A process for making a modified, mesoporous activated carbon material from waste oil fly ash. The process involves a physicochemical treatment of a raw waste oil fly ash sample, where the sample is initially refluxed in an acid solution, then activated at about 1000 C. and in the presence of carbon dioxide. The activated carbon may be further functionalized with carboxylic and/or amine groups by refluxing the activated carbon in a second acid solution and/or an ammonia solution. The activated carbon, as prepared, has a BET surface area of 30-400 m.sup.2/g, a total pore volume of 0.25-0.50 cm.sup.3/g and an average pore size of 40-100 . A method for removing hydrogen sulfide from natural gas with the modified activated carbon is also provided.

Disclosed is a device for scrubbing carbon dioxide-contaminated gas for use in a fuel cell. The device comprises at least one first opening for allowing gas to enter or exit the device, at least one second opening for allowing gas to exit or enter the device, and at least one sorbent that is capable of removing carbon dioxide from the gas and is arranged in a form of layers which the gas contacts when it flows from the first to the second opening. The device may further comprise one or two gas preparation units for removing solid and/or liquid contaminants from the gas and for adjusting the temperature and/or humidity of the gas.

An apparatus for capture of CO.sub.2 from the atmosphere comprising an anion exchange material formed in a matrix exposed to a flow of the air.

A sorbent composition such as for the removal of a contaminant species from a fluid stream, a method for manufacturing a sorbent composition and a method for the treatment of a flue gas stream to remove heavy metals such as mercury (Hg) therefrom. The sorbent composition includes a porous carbonaceous sorbent such as powdered activated carbon (PAC) and a solid particulate additive that functions as a flow-aid to enhance the pneumatic conveyance properties of the sorbent composition. The solid particulate additive may be a flake-like material, for example a phyllosilicate mineral or graphite.

A filter is includes a housing and at least first and second adsorbent materials within the housing. The second adsorbent material has different characteristic from the first adsorbent material and is in series with the first adsorbent material. When assembled, a labyrinth arrangement is located between a first port in the housing and the first adsorbent material such that gas travels between the first port and the first adsorbent material by passing through the labyrinth arrangement. A filtration system and methods for humidity control of a liquid tank head space uses a filter, including first and second adsorbent and a diffusion channel or labyrinth arrangement.

An assemblage of substantially round particles with a mean diameter between 0.1 and 4 mm, more preferable between 0.3 to 2 mm and most preferable between 0.8 to 1.2 mm, wherein the density of the assemblage determined by ISO 697 is between 250 kg/m3 and 400 kg/m3 is disclosed. The substantially round particles comprise at least one microporous material and optionally at least one binder, wherein the assemblage comprises a pore volume, wherein the pore volume comprises pores resulting from void space between different ones of the substantially round particles and pores within the substantially round particles.

The present invention concerns a device and process for capturing CO.sub.2 from air. The device comprises (a) a membrane at least partly permeable for air comprising a solid state CO.sub.2 sorbent; (b) at least one sorption chamber; (c) at least one regeneration chamber; (d) means for transporting the membrane from the sorption chamber to the regeneration chamber and back; (e) an inlet for receiving air located on one end of the membrane and an outlet for discharging air depleted in CO.sub.2 located on the other end of the membrane in the sorption chamber, wherein the device is configured to allow air to flow from the inlet to the outlet through the membrane; (f) means for flowing stripping gas through the membrane into the regeneration chamber; (g) at least one outlet for discharging CO.sub.2, located in the regeneration chamber; and (h) heating means for heating the regeneration chamber. The device according to the invention provides an efficient and low-cost solution for capturing CO.sub.2 directly from air.

An adsorber for utilization in purification systems for cryogenic fluid processing can include a first layer of adsorbent material and a second layer of adsorbent material within a bed of adsorbent material within the adsorber. The first layer can include alumina or other water removal adsorbent material while the second layer can include NaMSX or other suitable molecular sieve adsorbent material. The first layer can be sized to be substantially smaller than the second layer to facilitate a pre-selected ratio of water adsorption to molecular sieve adsorption so that water can break through the first layer to the second layer during purification operations while the volume of the adsorber can be provided in a much smaller size with much less adsorbent material utilized in the bed as compared to conventional designs. Embodiments can provide an increased purification operational capacity with reduced need for adsorbent material.