Prevention of a hydrogen explosion accident in the wet aluminum waste dust collection process based on L-malic acid

Abstract To essentially solve the hydrogen explosion risk in wet aluminum waste dust collection systems employed in aluminum product processing, nontoxic and environmentally friendly L-malic acid was used to inhibit the hydrogen production reaction between aluminum waste dust and water. Experiments and chemical kinetic model analysis showed that when the L-malic acid concentration reached 0.15 g L−1, the hydrogen production reaction was almost completely suppressed. Scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy and adsorption theory were used to analyze the hydrogen suppression mechanism. The results showed that L-malic acid forms a chemical adsorption film on the surface of aluminum waste dust particles that can prevent particles from contacting water and realizes hydrogen suppression by preventing the reaction from proceeding. This method provides a design safety measure to prevent hydrogen explosion in wet aluminum waste dust collection systems and has good application prospects.