Molecular Sieve Compositing Strategy Enabling Tandem Ammoxidation-Oxidation to 2-Nitropropane: Catalyst Design and Industrial-Scale Separation

Conventional nitration methods using concentrated nitric acid pose significant safety and environmental risks. To address this, a dual-base-modified composite catalyst (TS-1@Ti-MWW-OH) was designed for efficient 2-nitropropane synthesis via acetone ammoxidation/oxidation. Structural characterization confirmed that compositing TS-1 with Ti-MWW and modifying with 4-methoxypyridine/ethanolamine increased specific surface area (32%), pore volume (28%), and pore size (1.8 nm), enhancing mass transfer and active site accessibility. Mechanistic studies revealed a synergistic relay catalysis: Ti ⁴⁺ sites on Ti-MWW catalyzed acetone→acetone oxime conversion, while Ti ⁴⁺ on TS-1 oxidized oxime→2-nitropropane, achieving 92.2% yield. Process simulation via Aspen Plus V14 demonstrated industrial-scale production of 13,000 t/year 2-nitropropane (≥ 99.99 wt%) and 760 t/year acetone oxime (≥ 99.8 wt%), with stable operation ≥ 8,000 h/year validated by RADFRAC and tray hydraulics analysis. Additionally, column sizing (height and diameter) and tray hydraulics analysis performed using the Tray Sizing module confirmed that the maximum flooding ratio remains within permissible operating limits.This work provides a sustainable strategy for nitroalkane production through tailored catalyst design and optimized process engineering.