Amphiphilic carbon nanotubes for catalytic wet peroxide oxidation of 4-nitrophenol Conference Paper uri icon

abstract

  • Carbon nanotubes (CNTs) were synthesized via chemical vapor deposition (CVD) over an AlCoFeO4 catalyst by a sequential feed of ethylene (E, as carbon source) and acetonitrile (A, as nitrogen source). The resulting samples were noted E20 (hydrophobic), E10A10 (amphiphilic), and A20 (hydrophilic), the number referring to the feed time (minutes) of each precursor, as reported elsewhere1. These materials were tested in the catalytic wet peroxide oxidation (CWPO) of 4-nitrophenol (4-NP). The reaction was monitored by HPLC (to determine the concentration of 4-NP and respective intermediates), TOC analyzer, and UV-vis spectrophotometry (to quantify H2O2) (Figure 1). After 8 h of reaction, A20 led to the highest consumption of H2O2 (90%), followed by E10A10 (61%) and E20 (52%). On the other hand, the highest degradation of 4-NP was observed with the amphiphilic E10A10 material (98%) followed by E20 (95%), whereas A20 only led to a removal of 69%. Similar behavior was found when analyzing the formation of reaction intermediates (data not shown), i.e., while A20 resulted in the accumulation of 4-nitrocatechol (4-NTC) and hydroquinone (HQ) E10A10 and E20 led to the total conversion of formed 4-NTC and HQ. This resulted in a lower TOC removal for A20 (37%) than to E10A10 and E20 (53%). Therefore, the amphiphilic E10A10 material is a promising catalyst for the CWPO of 4-NP.
  • This work was financially supported by project "PLASTIC_TO_FUEL&MAT – Upcycling Waste Plastics into Fuel and Carbon Nanomaterials" (PTDC/EQU-EQU/31439/2017), Base Funding - UIDB/50020/2020 of the Associate Laboratory LSRE-LCM - funded by national funds through FCT/MCTES (PIDDAC), and CIMO (UIDB/00690/2020) through FEDER under Program PT2020. Fernanda F. Roman acknowledges the funding by FCT, Foundation for Science and Technology, and FSE, European Social Fund, through the individual research grant SFRH/BD/143224/2019

publication date

  • January 1, 2021