when the contact time was 75 min(91.5%) and adsorbent dosage of 0.3mg/50ml (95.3%). The kinetic studies revealed that the kinetic data fitted well to the pseudo‐first‐order model. The isotherm study also indicated that MG adsorption on CAPP matched well with the Langmuir model rather than the Freundlich model. The results show that CAPP can be a promising alternate for the removal of MG from aqueous solutions and effluents.