Proposed are a photocatalyst, including titanium dioxide particles including titanium dioxide (TiO.sub.2), a carbon material located on all or part of the surface of the titanium dioxide particles and including at least one selected from the group consisting of graphene, reduced graphene oxide (rGO), and carbon nanotubes (CNTs), and bimetallic nanoparticles supported on the carbon material and including first metal nanoparticles and second metal nanoparticles, and a water treatment method using the same. In the photocatalyst and the water treatment method using the same, the photocatalyst including bimetallic nanoparticles and graphene oxide is prepared, thereby exhibiting high reduction efficiency and high selectivity to nitrogen gas even without the use of an external electron donor.

Proposed are a photocatalyst, including titanium dioxide particles including titanium dioxide (TiO.sub.2), a carbon material located on all or part of the surface of the titanium dioxide particles and including at least one selected from the group consisting of graphene, reduced graphene oxide (rGO), and carbon nanotubes (CNTs), and bimetallic nanoparticles supported on the carbon material and including first metal nanoparticles and second metal nanoparticles, and a water treatment method using the same. In the photocatalyst and the water treatment method using the same, the photocatalyst including bimetallic nanoparticles and graphene oxide is prepared, thereby exhibiting high reduction efficiency and high selectivity to nitrogen gas even without the use of an external electron donor.

A system for adjusting pressure in a reservoir includes a pump system for pumping a fluid into the reservoir and a system for supplying the fluid to the pump system. The fluid supply system includes a conversion device arranged to receive a fuel and a gas mixture comprising at least one oxidant, to react the fuel with the gas mixture and to supply fluid obtained upon reaction, the fluid supply system being arranged to supply at least a portion of that fluid. The fluid supply system further includes a source of the fuel. The fuel comprises hydrogen. The conversion device is arranged to react the fuel with a gas mixture comprising predominantly nitrogen.

A process comprising: subjecting a process gas containing NOx to a stage for absorption of NOx in a suitable absorption means, obtaining nitric acid and a tail gas containing nitrogen, argon and residual NOx; subjecting said tail gas to a treatment which comprises at least one NOx removal stage, obtaining a conditioned tail gas; subjecting at least a portion of said conditioned tail gas to a separation treatment, obtaining a product stream containing argon and a product stream containing nitrogen.

The present disclosure is directed to renewable pathways to nitrogen production and ammonia (NH.sub.3) synthesis that utilize renewable heat as process heat instead of fossil fuels and operates at low to medium pressures (from 0.2-3 MPa). The renewable pathways result in both a decrease or elimination of greenhouse gas emissions as well as avoid the cost, complexity and safety issues inherent in high-pressure processes. Renewable thermochemical looping technology is used that produces nitrogen from air for the subsequent production of ammonia via an advanced two-stage process.

A particle filter for treating exhaust gases includes an SCR catalyst that, when in the presence of a reductant such as ammonia, promotes selective catalytic reduction of NO.sub.x; an active oxidation catalyst that promotes oxidation of hydrocarbons and carbon monoxide; and an oxygen storage catalyst that alternately stores and releases oxygen, enhances soot oxidation, and stores NOx at temperatures below optimal SCR functioning. The particle filter may be included in a system having an oxidation catalytic device (OCD) upstream of the particle filter, and optionally includes one or more SCR converters upstream and/or downstream of the particle filter, and/or an ammonia slip catalyst downstream of the particle filter. The system may further be adapted for operation under a high frequency injection fuel control with an OCD having substantial NOx storage material content, or an NSC for improving the efficiency tradeoffs between soot oxidation during filter regeneration and NO.sub.x reduction.

Bimetallic oxidation catalyst devices include a support body, one or more metal A bulk deposits disposed on the support body, and a plurality of metal B atomic clusters disposed on the surface of each of the metal A bulk deposits. Metal A and metal B are different metals each selected from the group consisting of platinum group metals (PGM), Ag, Au, Ni, Co, and Cu, and substantially no metal B is deposited on the support body. At least 85% by weight of the metal B atomic clusters comprise up to 10 atoms and the maximum metal B atomic cluster size is 200 metal B atoms. The combined loading of metal A and metal B can be less than 1.5% by weight relative to the weight of the support body. Metal A can include Pd, Rh, Rh, or Pd, and metal B can include Pt, Pt, Ag, or Ag.

A process comprising: subjecting a process gas containing NOx to a stage for absorption of NOx in a suitable absorption means, obtaining nitric acid and a tail gas containing nitrogen, argon and residual NOx; subjecting said tail gas to a treatment which comprises at least one NOx removal stage, obtaining a conditioned tail gas; subjecting at least a portion of said conditioned tail gas to a separation treatment, obtaining a product stream containing argon and a product stream containing nitrogen.

One-step solution combustion synthesis (SCS) methods for fabricating durable crystalline transuranic-doped rare earth zirconium pyrochlores are described. Methods are fast, amenable to upscaling, and present a simple strategy for producing crystalline ceramic materials that meet the minimum attractiveness criteria for special nuclear material. The methods include analysis of reactants and reaction conditions to select proper fuel as well as proper fuel content so as to encourage formation of the crystalline product in a single-step synthesis procedure.

For the purification of waste gas containing carbon compounds and nitrogen oxides by means of a regenerative post-combustion system, at least two regenerators (A, B, C) filled with heat accumulator bodies (7a, 7b, 7c) and connected by a combustion chamber (10) are provided, wherein the waste gas is alternately heated in a regenerator (A, B, C), the carbon compounds are oxidised in the combustion chamber (10), and, with the addition of a nitrogen-hydrogen compound, the nitrogen oxides are reduced in the combustion chamber (10) thermally and thus not catalytically. Remaining nitrogen oxides are removed by means of a catalytically active heat accumulator layer (6a, 6b, 6c) and the addition of a further nitrogen-hydrogen compound in the regenerator (A, B, C) from which the clean gas exits.