Nuclear chemistry

Catalysis

Adsorption

Engineering

Enthalpy

Chemical engineering

Saturation (graph theory)

Activated carbon

BET theory

Porosity

Physical chemistry

Thermodynamics

Physics

Organic chemistry

Mathematics

Langmuir

Aqueous solution

Combinatorics

Chemistry

Specific surface area

Activation energy

Chemical Engineering Journal

Activated carbons were synthesized by FeCl3-activation of Tara gum at different temperatures (400–1000 °C). The activating agent and the precursor were physically mixed at different ratios (r = FeCl3:precursor, 0.5–3.0 wt). At r = 2 and 800 °C the most developed porosity was achieved, with a BET surface area of 1680 m2·g−1 and a pore volume near 1 cm3·g−1, corresponding mostly to micropores (≈75%). The carbons were fully characterized and tested for the aqueous-phase adsorption of antipyrine, used as model emerging pollutant. The kinetic curves and adsorption isotherms at 20, 40 and 60 °C were obtained, which fitted well to hyperbolic and Langmuir equations, respectively. At 20 °C, the saturation adsorption capacity was around 275 mg·g−1 AC. The free energy of adsorption varied from −40.2 to −35.7 kJ·mol−1, while values close to −3 kJ·mol−1 and 112 J·mol−1·K−1, were obtained for the enthalpy and entropy of adsorption, respectively.

Adsorption of antipyrine by activated carbons from FeCl3-activation of Tara gum