Mesoporous CeO₂ Catalyst Synthesized by Using Cellulose as Template for the Ozonation of Phenol

ABSTRACT

Mesoporous CeO₂ was synthesized by a sol-gel method using the biological renewable microcrystalline cellulose (MCC) as the template and Ce(NO₃)₃•6H₂O as the precursor of CeO₂. XRD, TEM, N₂ adsorption–desorption, and XPS were used for mesoporous CeO₂ characterization. The results show that CeO₂ nano-particles possess an average size of 7 ~ 10 nm, and specific area of CeO₂ synthesized with MCC template is approximately 5.5 times higher than CeO₂ synthesized without MCC. The ozonation catalyzed by CeO₂-T (with MCC) could remove 91.7% of phenol compared to 51.6% for single ozonation and 68.3% for CeO₂-W (without MCC) catalyzed ozonation. The COD removal efficiency is significantly higher for ozonation with CeO₂-T (69.2%) than that of CeO₂-W (49.5%) or ozonation alone (21.0%). The good performance of CeO₂-T is attributed to the high specific area and Ce(III)/Ce(IV) redox couple. During catalytic ozonation, the activation energy of catalytic ozonation (20.7 kJ mol⁻¹) is much lower than that of single ozonation (54.7 kJ mol⁻¹).

Graphical Abstract

KEYWORDS:

• Activation energy
• catalytic ozonation
• hydroxy radical
• mesoporous ceo₂
• microcrystalline cellulose
• phenol

Highlights

1. Using microcrystalline cellulose as template for preparing mesoporous CeO₂-T.

2. CeO₂-T has an excellent catalytic activity for ozonation of phenol.

3. High specific area and Ce(III)/Ce(IV) redox couple of CeO₂-T help to mineralize phenol.

Acknowledgments

The authors sincerely thank Changchun Institute of Applied Chemistry in Chinese Academy of Science for the detection and analysis of TEM, N₂ adsorption-desorption, and XPS.

Additional information

Funding

This research was supported by the Key Project in the National Science & Technology Pillar Program during the Twelfth Five-year Plan Period (2015BAB01B04), the Science and Technology Development Plan Project of Jilin Province (No.20150519020JH) and the National Natural Science Foundation of China (51378232) for their financial supports.