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Catalytic peroxidation of acrylic acid from aqueous solution incorporated with highly active La_0.5Sr_0.5BO₃ (B=Cu, Fe and Ni) perovskite-like catalysts.

ABSTRACT: In the current study, catalytic behaviour of La_0.5Sr_0.5BO₃ (B=Cu, Fe and Ni) perovskite-like catalysts synthesized by sol-gel method were examined in catalytic peroxidation of acrylic acid as a model organic compound and further characterized by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) with energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The effect of various parameters such as catalyst dose, H₂O₂/acrylic acid molar ratio, temperature, pH and initial acrylic acid concentration on acrylic acid and COD removal was studied. The maximum acrylic acid and COD removal of 86.79% and 71.57% were observed at optimum operating conditions (e.g., La_0.5Sr_0.5CuO₃ catalyst dose = 600 mg/L, stoichiometric molar ratio of H₂O₂/acrylic acid = 1.5, pH = 3, temperature 65 °C and reaction time = 3 h). The ROS scavenging studies were performed to identify in-situ generated reactive oxidant species, e.g., hydroxyl radicals (^•OH), superoxide radicals (O₂ ^•־) and singlet oxygen (¹O₂) and treated with their respective quencher during catalytic peroxidation of acrylic acid. Acrylic acid removal kinetics was performed by first order and Langmuir-Hinshelwood kinetic models. The plausible degradation mechanism was proposed based on intermediates identified by GC-MS analysis during catalytic peroxidation of acrylic acid.

SUBMITTER: Kumar A

PROVIDER: S-EPMC7721942 | biostudies-literature |

REPOSITORIES: biostudies-literature

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