An apparatus that includes (A) an atmospheric water extraction unit; and (B) a direct air capture unit positioned downstream of and in communication with the atmospheric water extraction unit, wherein the apparatus is capable of reversibly operating in (i) adsorption mode to adsorb water and CO.sub.2 from an incoming air stream and (ii) regeneration mode to release adsorbed water and CO.sub.2, wherein the atmospheric water extraction unit comprises a first desiccant bed comprising a sorbent that adsorbs water from an incoming air stream during adsorption mode and releases water during regeneration mode, and wherein the direct air capture unit comprises a first moisture-responsive CO.sub.2 sorbent bed comprising a sorbent that adsorbs CO.sub.2 from an air stream during adsorption mode and releases CO.sub.2 upon contact with water vapor during regeneration mode.

Some embodiments of the disclosure correspond to, for example, a method for controlling a scrubber containing an adsorbent. The scrubber may be configured to cycle between scrubbing at least one pollutant/gas from a stream of gases with the pollutant/gas being adsorbed onto the adsorbent, and regenerating at least some of the adsorbent and thereby purging at least some of the one pollutant and/or first gas from the adsorbent via a regeneration gas flow. The method may include flowing a stream of gases through the scrubber, the scrubber including the adsorbent and adsorbing at least some of the one pollutant/gas from the stream of gases onto the adsorbent during an adsorption phase over a first time period. The method may also include purging at least a portion of the one pollutant/gas from the adsorbent during a regeneration phase over a second time period with a regeneration gas flow, and cycling therebetween.

A method of purifying gaseous mixtures, for example ternary or quaternary gaseous mixtures, using a sorbent media comprising two or more sorbent materials. The method involves obtaining a target gas from a gaseous composition comprising the target gas, a first gas and a second gas, and optionally further gases by contacting the gaseous composition with the sorbent media to remove at least some of the first gas and at least some of the second gas from the gaseous composition. The sorbent media comprises at least a first sorbent material and a second sorbent material; wherein the first sorbent material has a higher adsorption selectivity for the first gas than for the target gas; and wherein the second sorbent material has a higher adsorption selectivity for the second gas than for target gas. The method may be particularly useful for the separation of pure ethylene, methane or propylene from such gaseous mixtures. A sorbent media and an apparatus for obtaining a target gas from such a gaseous composition are also disclosed.

A system and method of pre-purification of a feed gas stream is provided that is particularly suitable for pre-purification of a feed air stream in cryogenic air separation unit. The disclosed pre-purification systems and methods are configured to remove substantially all of the hydrogen, carbon monoxide, water, and carbon dioxide impurities from a feed air stream and is particularly suitable for use in a high purity or ultra-high purity nitrogen plant. The pre-purification systems and methods preferably employ two or more separate layers of hopcalite catalyst with the successive layers of the hopcalite separated by a zeolite adsorbent layer that removes water and carbon dioxide produced in the hopcalite layers.

The invention relates to the intensification of hydrogen PSA processes through utilization of specifically engineered core-shell composite adsorbents. Different embodiments of core-shell adsorbents can be used with either high or low heat capacity cores, and different adsorbent shells (e.g. activated carbon, zeolite, silica gel, alumina etc.) resulting in higher mass transfer rates and hence sharper mass transfer fronts during the PSA process. The location of the limiting impurity front determines the product purity. Therefore, with sharper impurity fronts, lower height of adsorbent bed is required, and cycle time can be proportionally reduced. Also, thermal swing during the PSA can be reduced by use of such adsorbents. The use of a high heat capacity core to reduce the thermal swing, leads to higher overall working capacity of the adsorbent bed.

A method and apparatus for purifying air via a pre-purification unit (PPU) of an air separation unit (ASU) system can include passing air through a first adsorber of the PPU to purify the air for operation of the ASU system while it is at or below a first pre-selected operational capacity. In response to the operational capacity of the ASU system needing to be increased to a level above the first pre-selected operational capacity threshold, a second adsorber can be brought on-line in parallel with the first adsorber or in series with the first adsorber to provide improved purification capacity to account for the increased demand for purification capacity resulting from the increased operational capacity of the ASU system. This second adsorber can be different from the first adsorber (e.g. different in size, adsorption capacity for impurities within air, and/or configuration, etc.).

A radial adsorber can be configured to facilitate utilization of different layers of material. The radial adsorber, system using at least one radial adsorber, and methods of utilizing embodiments of the radial adsorber can help permit improved efficient operation of fluid purification processing while also being configured to minimize, if not fully avoid, being susceptible to the effect of fluidization.

The present disclosure describes an evaporative emission control canister system that includes: one or more canisters comprising at least one vent-side particulate adsorbent volume comprising a particulate adsorbent having microscopic pores with a diameter of less than about 100 nm; macroscopic pores having a diameter of about 100 - 100,000 nm; and a ratio of a volume of the macroscopic pores to a volume of the microscopic pores that is greater than about 150%, and having a retentivity of about 1.0 g/dL or less. The system may further include a high butane working capacity adsorbent. The disclosure also describes a method for reducing emissions in an evaporative emission control system.

A pressure swing adsorption apparatus for the removal of one or more components such as oxygen from a mixture of gases such as air is disclosed. The apparatus includes pairs of columns (14, 16) for receiving a stream of compressed air with one column operating in a working mode whilst the other said column operates in a purging mode. The columns contain carbon molecular sieve material (26) for adsorbing oxygen and a desiccant material formed into a plurality of tubes (28).

An evaporative emission control canister system comprises an initial adsorbent volume having an effective incremental adsorption capacity at 25° C. of greater than 35 grams n-butane/L between vapor concentration of 5 vol % and 50 vol % n-butane, and at least one subsequent adsorbent volume having an effective incremental adsorption capacity at 25° C. of less than 35 grams n-butane/L between vapor concentration of 5 vol % and 50 vol % n-butane, an effective butane working capacity (BWC) of less than 3 g/dL, and a g-total BWC of between 2 grams and 6 grams. The evaporative emission control canister system has a two-day diurnal breathing loss (DBL) emissions of no more than 20 mg at no more than 210 liters of purge applied after the 40 g/hr butane loading step.