It is an object of the present invention to provide an electrochemical system for producing ammonia from nitrogen oxides which can perform the reaction at room temperature under normal pressure with high ammonia selectivity, and a preparation method thereof.

To achieve the object above, the present invention provides an electrochemical system for producing ammonia from nitrogen oxides characteristically comprising a cathode electrode where the reduction reaction of a complex of nitrogen oxide and a metal complex compound occurs, an anode electrode, a reference electrode, an electrolyte including a metal complex compound, and a nitrogen oxide supply unit.

The present invention also provides a method for producing ammonia from nitrogen oxides, which characteristically comprises the steps of introducing nitrogen oxide in the electrochemical system; forming a complex from the introduced nitrogen oxide and the metal complex compound included in the electrolyte; and performing an electrical reduction reaction of the formed complex. According to the present invention, ammonia can be produced from nitrogen oxides via electrochemical method under normal atmospheric pressure and at room temperature with a high selectivity.

The present application pertains to methods for making metal oxides and/or citric acid. In one embodiment, the application pertains to a process for producing calcium oxide, magnesium oxide, or both from a material comprising calcium and magnesium. The process may include reacting a material comprising calcium carbonate and magnesium carbonate. Separating, concentrating, and calcining may lead to the production of oxides such as calcium oxide or magnesium oxide. In other embodiments the application pertains to methods for producing an alkaline-earth oxide and a carboxylic acid from an alkaline earth cation-carboxylic acid anion salt. Such processes may include, for example, reacting an alkaline-earth cation-carboxylic acid anion salt with aqueous sulfur dioxide to produce aqueous alkaline-earth-bisulfite and aqueous carboxylic acid solution. Other useful steps may include desorbing, separating, and/or calcining.

A system and method of generating ammonia can include an acid and an ammonia precursor.

A slope ?.sup.t1.sub.HC in a linear area of sensor output characteristics for a mixed atmosphere of CO and THC and a slope ?.sup.t1.sub.NH in the linear area of the sensor output characteristics for NH.sub.3 are specified in advance at a time when a time t1 has elapsed since a start of use of an engine. In performing calibration of an NH.sub.3 sensor when a time t2 (greater than the time t1) has elapsed, a slope ?.sup.t2.sub.HC in the linear area of the sensor output characteristics for the mixed atmosphere is specified, a value ?.sup.t2.sub.NH is calculated from an equation ?.sup.t2.sub.NH=?.sup.t2.sub.HC/(?.sup.t1.sub.HC/?.sup.t1.sub.NH), and the calculated value ?.sup.t2.sub.NH is determined as a new slope in the linear area of the sensor output characteristics for an NH.sub.3 gas.

An energy carrier system is provided that produces ammonia with high efficiency and that further produces hydrogen as final product and uses the hydrogen as energy. An energy storage transportation method is further provided that is carried out by using energy carrier system. The energy carrier system includes nitric acid production device, an ammonia production device, and hydrogen production device. The nitric acid production device includes a photo-reactor, a gas supply unit that supplies photo-reactor with gas to be treated containing a nitrogen oxide, water, and oxygen, and light source disposed in the photo-reactor. The light source radiates light including ultraviolet of a wavelength shorter than 175 nm. The energy storage transportation method includes nitric acid production step of producing nitric acid from a nitrogen oxide, ammonia production step of producing ammonia through reduction of nitric acid, and hydrogen production step of producing hydrogen through decomposition of the ammonia.

Reactant materials for use in the synthesis of compounds comprising a non-metal and hydrogen, and methods of making and using the same are provided. The reactant materials generally comprise first and second non-metals, metals, a cation, and a transition metal, and can be formed and used in reactions occurring at relatively low-pressure conditions using heat energy that can be supplied via solar radiation. In particular, the reactant materials can be used in the synthesis of ammonia and various hydrocarbon compounds using air, water, and sunlight.

A reforming device (10) according to the present invention has a compressor (11), a first heat exchanger (12), a desulfurization device (13), a reformer (14), a raw material gas branching line (L11) that extracts a compressed natural gas (21) from a downstream side of the desulfurization device (13) with respect to the flow direction of the natural gas (21) and supplies the natural gas (21) to the reformer (14), and a flue gas discharging line (L12) that discharges a flue gas (22) generated in the reformer (14), wherein the first heat exchanger (12) is provided in the flue gas discharging line (L12), and the flue gas (22) is used as a heating medium of the compressed natural gas (21).

The present disclosure relates to power plants. The teachings thereof may be embodied in processes for producing ammonia and energy, e.g., a method for producing ammonia and energy comprising: spraying or atomizing an electropositive metal; burning the metal with a reaction gas; mixing the reacted mixture with water; separating the mixture into (a) solid and liquid constituents and (b) gaseous constituents; at least partially converting energy of the solid and liquid constituents and of the gaseous constituents; and separating ammonia from the gaseous constituents. Mixing the reacted mixture may include spraying or atomizing the water or the aqueous solution or the suspension of the hydroxide of the electropositive metal into the reacted mixture.

Metal oxide catalyst, preferably in a high surface area form, comprising a metal oxide (e.g. copper, cerium, tin or bismuth) having engineered surface defects in the form of oxygen vacancy defects. The engineered surface defects may be created by plasma treatment for a time sufficient to create oxygen vacancy defects while maintaining morphology and crystallinity of the metal oxide surface. Also a method of producing a metal oxide catalyst for NOx reduction by preparing a high surface metal oxide catalyst and plasma treating the metal oxide particle to induce a controlled level of defects. Also, a method of producing NH.sub.4+ from NOx comprising depositing the metal oxide catalyst onto a substrate to provide an electrode, or a metal coordinated with nitrogen doped carbon, contacting the electrode with an aqueous solution containing NOx species and applying a current to the electrode to reduce NOx species to NH.sub.4+/NH.sub.3.

A novel chemical cycle for producing and capturing ammonia using nitrogen and hydrogen sulfide containing feedstocks is presented. An example of this cycle may start with the reaction between lithium nitride and hydrogen sulfide containing materials to form both lithium sulfide containing material and ammonia, where the produced ammonia is separated and captured. Metallic lithium may then be extracted high temperatures from said lithium sulfide containing material and then may or may not be separated from the said lithium sulfide containing material and other byproducts. The said extracted metallic lithium containing material may then be reacted with nitrogen containing feedstock to form lithium nitride containing material to complete the cycle.