Various embodiments may include systems, methods, and devices in which acid produced by a reactor, such as an electrochemical reactor or other type acid producing reactor, is used to produce carbon dioxide (CO.sub.2) from a carbonate and the produced CO.sub.2 is used, or made available for use, for one or more purposes. In some embodiments, the electrochemical reactor may be powered by a renewable energy source.

Various embodiments may include systems, methods, and devices in which acid produced by a reactor, such as an electrochemical reactor or other type acid producing reactor, is used to produce carbon dioxide (CO.sub.2) from a carbonate and the produced CO.sub.2 is used, or made available for use, for one or more purposes. In some embodiments, the electrochemical reactor may be powered by a renewable energy source.

Embodiments of nitric oxide (NO) generation apparatuses, systems, and methods are provided. In some embodiments, an NO generation apparatus may include a reaction chamber having a liquid region and a gas region. The liquid region may be configured to contain a reaction medium and the gas region may be configured to contain a product gas comprising NO. The NO generation apparatus may also include a plurality of electrodes disposed in the reaction medium, and may include an energy source electrically connected to the plurality of electrodes and configured to apply a predetermined voltage or a predetermined current to at least one of the plurality of electrodes to generate NO. The NO generation apparatus may also include an inlet circuit configured to receive a carrier gas, and may include at least one sparger in fluid communication with the inlet circuit and configured to emanate bubbles of the carrier gas in the reaction medium.

Embodiments of nitric oxide (NO) generation apparatuses, systems, and methods are provided. In some embodiments, an NO generation apparatus may include a reaction chamber having a liquid region and a gas region. The liquid region may be configured to contain a reaction medium and the gas region may be configured to contain a product gas comprising NO. The NO generation apparatus may also include a plurality of electrodes disposed in the reaction medium, and may include an energy source electrically connected to the plurality of electrodes and configured to apply a predetermined voltage or a predetermined current to at least one of the plurality of electrodes to generate NO. The NO generation apparatus may also include an inlet circuit configured to receive a carrier gas, and may include at least one sparger in fluid communication with the inlet circuit and configured to emanate bubbles of the carrier gas in the reaction medium.

Electrolytic gas generator and multi-functional current collector for use in same. In one embodiment, the current collector is constructed both to conduct current from an electrode to a conductive lead and to conduct gas generated at the electrode to external tubing. Accordingly, the current collector may be formed by bonding together a top metal plate and a bottom metal plate of similar profiles, each of which may be shaped to include a main portion and a lateral extension. The bottom metal plate may have central through hole in the main portion for receiving gas from the anode. The top metal plate may have a recess on its bottom surface. The recess may have a first end aligned with the through hole on the bottom metal plate and may have a second end at the end of the lateral extension. A lead and tubing may be attached to the lateral extension.

Methods and systems for producing are disclosed. A method for producing iron, for example, comprises: providing an iron-containing ore to a dissolution subsystem comprising a first electrochemical cell; wherein the first anolyte has a different composition than the first catholyte; dissolving at least a portion of the iron-containing ore using an acid to form an acidic iron-salt solution having dissolved first Fe.sup.3+ ions; providing at least a portion of the acidic iron-salt solution to the first cathodic chamber; first electrochemically reducing said first Fe.sup.3+ ions in the first catholyte to form Fe.sup.2+ ions; transferring the formed Fe.sup.2+ ions from the dissolution subsystem to an iron-plating subsystem having a second electrochemical cell; second electrochemically reducing a first portion of the transferred formed Fe.sup.2+ ions to Fe metal at a second cathode of the second electrochemical cell; and removing the Fe metal.

Methods and systems for dissolving an iron-containing ore are disclosed. For example, a method of processing and dissolving an iron-containing ore comprises: thermally reducing one or more non-magnetite iron oxide materials in the iron-containing ore to form magnetite in the presence of a reductant, thereby forming thermally-reduced ore; and dissolving at least a portion of the thermally-reduced ore using an acid to form an acidic iron-salt solution; wherein the acidic iron-salt solution comprises protons electrochemically generated in an electrochemical cell.

Methods and catalysts for oxidizing ammonia to nitrogen are described. Specifically, diruthenium complexes that spontaneously catalyze this reaction are disclosed. Accordingly, the disclosed methods and catalysts can be used in various electrochemical cell-based energy storage and energy production applications that could form the basis for a potential nitrogen economy.

Methods and catalysts for oxidizing ammonia to nitrogen are described. Specifically, diruthenium complexes that spontaneously catalyze this reaction are disclosed. Accordingly, the disclosed methods and catalysts can be used in various electrochemical cell-based energy storage and energy production applications that could form the basis for a potential nitrogen economy.

Methods and systems for producing are disclosed. A method for producing iron, for example, comprises: providing an iron-containing ore to a dissolution subsystem comprising a first electrochemical cell; wherein the first anolyte has a different composition than the first catholyte; dissolving at least a portion of the iron-containing ore using an acid to form an acidic iron-salt solution having dissolved first Fe.sup.3+ ions; providing at least a portion of the acidic iron-salt solution to the first cathodic chamber; first electrochemically reducing said first Fe.sup.3+ ions in the first catholyte to form Fe.sup.2+ ions; transferring the formed Fe.sup.2+ ions from the dissolution subsystem to an iron-plating subsystem having a second electrochemical cell; second electrochemically reducing a first portion of the transferred formed Fe.sup.2+ ions to Fe metal at a second cathode of the second electrochemical cell; and removing the Fe metal.