OPTIMIZATION OF FUNCTIONALIZED RICE HUSK BIOCHAR WITH β-CYCLODEXTRIN FOR THE ADSORPTION OF CARBAZOLE

• Main Author: AZMAN, NUR AZZYYATI
• Format: Thesis
• Language: English; English; English
• Published: 2024
• Subjects: T175-178 Industrial research. Research and development
• Online Access: http://eprints.uthm.edu.my/12640/

Carbazole (CBZ) is a heterocyclic aromatic hydrocarbon that is persistent in the wastewater and has carcinogenic properties. Adsorption has been a widely opted remediation for environmental pollutants because of its simple application. In this study, functionalized rice husk biochar with beta-cyclodextrin (RHB-CD) was prepared as an effective adsorbent for carbazole adsorption. The preparation was optimized by Response Surface Methodology (RSM) using Box-Behnken Design (BBD) and optimized RHB-CD was characterised using Scanning Electron Microscopy with Energy Dispersive X-Ray (SEM-EDX), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), and particle size analyser. The parameters including rice husk biochar (RHB) mass (5–10) g, β-cyclodextrin (β-CD) concentration (1–5) %w/v, and sonication time (1–5) mins with two responses of removal rate (%) and adsorption capacity (mg/g) have been performed. Accordingly, the RHB mass of 6.50 g, β-CD concentration of 1 % w/v, and sonication time of 5 mins obtained from the BBD was validated. Batch adsorption study, together with kinetic and isotherm adsorption study was carried out. Using optimal RHB-CD, adsorption capacity of 392.96 mg/g carbazole was obtained at reaction conditions of RHB-CD mass of 10 mg, pH 3, 70 mins reaction time at 25℃ on 250 rpm. The kinetic uptake results were well described by the pseudo-second order kinetic model compared to the pseudo-first order. The Temkin isotherm model showed a better fit than the Langmuir and Freundlich models. Therefore, the RHB-CD could be a promising adsorbent in removing CBZ from wastewater