A methane (CH.sub.4) gas is synthesized from carbon dioxide (CO.sub.2) and hydrogen (H.sub.2) using catalyst-dielectric barrier discharge (DBD) plasma at room temperature and atmospheric pressure. In the method and apparatus for synthesizing methane gas of the invention, methane (CH.sub.4) gas, which is synthetic natural gas, can be effectively synthesized only from carbon dioxide (CO.sub.2) and hydrogen (H.sub.2) using DBD plasma at room temperature and atmospheric pressure, and also, additional heating and pressurization devices are not used during the methane gas synthesis process, thus reducing production costs and realizing high-value-added processing due to the absence of risks during the processing.

This disclosure relates to the adsorption and separation of nitrogen in a feed stream (e.g., natural gas) using zeolite ITQ-55 as the adsorbent. A process is disclosed for removing impurities such as nitrogen while producing a high pressure hydrocarbon product. The process involves passing the feed stream through a bed of an adsorbent comprising zeolite ITQ-55 to adsorb nitrogen from the feed stream, thereby producing a product stream depleted in nitrogen at pressure as feed condition without need of recompression. The zeolite ITQ-55 has a mean crystal particle size within the range of from about 0.01 microns to about 40 microns. The feed stream is exposed to the zeolite ITQ-55 at effective conditions for performing a kinetic separation, in which the kinetic separation exhibits greater kinetic selectivity for nitrogen than for methane. The system and method of this disclosure are particularly suitable for use with feed streams utilizing rapid cycle PSA operations.

Systems and methods for controlling an amine contactor are provided. An exemplary method includes determining a pickup ratio for a solvent in the contactor, measuring a temperature of a lower tray of the contactor, adjusting the pickup ratio based, at least in part, on the temperature, and adjusting a flow rate for an injection of lean solvent into the contactor based, at least in part, on the pickup ratio.

A natural gas liquefaction process combined with a synthesis gas production process. At least one part of the heat source required in the synthesis gas production process is provided by at least a portion of the regeneration stream utilized to pretreat the natural gas to be liquefied.

Various illustrative embodiments of a system and process for recovering high-quality biomethane and carbon dioxide product streams from biogas sources and utilizing or sequestering the product streams are provided. The system and process synergistically yield a biomethane product which meets gas pipeline quality specifications and a carbon dioxide product of a quality and form that allows for its transport and sequestration or utilization and reduction in greenhouse gas emissions. The system and process result in improved access to gas pipelines for products, an improvement in the carbon intensity rating of the methane fuel, and improvements in generation of credits related to reductions in emissions of greenhouse gases.

A permanently porous vanadium(II)-containing metal-organic framework (MOF) with vanadium(II) centers and methods for synthesis of such MOF frameworks are provided. Methods for using such compounds to selectively react with N.sup.2 over CH.sub.4 are provided. In the synthetic methods, a vanadium source, such as VY.sub.2(tmeda).sub.2, where Y is a halogen and tmeda is N,N,N′,N′-tetramethylethane-1,2-diamine and a H.sub.2(ligand) are reacted in the presence of acid in a solvent at between 110° C. and 130° C. to form an intermediate product. The intermediate product is collected and washed with a washing agent, such as DMF and acetonitrile, and the vanadium(II) based MOF is activated by heating the washed intermediate product to at least 160° C. under dynamic vacuum.

Various illustrative embodiments of a system and process for recovering high-quality biomethane and carbon dioxide product streams from biogas sources and utilizing or sequestering the product streams are provided. The system and process synergistically yield a biomethane product which meets gas pipeline quality specifications and a carbon dioxide product of a quality and form that allows for its transport and sequestration or utilization and reduction in greenhouse gas emissions. The system and process result in improved access to gas pipelines for products, an improvement in the carbon intensity rating of the methane fuel, and improvements in generation of credits related to reductions in emissions of greenhouse gases.

A system for processing an LNG feed, the system comprising: a bulk removal stage arranged to remove and release CO.sub.2 liquid from the inflow feed, said bulk removal stage including a first HGMT device, and; a polishing stage arranged to receive a lean CO.sub.2 feed from the first HGMT device, said polishing stage arranged to remove and release residual CO.sub.2, the polishing stage including a second HGMT device; wherein the polishing stage is arranged to release an outflow of CO.sub.2 stripped LNG.

The invention relates to a process for recovering methane from digester biogas or landfill gas. More specifically, the invention pertains to a method for producing biomethane that removes impurities from a compressed digester biogas with staged membrane modules of at least two different types, to produce a biomethane having at least 94% CH.sub.4, below 3% of CO.sub.2, and below 4 ppm of H.sub.2S.

Provided is a gas separation device configured to separate a non-hydrocarbon gas from a feed gas containing the non-hydrocarbon gas through use of a gas separation membrane, in which a decrease in operating rate can be suppressed, and economic efficiency is satisfactory. A first membrane module (1) and a second membrane module (2) are arranged in parallel to each other with respect to supply lines for a feed gas. Gas lines for regeneration (14, 15) ((24, 25)), which are branched from a permeate gas line (13) ((23)) of the membrane module (1) ((2)), and which are joined to a feed gas line (21) ((11)) configured to supply the feed gas to the membrane module (2) ((1)), are provided. Under a state in which the feed gas is supplied to the membrane module (1), a permeate gas through the membrane module (1) is supplied, as a gas for regeneration, to the membrane module (2) through the gas lines for regeneration (14, 15). In this case, the membrane module (2) is brought into a non-operation state, and the membrane module (2) is regenerated.