Systems and methods for preventing formation of carbonyl sulfide in the production of sweet gas using an amine-lean aqueous solution and metal oxide adsorbent material. In embodiments, a method may include producing, via an amine absorption column supplied with a raw gas stream that includes fractions of hydrogen sulfide (H.sub.2S), carbon dioxide (CO.sub.2), and carbon monoxide (CO), (1) a sweet gas stream that includes the fractions of the CO and (2) an amine-rich aqueous solution that includes the H.sub.2S and CO.sub.2. The method may include heating the amine-rich aqueous solution to produce a heated amine-rich aqueous solution. The method may include producing, via an amine regenerator supplied with the heated amine-rich aqueous solution (1) an acid gas stream that includes the H.sub.2S and CO.sub.2 and (2) an amine-lean aqueous solution. The method may include producing, via adsorption in a metal oxide adsorbent vessel, an effluent stream that includes the CO.sub.2.

Steric effects on amine sites beta to amide or ester functional groups are utilized to result in a family of CO.sub.2 solvents with an unprecedented hybridization of chemisorption and physisorption properties. These versatile solvents provide very high CO.sub.2 working capacities in applications typically involved with physical solvents such as Selexol, Genosorb, Fluor Solvent, Purisol, and Rectisol with the added benefit of operation near ambient conditions without the need for solvent chilling along with the potential for high pressure recovery of CO.sub.2. The non-aqueous BAC solvents can also be tailored for low partial pressure CO.sub.2 removal as required in such applications as biogas/landfill gas upgrading and CO.sub.2 removal from industrial processes such as cement and steel manufacturing where they benefit from lower energy requirements for regeneration compared to tradition aqueous amine solution, regeneration under 1 bar CO.sub.2 without steam stripping, reduced corrosion potential, reduced solvent loss, reduced environmental impact, higher volumetric CO.sub.2 uptake compared to standard commercialized processes involving physical solvents, and operation at ambient pressure without the need for feed gas compression.

The use of a composition including at least one acido-basic neutralising agent for decontaminating an atmosphere contaminated by a corrosive gas, the acido-basic neutralising agent having at least 2 pKa's and being characterised by: pKa 1≤pKa 2, pKa 1>2, pKa 2<12, 4<½ (pKa 1+pKa 2)<10 pKa 1, representing the smallest of the basic pKa's and pKa 2 representing the largest of the acidic pKa's. Also, a method for decontaminating an atmosphere contaminated by a corrosive gas comprising the spraying of the neutralising agent, and to a decontamination device.

Embodiments relate to a gas dehydration drying agent solution composition, comprising a solvent that includes at least one glycol having a number average molecular weight from 40 g/mol to 500 g/mol and from 0.01 wt % to 8.00 wt % of a cyclohexylamino sulfonic salt.

An apparatus includes a captured carbon dioxide input. The captured carbon dioxide input is coupled to receive captured carbon dioxide from a direct air capture system. The apparatus uses the captured carbon dioxide as a low global warming refrigerant to provide cooling functionality in automotive, commercial, and industrial applications, or other operations involving low global warming refrigerants. In various embodiments, the apparatus is a refrigeration apparatus or a heat pump apparatus. Low global warming carbon dioxide refrigerant is natural, non-toxic, non-flammable, and abundant when obtained from a direct air capture system. Moreover, carbon dioxide refrigerant has a high heat transfer coefficient and has a global warming potential (GWP) of one. Carbon dioxide refrigerant is a more sustainable and efficient coolant option than common refrigerants, such as R22, R152, R404a, and R1234yf refrigerants.

Intensification techniques are described for enhancing biocatalytic CO.sub.2 absorption operations, and may include the use of a rotating packed bed, a rotating disc reactor, a zig-zag reactor or other reactors that utilize process intensification. Carbonic anhydrase can be deployed in the high intensity reactor free in solution, immobilized with respect to particles that flow with the liquid, and/or immobilized to internals, such as packing, that are fixed within the high intensity reactor.

The invention discloses methods and apparatus(es) for the removal and control of pollutants such as gases and suspended particulates in the air of an enclosed space or an outdoor environment by passing the air through absorbent media. The absorbent media includes any liquid, solid or combination of liquid and solid media that is capable of absorbing a material in which it comes in contact. In one aspect of the invention, formaldehyde is removed by air sparging through a liquid such as water, optionally containing additional scavenging agents.

Disclosed herein are acid gas absorbents that afford high acid gas (CO2) absorption amount per unit volume and high absorption speed and can prevent the absorbent components from diffusing. The acid gas absorbent contains an amine compound of the formula (1) and a cyclic amine compound of the formula (3) or (3′): ##STR00001##

CO.sub.2 capture processes and systems can be improved by recovering thermal energy from particular streams for reuse in the stripping stage. Thermal energy can be recovered from the overhead gas stream of a stripper operated under vacuum pressure conditions, and thermal energy can also be recovered from a flue gas. A heat transfer circuit can be implemented for recovering thermal energy by indirect heat transfer from the overhead gas stream, a flue gas stream, and/or other streams to a heat transfer fluid. The heat transfer circuit can include multiple heat recovery loops arranged in parallel and the heated fluid can be supplied through a reboiler of the stripper to heat the solution in the reboiler.

An embodiment of the present invention relates to an aqueous solvent solution for absorbing carbon dioxide, and a process using an aqueous solvent solution for absorbing carbon dioxide. The aqueous solvent solution having a catalytic compound dissolved in the water that is an alkali salt of an N-substituted amino acid and at least one base that is dissolved in water. The catalytic compound assisting in forming a bicarbonate.