Scholarlink

<p>This study quantitatively investigated the inhibitory effect of cysteine (CYS), an eco-friendly compound, on the degradation efficiency of trichloroethylene (TCE) in heterogeneous nano zero-valent iron (nZVI)-activated percarbonate (SPC) systems. The addition of CYS to the nZVI/SPC system reduced the TCE oxidation capability from 90.5% to 81.3%, whereas Fe(II)/SPC exhibited an increase in oxidation capability. Increasing CYS concentration from 5 to 20&#xa0;mM decreased TCE degradation from 86.7% to 68.5%. The presence of thiol (-SH) groups in CYS led to the formation of disulfide bonds with iron nanoparticles, effectively blocking their surface and inhibiting their interactions with contaminants. Theoretical calculations using first principles confirmed that CYS had the highest reaction energy barrier with •OH (0.50&#xa0;eV), indicating a minimal impact on TCE degradation efficiency. Furthermore, -SH acted as an antioxidant, scavenging free radicals and limiting the participation of nZVI in the Fenton-like oxidation process. The conversion of CYS to cystine was observed, and FTIR analysis revealed modifications in the nZVI structure due to -SH group reactions. The disappearance of specific peaks indicated the blockage of active surface sites on nZVI, further inhibiting TCE degradation. These computational discoveries substantiate the experimental findings and provide additional insights into the interactions of SH-containing organics with nZVI in groundwater remediation technologies.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Unraveling the Inhibitory Effects of Cysteine on Nanoscale Zero-Valent Iron Activated Percarbonate Systems for Contaminant Degradation: Experimental and Theoretical Study

  • 期刊论文

  • 发表日期：

    2025年6月11日

查看全文
  • Yawen Li,
  • Guoyang Ma,
  • Shaohong Xu,
  • Usman Farooq

摘要

This study quantitatively investigated the inhibitory effect of cysteine (CYS), an eco-friendly compound, on the degradation efficiency of trichloroethylene (TCE) in heterogeneous nano zero-valent iron (nZVI)-activated percarbonate (SPC) systems. The addition of CYS to the nZVI/SPC system reduced the TCE oxidation capability from 90.5% to 81.3%, whereas Fe(II)/SPC exhibited an increase in oxidation capability. Increasing CYS concentration from 5 to 20 mM decreased TCE degradation from 86.7% to 68.5%. The presence of thiol (-SH) groups in CYS led to the formation of disulfide bonds with iron nanoparticles, effectively blocking their surface and inhibiting their interactions with contaminants. Theoretical calculations using first principles confirmed that CYS had the highest reaction energy barrier with •OH (0.50 eV), indicating a minimal impact on TCE degradation efficiency. Furthermore, -SH acted as an antioxidant, scavenging free radicals and limiting the participation of nZVI in the Fenton-like oxidation process. The conversion of CYS to cystine was observed, and FTIR analysis revealed modifications in the nZVI structure due to -SH group reactions. The disappearance of specific peaks indicated the blockage of active surface sites on nZVI, further inhibiting TCE degradation. These computational discoveries substantiate the experimental findings and provide additional insights into the interactions of SH-containing organics with nZVI in groundwater remediation technologies.