Sustainable CO₂capture using activated carbon synthesized from sugar beet pulp: Role of carbonization and activation processes

Increasing levels of carbon dioxide (CO2) emissions, which significantly impact climate change, necessitate the development of effective carbon capture materials. This study investigates the potential of sugar beet pulp (SBP), an abundant agricultural waste material, as a raw material for producing activated carbon (AC) for CO2 adsorption. To our knowledge, this is the first comprehensive study specifically examining AC production from SBP for CO2 capture applications. Four activation methods-one-step chemical, physical, physicochemical, and two-step physicochemical were employed at carbonization temperatures of 500, 600, and 700 degrees C. The resulting ACs were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET) surface area analysis, and scanning electron microscopy (SEM). The two-step physicochemical activation process significantly increased the porosity and surface area of AC to 903.49 m2/ g. Among the tested conditions, AC produced at 700 degrees C with a 1:1 KOH/biomass ratio exhibited the highest CO2 adsorption capacity of 7.45 mmol/g. CO2 adsorption followed pseudo-second order (PSO) kinetics (qe = 128.77 mg/g, k2= 0.0045 g/mg.min, R2 = 0.9738), confirming chemisorption dominance. These findings demonstrate the effectiveness of activation techniques in enhancing the CO2 adsorption performance of AC obtained from SBP, highlighting its potential as an environmentally friendly, sustainable, and cost-effective adsorbent.