Peanut shell material was used as a precursor for the production of
medicinal activated carbon via physical activationwith CO2. The characteristics
of the resulting carbon, as well as its MB adsorption kinetics,
were investigated. An MB uptake of 225.8 mg g−1 and a phenazone uptake
of 421.5 mg g−1, with a yield of 26.15%, were obtained at the optimumconditions:
an activation time of 5 h and an activation temperature
of 900 °C. In addition, the optimised samples exhibited high surface area
and well-developed porosity with a BET surface area of 1060 m2 g−1
and a total pore volume of 0.8021 cm3 g−1. The kinetic process of
MB adsorption was better described by a pseudo-second-order kinetic
model. Ionisable groups (carboxyls and hydroxyls) were able to interact
with protons and metal or positive dye ions; therefore, the adsorption
capacity of the activated carbon was dependent not only on the surface
area but also on the interactions of positive ions. The quality of the prepared
activated carbon met the USP and BP standards, which indicates
that peanut shells have high potential economic value for the production
of medicinal activated carbon.