Activated bio-adsorbent for the removal of dyes in textile wastewater

Abstract

This invention proposes a bio-adsorbent based on black cumin seeds, effective for treating industrial textile wastewater. The black cumin seeds are washed with ultrapure water and air-dried for 12 hours, followed by a further drying step at a temperature of 50 °C for 24 hours. The dried seeds are then ground into a powder with a particle size of 600 µm. The chemical activation of this bioadsorbent is achieved by placing 10% of the powder in a 1M NaOH solution for one hour until the pH reaches 13. Once activated, the black cumin powder is washed several times with ultrapure water until the pH reaches 7, then dried at 50°C for 24 hours. The treatment of textile wastewater is carried out by batch adsorption of the target dye onto the activated black cumin.