The present invention relates to an aqueous alkanolamine solution demonstrating low volatility comprising 2-di-methylamino-2-hydroxymethyl-1, 3-propanediol useful for removing acid gases from gaseous mixtures. Said aqueous alkanolamine solution may further comprise one or more of an acid or acid-forming compound, another amino compound, an activator, a physical solvent, or one or more other compounds used in gal-liquid treatment practices. Further, the present invention relates to a process for removing acid gases from a gaseous mixture, preferably hydrogen sulfide, comprising the step of contacting the gaseous mixture with said aqueous alkanolamine solution. Examples of the gaseous mixtures include natural gas, synthesis gas, tail gas, and refinery gas.

The present invention relates to methods for improving carbon capture using entrained catalytic-particles within an amine solvent. The particles are functionalized and appended with a CO.sub.2 hydration catalyst to enhance the kinetics of CO.sub.2 hydration and improve overall mass transfer of CO.sub.2 from an acid gas.

A bio-functional air filter medium is provided with a at least one particle filtration layer that retains particles and at least one bio-functional carrier coated with or having embedded therein antimicrobial, anti-viral and anti-allergenic materials. An air filter element having the bio-functional air filter medium is also disclosed. The bio-functional air filter medium is adapted to bind and capture allergens and block metabolism of bacteria, and provide anti-viral activity to effectively inhibit/deactivate viruses, all while filtering air in high flow, low pressure drop residential, HVAC or air purifier applications.

The present invention relates to an aqueous alkanolamine solution demonstrating low volatility comprising 2-di-methylamino-2-hydroxymethyl-1, 3-propanediol useful for removing acid gases from gaseous mixtures. Said aqueous alkanolamine solution may further comprise one or more of an acid or acid-forming compound, another amino compound, an activator, a physical solvent, or one or more other compounds used in gal-liquid treatment practices. Further, the present invention relates to a process for removing acid gases from a gaseous mixture, preferably hydrogen sulfide, comprising the step of contacting the gaseous mixture with said aqueous alkanolamine solution. Examples of the gaseous mixtures include natural gas, synthesis gas, tail gas, and refinery gas.

An acid gas absorbent includes at least one kind of secondary amine compound represented by formula (1): ##STR00001##
where R.sup.1 is a cyclopentyl group or a cyclohexyl group which may be substituted by a substituted or non-substituted alkyl group having 1 to 3 carbon atoms, R.sup.2 and R.sup.3 each indicate an alkylene group having 2 to 4 carbon atoms, and R.sup.2 and R.sup.3 may each be the same or different, and be a straight chain or have a side chain.

Methods of sequestering carbon dioxide (CO.sub.2) are provided. Aspects of the methods include contacting an aqueous capture ammonia with a gaseous source of CO.sub.2 under conditions sufficient to produce an aqueous ammonium carbonate. The aqueous ammonium carbonate is then combined with a cation source under conditions sufficient to produce a solid CO.sub.2 sequestering carbonate and an aqueous ammonium salt. The aqueous capture ammonia is then regenerated from the from the aqueous ammonium salt. Also provided are systems configured for carrying out the methods.

Disclosed herein is a system for purifying air; for the capture of solid residues (soot), and the transformation of CO.sub.x and NO.sub.x (and even methane) present in contaminated air generated by industrial combustion.

The purifying air system comprises an air entrance (c); a first module (A), made up of mechanical filters; a second module (B), downwards from the first module (A), and it corresponds to a series of small reactors with molecular converters (nucleophile chemical agents) to capture and transform carbon oxides (CO.sub.x) and nitrogen oxides (NO.sub.x); and an exit for decontaminated air (D).

A process for selectively removing hydrogen sulphide relative to carbon dioxide from a gaseous mixture containing at least hydrogen sulphide H.sub.2S and carbon dioxide CO.sub.2, includes a step of contacting the gaseous mixture with an absorbent solution including at least one amine, water, and at least one C.sub.2 to C.sub.4 thioalkanol. A use of the absorbent solution for selectively removing hydrogen sulphide relative to carbon dioxide from a gaseous mixture containing at least hydrogen sulphide and carbon dioxide, is disclosed. Disclosed is a use of at least one C.sub.2 to C.sub.4 thioalkanol as an additive in an absorbent solution including at least one amine, and water, for increasing the selectivity of the absorbent solution for the removal of hydrogen sulphide relative to carbon dioxide from a gaseous mixture containing at least hydrogen sulphide and carbon dioxide.

A scrubbing solution is provided having an absorbent for carbon dioxide based on amines, or ethanolamines, or amino acid salts, or potash, or a combination thereof, and an additive activating the absorption rate, wherein the activating additive is a germanium dioxide. A corresponding method for accelerating the absorption of carbon dioxide is also provided, wherein a carbon dioxide-containing gas is contacted with such a scrubbing solution, wherein the carbon dioxide is physically dissolved in the scrubbing solution and is chemically absorbed with the participation of the absorbent, and wherein the germanium dioxide acts catalytically for at least one reaction step of the chemical absorption of the carbon dioxide.

Methods for treating an industrial byproduct, such as spent, granular, activated carbon, dredge spoils, or contaminated soils involve integrated steps to clean, concentrate, separate and/or otherwise collect hazardous and/or desired materials from such industrial byproducts. The cleaned, concentrated, separated, or collected materials may involve sufficient quantities to be useful to subsequent processors, raw materials, additives, and the like. Other treatment methods involve retaining the clean material stream at sufficient temperatures for sufficient time to separate and concentrate desired material for recovery therefrom, such as precious metals and rare earth elements.