An aminated siliceous adsorbent, which is the reaction product of dried acidified rice husk ash having disordered mesopores and an amino silane, wherein amine functional groups are present on an external surface and within the mesopores of the dried acidified rice husk ash, and wherein the aminated siliceous adsorbent has a carbon content of 24 to 30 wt. %, based on a total weight of the aminated siliceous adsorbent. A method of making the aminated siliceous adsorbent and a method of capturing CO.sub.2 from a gas mixture with the aminated siliceous adsorbent.

A method for separating N.sub.2 from a hydrocarbon gas mixture containing N.sub.2 comprising the steps of: i) providing a bed of adsorbent selective for N.sub.2; (ii) passing the hydrocarbon gas mixture through the bed of adsorbent to at least partially remove N.sub.2 from the gas mixture to produce: (a) N.sub.2-loaded adsorbent and (b) N.sub.2-depleted hydrocarbon gas mixture; iii) recovering the N.sub.2-depleted hydrocarbon gas mixture; iv) regenerating the N.sub.2-loaded adsorbent by at least partially removing N.sub.2 from the adsorbent; and v) sequentially repeating steps (ii) and (iii) using regenerated adsorbent from step (iv); wherein the adsorbent comprises a pyrolized sulfonated macroporous ion exchange resin.

A method for separating natural gas liquids (NGLs) from a hydrocarbon gas mixture containing natural gas liquids and methane, comprising the steps of: i) providing a bed of adsorbent selective for NGLs over methane; ii) passing a hydrocarbon gas mixture containing methane and NGL through the bed of adsorbent to at least partially remove NGLs from the gas mixture to produce: (a) NGL-loaded adsorbent and (b) NGL-depleted hydrocarbon gas mixture; iii) recovering the NGL-depleted hydrocarbon gas mixture; iv) regenerating the NGL-loaded adsorbent by at least partially removing NGLs from the adsorbent; and v) sequentially repeating steps (ii) and (iii) using regenerated adsorbent from step (iv).

A computer-implemented method for designing and assessing the performance of a hollow fibre membrane contactor (MBC) in a natural gas sweetening process using a MBC model is described in an embodiment. The MBC model comprises model parameters, model equations and boundary conditions for calculating data associated with the natural gas sweetening process. The natural gas sweetening process comprises removal of acid gas from natural gas using a solvent comprising at least one component. The method comprises: (i) forming a regression model using empirical data; (ii) determining a Henry's constant of CO.sub.2 in the solvent using the regression model; (iii) inputting the determined Henry's constant of CO.sub.2 in the MBC model as one of the model parameters; and (iv) determining CO.sub.2 absorption in the solvent using the MBC model for designing and assessing the performance of the MBC.

A process for separating components of a fluid mixture using membranes comprising a selective layer made from copolymers of perfluorinated dioxolanes. The resulting membranes have superior selectivity performance for fluid pairs of interest while maintaining fast fluid permeance compared to membranes prepared using conventional perfluoropolymers, such as Teflon® AF, Hyfion® AD, and Cytop®.

Provided are a methane-selective composite membrane comprising: a UiO-66 type organic-inorganic composite nanoporous material, a MIL-100 type organic-inorganic composite nanoporous material, or a ZIF-8 type organic-inorganic composite nanoporous material to which a methane-selective functional group is introduced for selectively separating methane from a gas mixture containing methane/nitrogen, a use thereof, and a method of preparing the same.

Perforated graphene sheets can be used in forming separation membranes. Separation membranes of the present disclosure, which can be used in gas separation processes in some embodiments, can include one or more polymer layers and one or more layers of perforated graphene. Methods for separating a gas mixture can include contacting a gas mixture with the separation membranes, and transiting one or more of the gases through the perforated graphene so as to affect separation.

A process for removal of mercury in a gas dehydration system comprising (a) adding a complexing agent to a recirculated glycol solvent as part of the glycol solution feed prior to or at the dehydration liquid contactor and recirculating continuously with the glycol solvent, (b) selectively reacting the complexing agent with mercury in the wet natural gas to remove the mercury from the dry natural gas product, (c) and feeding the rich glycol with the complexing agent to a regenerator and continuously regenerating.

A hydrophobic adsorbent composition and process for removal of mercury from a gas phase fluid near the water and/or hydrocarbon dew point is disclosed herein.

The present invention involves the use of a two-step membrane system for gas separations. In this two-step membrane system, the membrane system comprises high selectivity and high permeance membranes. The two-step membrane system includes a first membrane section, a second membrane section and an ejector configured to increase the pressure of a lower permeate using the energy from a higher permeate gas pressure. The process provides increase in product recovery and product purity of the product gases. It can also save the cost compared to the system using compressors and external energy to drive the separation of gases.