Zinc phytate@chitosan bio-powder renders explosion suppression of titanium powder involved in industrial processes

Titanium powder easily accumulates during industrial processes, and its high reactivity poses unavoidable hazards to both industrial operations and human safety. To suppress the explosion of titanium powder, zinc phytate (Zn-PA) and chitosan (CS) are mixed and prepared into a new bio-inhibitor using hydrothermal-solvothermal synthesis. The suppression effects of Zn-PA@CS bio-powder on the explosion pressure and temperature of titanium powder under different inerting ratios (α) are investigated using a 20 L spherical explosion testing system. The results show that when the α of Zn-PA@CS bio-powder is 0.8, the maximum explosion pressure (P_max) and the maximum rate of pressure rise ((dP/dt)_max) of titanium powder decrease by 82.8% and 91.2%, respectively. Moreover, the maximum flame temperature (T_p) drops from the initial 647 °C–38 °C. Combined with TG-DSC analysis, Zn-PA@CS bio-powder produces phosphorus-containing substances during high-temperature thermal decomposition, which consume a large number of free radicals essential for the explosion. Furthermore, Zn-PA@CS bio-powder generates solid and gaseous substances, leading to the formation of a dense carbonaceous residue that covers the titanium powder, acts as an effective barrier, and dilutes oxygen concentration, thereby further inhibiting the explosion reaction. The Zn-PA@CS bio-powder exhibits a synergistic effect in both physical and chemical suppression. This study provides technical support for developing biomass explosion suppression powder and for preventing and controlling explosion accidents in industrial production.