Systems and methods for direct air capture of carbon dioxide or other gases utilize a calcium sorbent in a manner that allows for wide scale, relatively low cost implementation. In particular, a calcium sorbent may be provided as a substantially thin coating on one or more substrates and utilized for direct air capture of carbon dioxide through chemisorption. The carbonated sorbent may be disposed of for sequestration of the carbon dioxide or regenerated with capture of carbon dioxide released from the carbonated sorbent during the regeneration process.

Provided herein is a chromatography media composed of a porous solid substrate (such as a membrane, metal, or metallic alloy) that is coated with hydroxyapatite (HA). Also provided is a chromatography media comprising a HA-coated substrate and uses thereof. Thus this disclosure provides a chromatography media composed of a porous solid substrate (such as a membrane, metal, or metallic alloy) that is coated with HA. Also provided is a chromatography media comprising a HA-coated substrate and uses thereof. Methods of preparing the HA-coated substrate are also provided.

A process to reduce siloxanes in a waste plastic pyrolysis oil composition is disclosed. The process can include contacting the waste plastic pyrolysis oil composition with a modified silica gel composition under conditions sufficient to produce a purified waste plastic pyrolysis oil composition. The purified waste plastic pyrolysis oil composition can have at least 50% by weight less siloxanes, preferably at least 60% by weight less siloxanes, as compared to the untreated waste plastic pyrolysis oil composition. The siloxanes can include acyclic siloxanes, cyclic siloxanes, or a combination thereof. The modified silica gel composition can include cobalt or iron compositions.

A process for producing spherical activated carbon is complex; therefore, an adsorbent that has an effective adsorption amount larger than or equal to that of spherical activated carbon and that is easily produced is desired. An adsorption heat pump uses, as refrigerant, carbon dioxide and uses, as an adsorbent, a metal-organic framework including a metal ion and an organic ligand. The metal-organic framework is, for example, MOF-200.

The present disclosure generally relates to a microporous aerogel, processes for preparing a microporous aerogel, and applications for the microporous aerogel. The present disclosure also generally relates to an apparatus for capturing carbon dioxide from a gaseous stream or from the atmosphere, the apparatus comprising a microporous aerogel for selectively adsorbing and desorbing the carbon dioxide.

This invention discloses a method of capturing CO2 from air using solid forms of calcium hydroxide, preferably dry Ca(OH).sub.2 to form CaCO.sub.3. The method is characterized by the use of Ca(OH).sub.2 solid forms stacked in an air contactor device so that the air is forced to flow through the air channels created when aligning the holes of the solid forms with the direction of the airflow. The solids are displaced at an average velocity of 0.005 to 0.05 m/hour. The invention also relates to a method of removing CO.sub.2 from the atmosphere and air contactor device configured to carry out the method of capturing CO.sub.2.

Provided are methods of extracting lithium from a lithium containing solution, as well as the resulting compositions. The method includes supplying a lithium containing solution to a lithium capture step, the lithium capture step being operable to capture lithium from the lithium salt containing solution. The method further includes recovering lithium from the lithium capture step to produce a lithium rich stream. In especially preferred methods, the lithium capture step is performed to increase the lithium to sodium ratio above at least 1:1. Optionally, the lithium rich stream can be purified to remove divalent ions and borate ions. The lithium rich stream is then concentrated by supplying the lithium rich stream to a reverse osmosis step to produce a concentrated lithium rich stream.

The present disclosure provides a multi-channel adsorption tower including a tower body, an upper head, a lower head, tray assemblies, partition assemblies, a support plate, ceramic balls and an adsorbent. The interior of the adsorption tower is divided from bottom to top into a feed chamber, a first-stage adsorption chamber, a second-stage adsorption chamber, a third-stage adsorption chamber and a discharge chamber in sequence by the tray assemblies. Each adsorption chamber is equally divided into four material compartments by the partition assemblies. The adsorption chambers are filled with the adsorbent, and unloading ports are provided at the outside of each adsorption chamber. A feed port is provided at the bottom of the lower head, and a discharge port is provided at the top of the upper head. The feed chamber and the discharge chamber contain ceramic balls. The arrangement provides two material paths in the adsorption tower.

The present disclosure provides a desulfurization and sulfur recovery method for sulfur dioxide flue gas, and belongs to the technical field of non-ferrous metal smelting. The method includes the following steps: desulfurizing the sulfur dioxide flue gas by taking slagging flux limestone or quicklime for smelting or converting process as a desulfurizer, and adsorbing SO.sub.2 in the gas to obtain gypsum residue, calcium sulfite, and the desulfurized flue gas, where SO.sub.2 in the sulfur dioxide flue gas before desulfurization is less than 1 vol %; and recycling the gypsum residue and the calcium sulfite to the smelting or converting furnace for slagging, resolving the SO.sub.2 into smelting off-gas, producing sulfuric acid in acid plant.

An object of the present invention is a method for recycling a metal or several metals M selected from among those belonging to the columns 8 to 12 of the periodic table of elements, present at least partially in the form of metal sulphides in a porous material A comprising at least one mineral oxide and having a sulphur content higher than or equal to 2% by weight. Said method comprises the following successive steps: (1) at least one step of heat treatment of the material A in the presence of oxygen, at a temperature comprised within the range from 350 C. to 900 C.; (2) at least one step of washing the material A derived from step (1) by means of an aqueous solvent; (3) at least one step of extracting the metal(s) M by setting the material A derived from step (2) in contact with a solution S containing at least one carboxylic acid; and (4) at least one step of depositing at least one portion of the metal(s) M over a porous material B different from said material A, by setting the solution S derived from step (3) in contact with said material B.