Reducing energy cost of in situ nitrogen fixation in water using an arc-DBD combination

In this study, a sustainable air plasma-based nitrogen fixation into reactive nitrogen species in water (e.g. nitrate and nitrite) is presented, which mimics the lightning-based nitrogen fixation that occurs in nature. We report a hybrid plasma system that combines a dielectric barrier discharge (DBD) reactor (as an efficient ozone source) and an arc plasma reactor (as an efficient NOx source). This hybrid plasma system completely converts gaseous NOx and O-3 into NOx- in water with almost zero emissions (NOx and O-3). Gaseous outlets, in-liquid species, and electrical parameters were investigated. The energy cost for nitrate production via a single-pass reaction was extremely reduced to 8 MJ mol(-1), which enhanced the applicability of the direct one-step nitrogen fixation into NOx- in water for distributed fertilizer production to decrease the dependence on the Haber-Bosh process toward sustainable agricultural development