Highly Efficient Multisubstrate Agricultural Waste-Derived Activated Carbon for Enhanced CO₂ Capture

Area of Science:

• Materials Science
• Environmental Chemistry
• Chemical Engineering

Background:

• Activated carbon (AC) from agricultural waste is a potential low-cost adsorbent but suffers from low efficiency and limited CO2 adsorption.
• Challenges include seasonal scarcity, poor stability, low surface area, and inadequate performance for large-scale applications.

Purpose of the Study:

• To develop a high-performance composite activated carbon (CAC) from a blend of agricultural wastes for enhanced CO2 adsorption.
• To optimize the production parameters of CAC for superior CO2 capture efficiency.

Main Methods:

• Composite activated carbon (CAC) was synthesized using controlled carbonization and chemical activation (Na2CO3, KOH, NaOH) of peanut shell, coffee husk, corn cob, and banana peel.
• Optimization of impregnation ratio, time, carbonization temperature, and duration.
• Characterization using XRD, SEM, EDS, Raman spectroscopy, N2 adsorption-desorption, and iodine number analysis.

Main Results:

• Na2CO3-activated CAC exhibited superior surface area and textural properties for CO2 adsorption compared to KOH- and NaOH-activated materials.
• Optimized CAC achieved 96.2% CO2 removal efficiency and 8.86 wt% adsorption capacity, outperforming single-biomass AC.
• Enhanced performance attributed to high surface area, mesoporosity, and optimal pore width.

Conclusions:

• The developed composite activated carbon presents a promising, cost-effective strategy for CO2 emission mitigation.
• This adsorbent overcomes the limitations of traditional AC derived from single agricultural wastes.
• The study highlights a viable alternative to expensive and less effective CO2 capture materials.