School of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin, 300384, P. R. China.
Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion, Tianjin, 300384, P. R. China.
Phys Chem Chem Phys. 2023 May 17;25(19):13716-13727. doi: 10.1039/d3cp00659j.
Using metal-free catalysts is widely recognized as a promising approach toward wastewater remediation because of the absence of metal leaching. However, the oxidation products involved in the oxidation process and the corresponding mechanisms are still not clear. In this work, N-doped carbocatalysts (CN) were fabricated using as-prepared g-CN and glucose solution, and the reactivity of the as-prepared catalysts was optimized by controlling calcination temperature. Correspondingly, increasing the calcination temperature promotes the catalytic oxidation of BPA. The positive correlations between the contents of pyridinic-N and graphitic-N and the values of BPA oxidation, as well as XPS analysis indicate the important roles of pyridinic-N and graphitic-N in BPA oxidation. According to the series of characterizations of the oxidation products and Raman analysis of the reaction process, the moderately activated persulfate (PS) on the CN catalyst is the predominant species in BPA oxidation and BPA can be oxidized to BPA polymers with high selectivity by H-abstraction under alkaline conditions. This work highlights the important role of the moderate activation of PS in the polymerization of phenolic contaminants under alkaline conditions, which enriches our understanding of the oxidation of aromatic contaminants by PS under alkaline conditions.
使用无金属催化剂被广泛认为是一种有前途的废水修复方法，因为它不存在金属浸出。然而，氧化过程中涉及的氧化产物及其相应的机制仍不清楚。在这项工作中，使用预先制备的 g-CN 和葡萄糖溶液制备了 N 掺杂碳催化剂（CN），并通过控制煅烧温度优化了所制备催化剂的反应性。相应地，升高煅烧温度可以促进 BPA 的催化氧化。BPA 氧化的 值与吡啶氮和石墨氮含量之间的正相关性，以及 XPS 分析表明吡啶氮和石墨氮在 BPA 氧化中起着重要作用。根据氧化产物的一系列表征和反应过程的拉曼分析，CN 催化剂上适度活化的过硫酸盐（PS）是 BPA 氧化中的主要物质，在碱性条件下，通过 H 抽提可以将 BPA 选择性地氧化为高选择性的 BPA 聚合物。这项工作强调了 PS 在碱性条件下聚合酚类污染物中的适度活化的重要作用，丰富了我们对 PS 在碱性条件下氧化芳香族污染物的认识。
