Comparative Study of the Effects of Various Activation Methods on the Desulfurization Performance of Petroleum Coke

ABSTRACT

In this study, we activated different samples of petroleum coke, an economical carbonaceous substance with great potential as an activated carbon material for the removal of SO₂, via six common methods, viz., hydrothermal, high-temperature, acid-based, alkali-based, H₂O₂-based and Cu²⁺-based treatment, and evaluated the desulfurization efficiency of each sample by investigating the dynamic SO₂ adsorption along with various relevant factors. We found that high-temperature activation modified the structure and chemical properties of the petroleum coke, leading to an initial desulfurization efficiency of 76.4%, with a specific surface area of 59.0 m² g^–1, whereas acid-based treatment increased the SO₂ removal rate to above 82%, producing a specific surface area as high as 247.7 m² g^–1. However, alkali-based treatment applied at a KOH/coke ratio of 4:1 achieved the best performance, with a desulfurization efficiency of 96.3% under the optimal conditions. Further comparison of the activated samples’ physicochemical properties revealed that both an optimized texture (due to the change in pore structure) and an increased number of active sites contributed to the enhanced desulfurization. Thus, our results demonstrate that activated petroleum coke exhibits several favorable properties that make it a promising sorbent for acidic SO₂ in industrial flue gas desulfurization.