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.

Disclosed are a heterogeneous zeolite membrane and a method of preparing the same, and more particularly a heterogeneous zeolite membrane that has CHA and DDR zeolite structures by growing seed particles into a crystal structure different from that of the zeolite membrane and can thus separate CO.sub.2/N.sub.2 and CO.sub.2/CH.sub.4 even under wet conditions, a method of preparing the same, and a method of capturing and removing carbon dioxide using the membrane.

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.

Methods and systems for separating liquid components are disclosed. A vessel is provided containing a solids conveyance device. At least a first portion of the vessel acts as an indirect-contact heat exchanger and a second portion of the vessel contains a filter. A process liquid stream, containing a first component and a second component, is passed into the first portion of the vessel. A portion of the second component is frozen and entrained in the first portion of the vessel into the process liquid stream, resulting in a process slurry stream. The process slurry stream is passed into a second portion of the vessel by the solids conveyance device. The process slurry stream is separated into a solid product stream and a primary liquid product stream by passing the primary liquid product stream through the filter and out of the vessel while separately removing the solid product stream out of the vessel.

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 process is proposed for separating carbon dioxide from a feed stream containing carbon dioxide, in which at least part of the feed stream is subjected to temperature swing adsorption to obtain a first and a second successive stream, wherein, in each case relative to the feed stream, the first subsequent stream is depleted in carbon dioxide and the second subsequent stream is enriched in carbon dioxide, and at least part of the second subsequent stream is subjected to membrane separation to obtain a third and a fourth subsequent stream, the third subsequent stream being depleted in carbon dioxide and the fourth subsequent stream being enriched in carbon dioxide, in each case relative to the second subsequent stream. A corresponding arrangement is also an object of the invention.

A pressurized CO.sub.2 rich gas is cooled down to condense at least part of the stream in a heat exchanger. A bulk of the CO.sub.2 is separated by partial condensation and distillation in order to obtain at least one non-condensable gas from a separation vessel. The non-condensable gas is optionally heated up to a temperature lower than −20° C. (membranes performances is greatly enhanced by low temperature operation). The non-condensable gas is introduced into a membrane permeation unit, producing a residue stream and a permeate stream (the permeate stream is enriched in CO.sub.2). The permeate stream is recycled to the process, optionally after compression. The method is auto-refrigerated, i. e. no external refrigerant is used to provide cooling below 0° C.

A biogas upgrading system can include a multiple stage membrane system that is configured to remove oxygen so that the biogas is upgraded to have a higher concentration of methane, a pre-selected oxygen (O.sub.2) concentration (e.g. less than or equal to 0.2 mol %, etc.), and a pre-selected carbon dioxide (CO.sub.2) concentration (e.g. less than or equal to 5 mol %, etc.). The membrane system can be configured to reject O.sub.2 by utilizing a low CO.sub.2/O.sub.2 selectivity that is within a pre-determined range (e.g. less than 5 or less than 4.5). In some embodiments, the upgraded biogas that is output from the system can be entirely made up of methane, carbon dioxide, and oxygen. In other embodiments, the biogas can be almost entirely composed of these components along with a small amount of nitrogen and a trace amount (e.g. less than or equal to 0.2%-0.1%, etc.) of other components.

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.