Catalytic nitrate reduction: kinetic investigations

Kinetic studies of reduction of nitrate ions at Sn-modified Pt electrodes using a quartz crystal microbalance

“…de Vooys et al [9] reported that Pd-Cu electrodes showed a very high activity along with a good N 2 selectivity. These observations are in good agreement with the well-known catalytic performance of Pd-Cu catalysts for the reduction of nitrate by hydrogen gas, which has been intensively examined [22][23][24][25][26][27][28] since Vorlop and Tacke [22] first discovered this high catalytic activity. Gootzen et al [7] found that germanium significantly enhanced the electrocatalytic activity of Pd, Pt and Pd-Pt.…”

Reduction of nitrate ions on tin-modified palladium thin film electrodes

“…Until now, Pd-Cu [6], Pd-Ge [7,8], Pt-Ge [7,8], Ni/Pt [9], Co/Pt [9], Cd/Pt [9], Ir/Pt [13], Cd/Au [11] and Pb/Au [12] have been examined. Among them, Pd-Cu binary metal electrodes showed a very high activity with a good N 2 selectivity as reported by Vooys et al, Pd-Cu also showed very high catalytic activity for the reduction of nitrate with hydrogen gas [23][24][25][26][27][28][29]. In our previous communication [30], we reported that Sn-modified Pt and Pd electrodes showed extremely high catalytic activity for the reduction of nitrate ions.…”

State-of-the-art and perspectives of the catalytic and electrocatalytic reduction of aqueous nitrates

“…4) in absence of a reducible support or a promoter metal, which plays an active role in the redox mechanism responsible for nitrate reduction. [6,29,32,33,[39][40][41][42].…”

“…Hörold et al [3,4] reported a mechanism to generate nitrogen [32,33,[39][40][41] The study of the influence of Pd-M ratio on the selectivity of the nitrate reduction pathway has been addressed in different works [18,33]. When catalysts with a low content of the second metal are used, only few bimetallic and large monometallic ensembles are present in the catalyst.…”

“…Hypochlorite ions are responsible for two anodic reactions that influence the process in different ways. First, ammonium ions produced at the cathode because of the nitrate reduction are oxidized and transformed to nitrogen gas by reaction (40) [119,120], improving the selectivity towards nitrogen. On the other hand, nitrite ions are oxidized back to nitrate by reaction (41), decreasing the efficiency of the process.…”