Lithium-mediated nitrogen reduction is a proven method to electrochemically synthesize ammonia; yet the process has so far been unstable, and the continuous deposition of lithium limits its practical applicability. One...

Boosting ammonia with a little oxygen Ammonia synthesis from nitrogen for fertilizer production is highly energy intensive. Chemists are therefore exploring electrochemical approaches that could draw power from renewable sources while generating less waste. One promising cycle involves the reduction of lithium ions at an electrode, with the resultant metal in turn reducing nitrogen and regenerating the ions. Li et al . report the counterintuitive result that small quantities of oxygen could enhance the efficiency of this process, which they attribute to diffusional effects that limit excessive lithium reduction. —JSY

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The lithium-mediated ammonia synthesis is so far the only proven electrochemical way to produce ammonia with promising faradaic efficiencies (FEs). However, to make this process commercially competitive, the ammonia formation rates per geometric surface area need to be increased significantly. In this study, we increased the current density by synthesizing high surface area Cu electrodes through hydrogen bubbling templating (HBT) on Ni foam substrates. With these electrodes, we achieved high ammonia formation rates of 46.0 ± 6.8 nmol s −1 cm geo −2 , at a current density of −100 mA/cm geo −2 at 20 bar nitrogen atmosphere and comparable cell potentials to flat foil electrodes. The FE and energy efficiency (EE) under these conditions were 13.3 ± 2.0% and 2.3 ± 0.3%, respectively. Additionally, we found that increasing the electrolyte salt concentration improves the stability of the system, which is attributed to a change of Li deposition and/or solid electrolyte interphase.

Lithium-mediated non-aqueous electrochemical ammonia synthesis (LiMEAS) as an efficient and green ammonia production way was studied by GCMS in different organic electrolytes to evaluate the stability of electrochemical systems.

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The current study attempts to understand the relationships among Environmental Quality (EQ), Human Development (HD) and political and governance regimes in a cross‐country framework through secondary data analysis. The underlying hypothesis is that in addition to income, as reflected from the literature on the Environmental Kuznets Curve hypothesis, several other factors, including socioeconomic (e.g. human development and corruption) and sociopolitical (e.g. ability to exercise democratic rights) factors, may influence environmental policy‐making, and thereby environmental sustainability, in a country. The EQ (i.e. environmental sustainability) of the countries in the current study is denoted by their Environmental Performance Index (2008). Human development is represented by Human Development Index (2007). Democracy Index (2008) and Corruption Perceptions Index (2008) are considered as proxies for political transparency in a country and its susceptibility to rent‐seeking activities, respectively. The cross‐country empirical findings confirm the closer association between the socioeconomic and sociopolitical factors and sustainable development. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment.

Experiments with the continuous precipitation of calcium carbonate are reported in this study. Particle size distributions were measured on-line and interpreted by means of the simultaneous nucleation and the transformation models developed in part 1 of this sequence. Three regimes of precipitation are reported in this study, governed by the supersaturation and liquid phase [Ca2+]/[CO3 2-] ionic ratio. These comprise of a heterogeneous regime involving calcite and vaterite nucleation at moderate [Ca2+]/[CO3 2-] ionic ratio in an unscaled reactor, homogeneous nucleation of vaterite followed by transformation to calcite in a scaled reactor at low and moderate [Ca2+]/[CO3 2-] ratio, and formation of stable vaterite at high [Ca2+]/[CO3 2-] ratio. The particle size distributions in the different regimes are well fitted by the applicable model from part 1 or earlier studies of single-species precipitation. Where appropriate, kinetic parameters obtained from the fits are correlated with supersaturation by power law models.