Physical-Chemical Characterization of Different Carbon-Based Sorbents for Environmental Applications

Area of Science:

• Environmental Science
• Materials Science
• Chemical Engineering

Background:

• Biochar, a waste pyrolysis byproduct, is explored as a sustainable alternative to activated carbon for environmental remediation.
• Biochar exhibits high treatment efficiency in removing contaminants from water and gaseous emissions.
• Its utilization aligns with circular economy principles, promoting waste valorization.

Purpose of the Study:

• To conduct a detailed characterization of two biochars (RE-CHAR®, AMBIOTON®) and one activated carbon (CARBOSORB NC 1240®).
• To compare the physical and chemical properties of these carbonaceous materials.
• To evaluate the potential for biochar to substitute activated carbon in remediation applications.

Main Methods:

• Characterization techniques included particle size distribution, elemental analysis, pH, scanning electron microscopy, pore volume, specific surface area, and ionic exchange capacity.
• Comparative analysis of surface area, pore size distribution, and elemental composition.
• Evaluation of physical and chemical property variations based on feedstock and pyrolysis conditions.

Main Results:

• Activated carbon (CARBOSORB NC 1240®) exhibited a significantly higher specific surface area (1126.64 m²/g) compared to biochars RE-CHAR® (280.25 m²/g) and AMBIOTON® (256.23 m²/g).
• All materials were classified as mesoporous, with pore sizes ranging from 2 to 50 nm.
• Chemical composition showed similar C, H, and N content, but RE-CHAR® had a higher oxygen content (9.9%) than the others.

Conclusions:

• While activated carbon possesses a larger surface area, the mesoporous nature of both biochars and activated carbon suggests comparable potential in certain remediation applications.
• Differences in properties are attributed to feedstock and pyrolysis conditions, highlighting the need for tailored biochar production.
• Further research can explore specific contaminant removal efficiencies to fully assess biochar as an activated carbon alternative.