Development of sulphur-doped carbon monolith derived from phenol-formaldehyde resin for fixed bed CO2 adsorption

In this work, nanocasting technique (phenol-formaldehyde resin as a carbon source) followed by chemical activation (sodium thiosulphate) have been used for the synthesis of S-doped carbon monolith. The morphological and surface properties were explored by using various characterization techniques. The surface area of 510 m2 g−1was found for the nanocasted carbon monolith synthesized under carbonization temperature of 900 °C. Sulphur content of the S-doped monolith (PFC-S) was found to be 2.89 wt%. Relevant for the real applications in the power plants, the fixed bed CO2 adsorption–desorption system was taken in use to examine adsorption studies of the monoliths. Maximum CO2uptake (1.25 mmol g−1) was found for the PFC-S monolith at 30 °C due to the various basic oxygen and sulphur functionalities present on its surface. Also, the monoliths have excellent capability to regenerate several times for the adsorption–desorption process. In the kinetic studies, the fractional order model was fitted best as compared to the other models, whereas, Temkin model showed good fitting in the isotherm studies.