Study on the highly efficient synergistic inhibition of wheat dust explosions by edible phytic acid-adenine complexes

Wheat dust poses a significant hazard to grain processing safety due to its high explosion sensitivity. To develop an inhibitor combining high-efficiency explosion suppression with environmentally friendly and edible properties, this study innovatively employed an aqueous phase condensation-freeze-drying method to successfully synthesize a phytic acid-adenine complex (PA-A) using naturally edible phytic acid (PA) and adenine as raw materials. Characterization analyses employing laser particle size analyzer, field-emission scanning electron microscopy with energy-dispersive X-ray spectroscopy (FE-SEM/EDS) confirmed the formation of a lamellar microstructure with highly dispersed phosphorus elements. The suppression effect of PA-A on a 300 g/m 3 wheat dust explosion was systematically investigated evaluated in a vertical tube combustion apparatus (1000×80×80 mm). Results demonstrated that increasing inhibitor concentration (0 vol%-12.5 vol%) progressively suppressed flame propagation, evidenced by color transition from bright yellow to dark red, morphological fragmentation, and discontinuity. Quantitative analysis revealed peak flame propagation velocity decreased from 27.6 m/s to 10.9 m/s (a reduction of 60.5%), maximum temperature declined from 993 °C to 367 °C (a reduction of 63.1%), and the maximum explosion pressure attenuated from 48.3 kPa to 20.1 kPa (a reduction of 59%), with a significant delay (>80%) in the time to reach these peak parameters. Comprehensive analysis based on Thermogravimetry-Differential Scanning Calorimetry (TG-DSC), X-ray Photoelectron Spectroscopy (XPS), and Fourier Transform Infrared Spectroscopy (FTIR) elucidated a multi-level synergistic suppression mechanism involving endothermic cooling, gas-phase dilution, surface isolation, and free radical quenching. This study provides a safe, environmentally friendly, and edible new strategy for controlling grain dust explosions.