Synthesis of calcium vanadate nanoparticles as a catalyst for dry sulphur dioxide desulfurization

Chronic health and ecological issues stemming from sulfur dioxide (SO₂) emissions due to fossil fuel combustion necessitate the development of more efficient and cost-effective scrubbing methods beyond conventional wet flue gas desulfurization (WFGD). This study explored the synthesis of a calcium vanadium-based nanocomposite (CaV₂O₆) using vanadium pentoxide (V₂O₅) waste and calcium nitrate (Ca(NO₃)₂) as precursors, intended for application as a catalytic adsorbent in dry desulfurization systems. The primary objective was to enhance SO₂ selectivity and catalytic activity by refining the sorbent’s morphological properties to improve thermal stability and redox performance. The formulation approach involved a sol-gel process, rapid thermal treatment, and subsequent hydrogen reduction. A central composite design (CCD) was employed to optimize synthesis parameters, including reaction temperatures ranging from 700 to 1000 °C, reaction times from 1-3 hours, and a V₂O₅:Ca(NO₃)₂ molar ratio of 0.3-1.0. The physicochemical properties of the CaV₂O₆ material were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) surface area analysis. SEM revealed a porous nanosheet morphology, while XRD confirmed the formation of an orthorhombic CaV₂O₆ phase. BET analysis showed an average surface area of 25.340 m²/g, representing a 40.6% increase compared to a conventional Ca(OH)₂ sorbent (18.019 m²/g). The developed material suggests that the laboratory-scale synthesis protocol is capable of replacing costly dry flue gas desulfurization reagents with those derived from sustainable precursors.