Calcified Shrimp Waste Supported Pd NPs as an Efficient Catalyst toward Benzene Destruction

Shrimp waste (SW) was calcified to CaCO3 and CaO with variant morphologies by simple calcination in air and used as efficient support for Pd NPs (<7 nm) in benzene oxidation. A combination of in situ diffuse reflectance fourier transform (DRIFT), hydrogen temperature-programmed reduction (H2-TPR), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM) were utilized to study the physicochemical properties and reveal the possible oxidation mechanism. The existence of both Pd2+ and Pd0 was essential for the oxidation activity. The 0.5-Pd/SW@600 catalyst with low activation energy (Ea = 50 kJ/mol) presented the best activity among the calcified SW supports. The observed performances correlated with the high Pd metal dispersion, the nature and morphology of the support, and the synergistic effect between the small Pd NPs and the SW support. In addition, the catalyst showed desirable stability and exceptional reusability, being highly resistant to CO2 and H2O vapor. Considering their green, high efficiency, but cost-effective nature, the biogenic Pd/SW catalysts are promising catalysts, and a million tons of SW can find application as support in benzene abatement. © 2019 American Chemical Society.