Han Ruirui, Fang Yingsen, Sun Ping, Xie Kai, Zhai Zhicai, Liu Hongxia, Liu Hui
College of Advanced Materials and Engineering, Jiaxing Nanhu University, Jiaxing 314001, China.
College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing 314001, China.
Nanomaterials (Basel). 2021 Sep 2;11(9):2288. doi: 10.3390/nano11092288.
In this paper, using rice straw as a raw material and urea as a nitrogen precursor, a composite catalyst (a nitrogen-doped rice straw biochar at the pyrolysis temperature of 800 °C, recorded as NRSBC800) was synthesized by one-step pyrolysis. NRSBC800 was then characterized using XPS, BET, TEM and other technologies, and its catalytic performance as an activator for permonosulfate (PMS) to degrade acid orange 7 (AO7) was studied. The results show that the introduction of N-doping significantly improved the catalytic performance of NRSBC800. The NRSBC800/PMS oxidation system could fully degrade AO7 within 30 min, with the reaction rate constant (2.1 × 10 min) being 38 times that of RSBC800 (5.5 × 10 min). Moreover, NRSBC800 not only had better catalytic performance than traditional metal oxides (CoO and FeO) and carbon nanomaterial (CNT) but also received less impact from environmental water factors (such as anions and humic acids) during the catalytic degradation process. In addition, a quenching test and electron paramagnetic resonance (EPR) research both indicated that AO7 degradation relied mainly on non-free radical oxidation (primarily singlet oxygen (O)). A recycling experiment further demonstrated NRSBC800's high stability after recycling three times.
本文以稻草为原料，尿素为氮前驱体，通过一步热解合成了一种复合催化剂（800℃热解温度下的氮掺杂稻草生物炭，记为NRSBC800）。然后利用XPS、BET、TEM等技术对NRSBC800进行了表征，并研究了其作为过一硫酸盐（PMS）活化剂降解酸性橙7（AO7）的催化性能。结果表明，氮掺杂的引入显著提高了NRSBC800的催化性能。NRSBC800/PMS氧化体系能在30分钟内完全降解AO7，反应速率常数（2.1×10 分钟）是RSBC800（5.5×10分钟）的38倍。此外，NRSBC800不仅比传统金属氧化物（CoO和FeO）和碳纳米材料（CNT）具有更好的催化性能，而且在催化降解过程中受环境水因素（如阴离子和腐殖酸）的影响较小。此外，猝灭试验和电子顺磁共振（EPR）研究均表明，AO7的降解主要依赖于非自由基氧化（主要是单线态氧（O））。回收实验进一步证明了NRSBC800在三次回收后的高稳定性。
