The present disclosure is directed to a method for making a MER framework type zeolite, a MER framework type zeolite having a stick-like morphology, and processes for the selective separation of carbon dioxide (CO.sub.2) from multi-component feedstreams containing CO.sub.2 using the zeolite.

A helium-containing stream is recovered from a natural gas feed using a membrane followed by multiple distillation steps. Refrigeration is provided by expanding a bottoms liquid with a higher nitrogen content than the feed, achieving a lower temperature in the process. The helium-enriched vapor is then purified and the helium-containing waste stream is recycled to maximize recovery and reduce the number of compressors needed. The helium-depleted natural gas stream can be returned at pressure for utilization or transportation.

Recovering helium from a gaseous stream includes contacting an acid gas removal membrane with a gaseous stream to yield a permeate stream and a residual stream, removing a majority of the acid gas from the residual stream to yield a first acid gas stream and a helium depleted clean gas stream, removing a majority of the acid gas from the permeate stream to yield a second acid gas stream and a helium rich stream, and removing helium from the helium rich stream to yield a helium product stream and a helium depleted stream. A helium removal system for removing helium from a gaseous stream including hydrocarbon gas, acid gas, and helium includes a first processing zone including a first acid gas removal unit, a second processing zone including a second acid gas removal unit, a third processing zone, and a helium purification unit.

In a method for separating a synthesis gas containing carbon monoxide and hydrogen, a synthesis gas flow from a synthesis gas source is compressed in a compressor and separated into at least three gaseous products. If there is insufficient synthesis gas, at least three separation products are recycled in the compressor in order to separate said products.

A gas inerting system employs a carbon dioxide separation unit to remove carbon dioxide and water from an oxygen depleted gas stream generated from a catalytic oxidation unit and subsequently provides a nitrogen rich inerting gas to a fuel tank and/or to a cargo hold. A method of producing an inert gas passes an oxygen depleted gas stream from a catalytic oxidation unit through a carbon dioxide separation unit and provides a nitrogen rich inerting gas for fuel tank inerting and/or cargo hold fire suppression.

An apparatus and method for reclaiming and filtering helium for reuse in analytical instruments. The method includes inputting the output gas stream from a gas chromatograph split vent and subjecting the input gas stream to a mini-particulate filter. The gas stream is also subjected to a molecular sieve filter and a finishing filter to isolate the helium carrier gas. The finishing filter removes trace contaminants that are not caught in the previous filters. The method utilizes a pump and controller to maintain a constant pressure, preferably between 80 and 100 psi, to avoid back-flow contamination and to ensure movement of the gas stream through the filters. Additionally, the use of a relief valve prevents back pressure from entering into the gas chromatograph. The filtered helium gas may be stored for future use or re-introduced directly to the input carrier gas stream of a gas chromatograph.

Sulfur-crosslinked olefins, particularly sulfur-crosslinked heavy hydrocarbon products having one or more sulfur-crosslinked olefin moieties, may undergo pyrolysis to form sulfur-doped porous carbon having high BET surface area values. Pyrolysis to form the sulfur-doped porous carbon may be particularly efficacious in the presence of a hydroxide base. BET surface areas up to 2000 m.sup.2/g or even higher may be obtained. Such sulfur-doped porous carbon may be prepared by combining a heavy hydrocarbon product with sulfur, heating to a first temperature state to form a liquefied reaction mixture containing a sulfur-crosslinked heavy hydrocarbon, homogeneously mixing a hydroxide base with the liquefied reaction mixture, and pyrolyzing the sulfur-crosslinked heavy hydrocarbon to form sulfur-doped porous carbon.

Recovering helium from a gaseous stream includes contacting an acid gas removal membrane with a gaseous stream to yield a permeate stream and a residual stream, removing a majority of the acid gas from the residual stream to yield a first acid gas stream and a helium depleted clean gas stream, removing a majority of the acid gas from the permeate stream to yield a second acid gas stream and a helium rich stream, and removing helium from the helium rich stream to yield a helium product stream and a helium depleted stream. A helium removal system for removing helium from a gaseous stream including hydrocarbon gas, acid gas, and helium includes a first processing zone including a first acid gas removal unit, a second processing zone including a second acid gas removal unit, a third processing zone, and a helium purification unit.

In accordance with the present invention, disclosed herein is a method comprising the steps for producing lower molecular weight hydrocarbons. Also disclosed herein, is a system utilized to produce low molecular weight hydrocarbons.

A carbon dioxide absorbent of an embodiment includes a solid resin compound containing a structural unit expressed by the following formula (1). X in the formula (1) is a halogen element.