A method for carbon dioxide recycle stream processing with ethylene glycol dehydrating in an enhanced oil recovery process includes receiving a first carbon dioxide recycle stream from a hydrocarbon formation, adding ethylene glycol to the first carbon dioxide recycle stream to produce an ethylene glycol and carbon dioxide recycle stream, condensing the ethylene glycol and carbon dioxide stream to produce a multiphase stream, separating the multiphase stream into a water and ethylene glycol stream and a second carbon dioxide recycle stream, separating the water and ethylene glycol stream into a water stream and an ethylene glycol stream, and separating the second carbon dioxide recycle steam into a carbon dioxide reinjection stream and a natural gas liquids stream.

A high selectivity and high CO.sub.2 plasticization resistant polymer comprises a plurality of repeating units of formula (I) for gas separation applications. The polymer may be synthesized from a superacid catalyzed poly(hydroalkylation) reaction.

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Membranes made from the polymer and gas separation processes using the membranes made from the polymer are also described.

An aminal compound is injected into a fluid gas stream including at least one acid gas to reduce the amount of acid gas in the fluid gas stream. Having two reactive sites present in the aminal compound enables a much higher efficiency of acid gas capture than a simple alkanolamine, which isn't effective, for example, under dilute circumstances.

A thin film composite gas separation membrane comprising a polyether block amide copolymer coating layer and a nanoporous asymmetric support membrane with nanopores on the skin layer surface of the support membrane and gelatin polymers inside the nanopores on the skin layer surface of the support membrane. A method for making the thin film composite gas separation membrane is provided as well as the use of the membrane for a variety of separations such as separations of hydrogen sulfide and carbon dioxide from natural gas, carbon dioxide removal from flue gas, fuel gas conditioning, hydrogen/methane, polar molecules, and ammonia mixtures with methane, nitrogen or hydrogen and other light gases separations, but also for natural gas liquids recovery and hydrogen sulfide and carbon dioxide removal from natural gas in a single step.

The present invention relates to a biomimetic-hybrid solvent system for simultaneous capture of H.sub.2S and CO.sub.2 from any gaseous composition. The present invention also relates to a process for upgradation of biogas to bio CNG by removing gaseous contaminants, including microbial removal of H.sub.2S, to obtained purified CO.sub.2. The biomimetic-hybrid solvent system contains three components selected from tertiary amine compounds, a functional colloidal fluid, and an enzyme mimic.

Processes, systems, and associated control methodologies are disclosed that control the flow of biogas during the biogas cleanup process to create a more consistent flow of biogas through the digester, while also optimizing the output and efficiency of the overall renewable natural gas facility. In representative embodiments, a biogas buffer storage system may be used during the cleanup process to control the pressure and flow rate of biogas. The biogas buffer storage system may monitor and control the biogas flow rate to either bring down or increase the digester pressure, thereby maintaining a normalized biogas flow rate.

Compositions of and methods for producing a modified polyimide-containing compound with an alkyl or acyl group, one method including selecting and preparing a polyimide-containing compound to undergo a Friedel-Crafts alkylation or acylation reaction; carrying out the Friedel-Crafts alkylation or acylation reaction on the polyimide-containing compound to bond an alkyl group or acyl group to a reactive site on an aromatic compound of the polyimide-containing compound; cleaving the polyimide-containing compound to produce modified monomers comprising the alkyl group or the acyl group; and using the modified monomers in a reaction to produce the modified polyimide-containing compound, wherein the alkyl group or the acyl group is present in the modified polyimide-containing compound.

Disclosed herein are carbon molecular sieves and methods of making the same through the pyrolysis of a polymer precursor in the presence of a reactive gas stream including a hydrogen source.

A method and apparatus for continuously treating acid gases including recovering absorbent chemicals by introducing streams leaving a regenerator and/or leaving an absorber into a static mixing zone wherein supplemental washing water is added to recover absorbent chemicals. Improvements to the prior art methods are provided where one or more absorbent chemical recovery units are included to increase the amount of recovered absorbent chemicals exiting the regenerator and/or exiting the absorber are increased and/or maximized. Absorbent chemical recovery units can include mixing units where liquid is added to the stream of sour gas and absorbent chemical to mix with and absorb the absorbent chemical from the stream.

A process for producing a deacidified fluid stream from a fluid stream comprising methanol and at least one acid gas and an apparatus for carrying out the process. The process comprising a) an absorption step in which the fluid stream is contacted with an absorbent in an absorber to obtain an absorbent laden with methanol and acid gases and an least partly deacidified fluid stream; b) a regeneration step in which at least a portion of the laden absorbent obtained from step a) is regenerated in a regenerator to obtain an at least partly regenerated absorbent and a gaseous stream comprising methanol, water and at least one acid gas; c) a recycling step in which at least a substream of the regenerated absorbent from step b) is recycled into the absorption step a); d) a condensation step in which a condensate comprising methanol and water is condensed out of the gaseous stream from step b); e) a distillation step in which at least a portion of the condensate from step d) is guided into a distillation column to obtain a top stream comprising methanol and a bottom stream comprising water; which comprises recycling at least a portion of the bottom stream from step e) into the regenerator.