Spectral evidence of acetamiprid's thermal degradation products and mechanism

SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY(2023)

引用 3|浏览5
暂无评分
摘要
Herein we unequivocally identify the mechanism of zeolite-catalysed thermal degradation of pesticide, employing Fourier-transform infrared spectroscopy (FTIR), Raman and mass spectrometry following temperature decomposition (TPDe/MS). We demonstrate that Y zeolite can effectively adsorb a significant amount of acet-amiprid both in a single trial (168 mg/g) and in 10 cycles (1249 mg/g) with intermittent thermal regeneration at 300 C-degrees. Sectional vibrational analysis of acetamiprid two-stage thermal degradation is performed for pristine and supported pesticide. The acetamiprid Raman spectral changes appear at 200(degrees) C, while partial carbonization occurs at 250 C-degrees. The gradual disappearance of the FTIR bands of acetamiprid is seen up to 270 C-degrees when two Raman signature bands for carbonised material emerged. The TPDe/MS profiles reveal the evolution of mass fragments -in the first step, cleavage of the C-C bond occurs between the aromatic core of the molecule and its tail-end, followed by cleavage of the C-N bond. The mechanism of adsorbed acetamiprid degradation follows the same step, at significantly lower temperatures, as the process is catalysed by the interaction of acetamiprid nitrogens and zeolite support. Reduced temperature degradation allows for a quick recovery process that leaves 65% efficacy after 10 cycles. After numerous cycles of recovery, a subsequent one-time heat treatment at 700 C-degrees completely restores initial efficacy. The efficient adsorption, novel details on degradation mechanism and ease of regeneration procedure place the Y zeolite at the forefront of future all-encompassing environmental solutions.
更多
查看译文
关键词
Y zeolite,Acetamiprid,Thermal degradation,Regeneration
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要