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[Display omitted] • The Aluminum borate/Zinc borate (ATH/ZB) composite powder is synthesized successfully by the mechano-chemistry technology. • The minimum inhibition concentrations of ATH, ZB and ATH/ZB for aluminum dust explosion are determined. • ATH/ZB composite powder shows superior inhibition performance in comparison with ATH and ZB. • Inhibition mechanism of ATH/ZB for aluminum dust explosion is revealed in detail. This study proved that Aluminum hydroxide (ATH)/Zinc borate (ZB) composite powder could be adopted as excellent inhibitor for aluminum dust explosion, which was successfully synthesized by mechano-chemistry technology. Under the actions of collision, friction and combination forces, the surface energies of ATH and ZB particles were activated, leading to the close compounding of ATH/ZB. The inhibition effect of ATH/ZB on aluminum dust explosion was studied experimentally. Results showed that flame propagation behaviors and velocities were inhibited accordingly as the concentrations of inhibitors increased. Moreover, the minimum inhibition concentrations of ATH, ZB and ATH/ZB were determined, corresponding to 1000 g/m3, 1000 g/m3 and 600 g/m3, indicating that ATH/ZB had superior inhibition performance compared with ATH or ZB. Characterization tests were used to analyze the explosion residues. The inhibition mechanism of ATH/ZB for aluminum dust explosion primarily included three aspects: physical coating effect, heat absorbing effect and gas dilution effect. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel high-efficiency composite named PA@NH 2 -MCM41 was synthesized via self-assembly. • Nano-Al dust explosion was completely suppressed by only 33.3 wt% PA@NH 2 -MCM41. • A complex film based on Al x (HiPh y) was formed during the explosion suppression process. • The excellent capacity of PA@NH 2 -MCM41 was due to the synergy between gas and condensed phase effects. A novel chemical suppressant (PA@NH 2 -MCM41) was synthesized via self-assembly. NH 2 -MCM-41 was prepared using diatomaceous earth (DE) as the silica source. FTIR spectra showed that phytic acid (PA) was successfully grafted onto synthesized NH 2 -MCM-41 via hydrogen bonding. The highly ordered mesoporous structure of PA@NH 2 -MCM41 was observed from TEM and small angle X-ray diffraction (SAXRD). The effectiveness of PA@NH 2 -MCM41 in the suppression of nano-Al dust explosions was investigated. Experimental results suggested that the addition of PA@NH 2 -MCM41 could effectively reduce the average flame propagation velocity (V avg) and maximum explosion pressure (P max). After the addition of 16.7 wt% PA@NH 2 -MCM41, the V avg of the gas-phase flame was reduced by 75%. With addition of 28.6 wt% PA@NH 2 -MCM41, the P max of nano-Al dust decreased by 65.7%. As the mass fraction of PA@NH 2 -MCM41was increased to 33.3%, nano-Al dust explosion was completely suppressed. The SEM, FTIR and EDS results showed that a complex sealing film was formed on the surface of the explosion products, which occupied the open sites on the Al surface and thereby interrupted the Al evaporation and surface reaction. Subsequently, the suppression mechanism by which phosphorus containing suppressants consume free radicals and the interaction of PA molecules with the aluminum particle surface were revealed in depth. [ABSTRACT FROM AUTHOR]