Ostwald Process Intensification by Catalytic Oxidation of Nitric Oxide

Area of Science:

• Chemical Engineering
• Catalysis
• Industrial Chemistry

Background:

• The Ostwald process is a cornerstone for industrial nitric acid (HNO3) production, vital for fertilizers.
• Despite optimization, opportunities for process intensification remain, particularly in NO to NO2 oxidation.
• Catalyzing this step can significantly improve overall efficiency.

Purpose of the Study:

• To investigate the catalytic activity of ruthenium supported on gamma-alumina (γ-Al2O3) for NO to NO2 oxidation.
• To evaluate the potential of this catalyst for intensifying the Ostwald process.
• To assess catalyst performance under industrially relevant conditions.

Main Methods:

• Wash-coating ruthenium and γ-Al2O3 onto a cordierite monolith.
• Testing the catalyst in a lab-scale setup with simulated industrial feed gas.
• Evaluating catalyst performance in a pilot plant at a commercial fertilizer facility.

Main Results:

• The Ru/γ-Al2O3 catalyst achieved a steady conversion of 72% in lab-scale tests.
• Pilot plant tests demonstrated a remarkable 20% higher conversion than the gas phase alone.
• The catalyst maintained steady conversion for 65 hours over 4 days in pilot trials.

Conclusions:

• Ruthenium on γ-Al2O3 is an effective catalyst for oxidizing NO to NO2 under Ostwald process conditions.
• This catalytic approach represents a significant step towards intensifying nitric acid production.
• The findings support the industrial application of Ru/γ-Al2O3 for enhanced fertilizer manufacturing.