Inhibition of hydrogen evolution from Al alloy dust in dynamic wet dust collection environment using citrus leaf extract

Citrus leaf extract achieves 93.03% hydrogen evolution inhibition efficiency. • Significantly reduces hydrogen explosion risk from environmental fluctuations. • Phenol and (R)-3-pyrrolidinol are the active molecules of Citrus leaf extract. • Active molecules adsorb nearly parallel on Al (1,1,1). • O/N lone pairs donate to Al empty orbitals, forming coordination bonds. This study uses Citrus leaf extract (CLE), to validate inhibitor stability by simulating the internal environment of a wet scrubber, providing an intrinsically safe technology for industrial sites. Hydrogen inhibition experiments showed that the optimal CLE concentration for suppressing hydrogen generation was 4 × 10 −2  wt%, with an inhibition efficiency (η) of 93.03%. Under various environmental interferences, CLE at this concentration maintained stable inhibition performance. Characterization experiments indicated that CLE spontaneously adsorbs onto aluminum alloy dust surfaces, forming protective adsorption layers that prevent hydrolysis and hydrogen generation. DFT calculations revealed that the active molecules donated lone-pair electrons from O and N atoms in polar functional groups to the empty orbitals of Al to form coordination bonds, complementing the hydrogen inhibition mechanism. This study demonstrates that CLE, as a green and economical plant-based inhibitor, can ensure safe operation of wet scrubbers in industrial settings. Download: Download high-res image (398KB) Download: Download full-size image