Optimization of basic dye removal by oil palm fibre-based activated carbon using response surface methodology

Area of Science:

• Materials Science
• Environmental Chemistry
• Chemical Engineering

Background:

• Activated carbon is a crucial adsorbent for water treatment.
• Developing sustainable and cost-effective activated carbon production methods is essential.
• Oil palm fiber presents a promising lignocellulosic precursor for activated carbon synthesis.

Purpose of the Study:

• To optimize the preparation of activated carbon from oil palm fiber using physiochemical activation.
• To investigate the impact of activation temperature, time, and KOH:char ratio on methylene blue (MB) uptake and carbon yield.
• To determine the adsorption capacity of the optimized activated carbon for MB.

Main Methods:

• Physiochemical activation involving potassium hydroxide (KOH) treatment and carbon dioxide (CO2) gasification.
• Central composite design (CCD) for experimental design and response surface methodology.
• Analysis of variance (ANOVA) to identify significant preparation variables.
• Langmuir isotherm modeling to assess adsorption capacity.

Main Results:

• Optimized preparation conditions: 862°C activation temperature, 1h activation time, and 3.1 KOH:char ratio.
• Optimum activated carbon achieved an MB uptake of 203.83 mg/g and a yield of 16.50%.
• Langmuir isotherm accurately described MB adsorption, yielding a maximum monolayer adsorption capacity of 400 mg/g at 30°C.

Conclusions:

• Oil palm fiber is a viable precursor for producing high-performance activated carbon.
• The physiochemical activation process effectively enhances the adsorptive properties of oil palm fiber-derived carbon.
• The optimized activated carbon demonstrates significant potential for removing methylene blue from aqueous solutions.