Surface-catalyzed hydrolysis by pyrogenic carbonaceous matter and model polymers: An experimental and computational study on functional group and pore characteristics
Surface-catalyzed hydrolysis by pyrogenic carbonaceous matter and model polymers: An experimental and computational study on functional group and pore characteristics
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DOI：
10.1016/j.apcatb.2022.121877
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发表时间：
2022-09-09
影响因子：
22.1
通讯作者：
Xu，Wenqing
中科院分区：
文献类型：
--
作者：
Li，Zhao;Jorn，Ryan;Xu，Wenqing
我们使用了一个聚合物网络来了解热解碳质(PCM；例如，活性碳)的什么性质赋予其反应性，我们以下将其称为类PCM聚合物(PLP)。这种方法使我们能够以2，4，6-三硝基甲苯(TNT)为模型污染物来描述官能团的作用和微孔特征。通过交叉偶联化学合成了6种具有特定官能度(-OH、-NH2、-N(CH3)2或-N(CH3)3+)和孔特征(中孔、微孔)的PLP。结果表明，PCM官能团通过以下方式催化反应：(1)作为弱碱(-OH，-NH2)攻击TNT，或(2)在PCM表面(-N(CH3)3+)附近积累OH-。此外，还监测了TNT的水解率、pH和共离子效应以及产物。与介孔聚合物相比，微孔PLP加速了TNT的衰减，分子动力学模拟结果进一步支持了这一点。我们还证明了季铵盐改性的活性碳促进了TNT的水解。这些发现对污染物减排和催化剂设计具有广泛的指导意义。
We employed a polymer network to understand what properties of pyrogenic carbonaceous matter (PCM;e.g., activated carbon) confer its reactivity, which we hereinafter referred to as PCM-like polymers (PLP). This approach allows us to delineate the role of functional groups and micropore characteristics using 2,4,6-trinitrotoluene (TNT) as a model contaminant. Six PLP were synthesized via cross-coupling chemistry with specific functionality (-OH, -NH2, -N(CH3)2, or -N(CH3)3+) and pore characteristics (mesopore, micropore). Results suggest that PCM functionality catalyzed the reaction by: (1) serving as a weak base (-OH, -NH2) to attack TNT, or (2) accumulating OH-near PCM surfaces (-N(CH3)3+). Additionally, TNT hydrolysis rates, pH and co-ion effects, and products were monitored. Microporous PLP accelerated TNT decay compared to its mesoporous counterpart, as further supported by molecular dynamics modeling results. We also demonstrated that quaternary ammonium-modified activated carbon enhanced TNT hydrolysis. These findings have broad implications for pollutant abatement and catalyst design.