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Tuning the Acidity of Pt/ CNTs Catalysts for Hydrodeoxygenation of Diphenyl Ether
Published on: August 17, 2019
Pt-catalyzed ozonation of aqueous phenol solution using high-gravity rotating packed bed
Chia-Chi Chang1, Chun-Yu Chiu, Ching-Yuan Chang
1Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Taiwan.
Journal of Hazardous Materials
|April 28, 2009
Summary
This study demonstrates that a high-gravity rotating packed bed reactor effectively decomposes phenol using catalytic ozonation. Combining UV light with platinum catalyst significantly enhances phenol degradation efficiency.
Area of Science:
- Environmental Chemistry
- Chemical Engineering
- Advanced Oxidation Processes
Background:
- Phenol is a common pollutant in industrial wastewater.
- Conventional treatment methods often struggle with efficient phenol removal.
- Advanced Oxidation Processes (AOPs) offer promising solutions for pollutant degradation.
Purpose of the Study:
- To investigate the efficacy of a high-gravity rotating packed bed (HGRPB) reactor for phenol decomposition.
- To evaluate different combinations of AOPs, including catalytic ozonation and UV irradiation, within the HGRPB system.
- To assess the impact of platinum-based catalysts and UV light on phenol degradation efficiency.
Main Methods:
- A semi-batch HGRPB system integrating a rotating packed bed (RPB) and a photo-reactor (PR) was employed.
- Platinum-containing catalyst (Pt/γ-Al2O3) and activated alumina (γ-Al2O3) were packed in the RPB.
- UV irradiation (200-280 nm) was utilized in the PR to enhance ozone decomposition.
- Various configurations were tested: HG-OZ, HG-Cat-OZ, HG-UV-OZ, and HG-Cat-UV-OZ.
Main Results:
- HG-UV-OZ achieved 54% total organic compound (TOC) decomposition at 1200 mg L⁻¹ ozone dosage, significantly higher than HG-OZ (24%).
- After 80 min, HG-UV-OZ reached 94% TOC removal, while HG-OZ achieved 82%.
- HG-Cat-OZ with 77g catalyst reached 90% TOC removal at 4800 mg L⁻¹ ozone dosage; Pt/γ-Al2O3 and UV significantly enhanced degradation, while γ-Al2O3 had minimal effect.
Conclusions:
- The HGRPB reactor is highly effective for phenol decomposition via catalytic ozonation.
- The combination of UV irradiation and platinum catalyst in the HGRPB system significantly boosts phenol degradation efficiency.
- The HGRPB system offers a superior gas-liquid mass transfer, enhancing the performance of AOPs for wastewater treatment.
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