Synergistic effects of lanthanum ferrite perovskite and hydrogen to promote ammonia production during microalgae catalytic pyrolysis process.

Ammonia (NH) production from nitrogen-enriched renewable resources pyrolysis is a green, clean, and sustainable technology. In this paper, lanthanum ferrite perovskite (LaFeO) and hydrogen (H) atmosphere were combined to enhance NH production during microalgae pyrolysis. The catalytic pyrolysis of microalgae pyrolysis was carried out in a fixed bed reactor. The results show that the synergistic effects between H and LaFeO promote the fuel-nitrogen transfer into gas phase, while nitrogen in biochar and bio-oil significantly decreases. H and LaFeO not only favor the conversion of protein-N to pyridinic-N, pyrrolic-N, and quaternary-N in char, but also accelerate the deamination of amides, pyrroles, and pyridines, thus facilitating the formation of NH. Pyrolysis temperature plays a considerable role in distribution and conversion of N-species. Increasing temperature increases NH and HCN yields, the maximum NH yield reaches 47.40 wt% at 800 °C. Moreover, LaFeO shows considerable stability during 10 cyclic operations.