Effect of ball milling strategy (milling device for scaling-up) on the hydrolysis performance of Mg alloy waste

AL BACHA, S.; PIGHIN, S.A.; URRETAVIZCAYA, G.; ZAKHOUR, M.; NAKHL, M.; CASTRO, F.J.; BOBET, J.-L.

INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2020 vol. 45 p. 20883 - 20893

0360-3199

Ball milling strategy is of prime importance on the hydrolysis performance of Mg alloywaste. The effect of milling device (e.g. Fritsch Pulverisette 6 (P6) and Australian Uni-Ball-II(UB)), milling atmosphere (H2 and Ar), milling time, nature of the additives graphite andAlCl3 and synergetic effect by chronological or simultaneous addition were examined. Anequivalence between both mills was established and it was shown that the process withthe UB is 10 times longer than that with the P6 to acquire a similar material. Mg alloy milledwithout additives in the P6 under Ar for 10 h improves the hydrolysis performance. Using asingle additive, the best hydrolysis performances are obtained with graphite (yield of 95%of total capacity reached in 5 minutes) due to the formation of a protective graphite layer.By incorporating both additives sequentially, the best material, from the hydrogen productionpoint of view, was Mg alloy milled with G for 2 h and then with AlCl3 for 2 extrahours (full hydrolysis in 5 minutes). Mg alloy milled with the P6 were compared to thosemilled with the UB. Mg alloy milled with graphite or with sequential addition of G and AlCl3under Ar generated more than 90% of their total capacity. Our results confirm thatlaboratory-milling strategy can be scaled-up to industrial scale.