Abstract

The focus of this research was on the catalytic reduction of nitrate to nitrogen gas for the water conservation. Zero-valent iron (Fe⁰) with bimetallic catalyst that carrier supported palladium (Pd) and copper (Cu) was innovatively applied in this study. First, XPS (X-ray photoelectron spectroscopy) analyses and experiments were conducted to study the mechanism of the catalytic reduction of nitrate. In the catalytic reaction, which is regarded as a stepwise process, Fe⁰ was the electron provider; Pd and Cu supported on carrier played indispensable but distinct roles. The kinetics suggested that the process was better reflected by first-order kinetics of the Langmuir-Hinshelwood model. Additionally, first-order kinetics of the catalytic reaction under the effect of catalysts with different carriers (SiO₂, silica gel, kaolin, diatomite, γ-Al₂O₃, graphene) were further studied. Pd-Cu/graphene catalyst showed higher catalytic performance compared with other catalysts.

摘要

这项研究的重点是将硝酸盐催化还原为氮气以节约用水。在这项研究中创新地应用了具有双金属催化剂的零价铁（Fe ⁰），其载有载体负载的钯（Pd）和铜（Cu）。首先，进行了XPS（X射线光电子能谱）分析和实验，以研究硝酸盐催化还原的机理。在被认为是逐步过程的催化反应中，Fe ⁰是电子提供者；载于载体上的钯和铜起着不可或缺的作用。动力学表明，该过程可以由Langmuir-Hinshelwood模型的一级动力学更好地反映。此外，具有不同的载流子的催化剂的作用下催化反应的一级动力学（SIO ₂，硅胶，高岭土，硅藻土，在γ-Al ₂ ö ₃，石墨烯）的进一步研究。与其他催化剂相比，Pd-Cu /石墨烯催化剂表现出更高的催化性能。