Carbon capture by porous biocarbon monoliths : dynamic adsorption performance and process evaluation using breakthrough experiments
Shojaei Barjouei, Pejman (2026)
Diplomityö
2026
School of Engineering Science, Kemiantekniikka
Kaikki oikeudet pidätetään.
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi-fe2026061469062
https://urn.fi/URN:NBN:fi-fe2026061469062
Tiivistelmä
In the realm of carbon dioxide capture, the discussion surrounding solid adsorbents as an energy-efficient alternative to conventional solvent separation processes has gained momentum. In this thesis, PAN-based porous biocarbon monoliths were investigated as new solid adsorbents for CO2 capture in different aspects, focusing on dynamic breakthrough analysis. The equilibrium adsorption behavior of the PAN-based porous biocarbon monoliths has been evaluated for temperature and pressure effects, concentration dependence, and cyclic stability under controlled operating conditions using a mixSorb SHP dynamic sorption analyzer.
Equilibrium CO2 adsorption isotherms were measured at 25, 50, and 75 °C, in which the adsorption capacity of the sample reached 5.957 mmol/g at 25 °C, 4.998 mmol/g at 50 °C, and 4.056 mmol/g at 75 °C, confirming the exothermic behavior of CO₂ adsorption. Moreover, different isotherm models were evaluated, and the Freundlich model provided the best fit, with determination coefficients above 0.99.
Breakthrough dynamic experiments for the variables of temperature, pressure, and concentration effects illustrated that increasing temperature reduced the adsorption capacity, while increasing pressure increased the capacity. In this regard, in the pressure swing adsorption (PSA) test, the adsorption capacity increased from 1.234 mmol/g at 1.2 bar to 3.060 mmol/g at 5 bar. PAN-based porous biocarbon monoliths showed good performance during the cycle stability test, with a slight decrease in adsorption capacity, indicating a promising adsorbent for practical CO₂ capture applications.
Equilibrium CO2 adsorption isotherms were measured at 25, 50, and 75 °C, in which the adsorption capacity of the sample reached 5.957 mmol/g at 25 °C, 4.998 mmol/g at 50 °C, and 4.056 mmol/g at 75 °C, confirming the exothermic behavior of CO₂ adsorption. Moreover, different isotherm models were evaluated, and the Freundlich model provided the best fit, with determination coefficients above 0.99.
Breakthrough dynamic experiments for the variables of temperature, pressure, and concentration effects illustrated that increasing temperature reduced the adsorption capacity, while increasing pressure increased the capacity. In this regard, in the pressure swing adsorption (PSA) test, the adsorption capacity increased from 1.234 mmol/g at 1.2 bar to 3.060 mmol/g at 5 bar. PAN-based porous biocarbon monoliths showed good performance during the cycle stability test, with a slight decrease in adsorption capacity, indicating a promising adsorbent for practical CO₂ capture applications.