A carbonic acid gas absorbing material on an embodiment includes a liquid carbonic acid gas absorbent and a solid carbonic acid gas absorbent. The liquid carbonic acid gas absorbent is a solution containing a first amine and a solvent. The solid carbonic acid gas absorbent is a second amine of any one among a polyamine, a base material and an amine fixed to the base material, or a polyamine, a base material, and an amine fixed to the base material.

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.

A solution including at least one mixed acetal compound is used to remove hydrogen sulfide and/or mercaptans from a fluid stream, preferably a fluid gas stream. A mixed acetal compound, as provided in the general structure below, includes an N-glycosidic type bond. The mixed acetal includes nitrogen and oxygen as provided below. ##STR00001##

Disclosed are a carbon dioxide absorbent composition in which an N-alkylaminoalkanol; a polyhydroxyamine-based compound; and ethylenediamine and/or diethylenetriamine are mixed, a method for preparing the same, and a method and an apparatus for carbon dioxide absorption/separation using the same. Since the carbon dioxide absorbent according to the present disclosure has superior carbon dioxide absorption capacity and remarkably lower absorbent recycling temperature as compared to the existing absorbents such as monoethanolamine, etc., total energy consumption in the capturing process can be reduced greatly. In addition, since carbon dioxide is recovered at low recycling temperature, contamination by water or absorbent vapor may be prevented.

An aspect of the present invention is a gas treatment method including: an absorption step of bringing a gas to be treated, which contains carbon dioxide and a sulfur compound, into contact with an absorption liquid to be phase-separated by carbon dioxide absorption, to cause the absorption liquid to absorb the carbon dioxide and the sulfur compound; and a first release step of heating the absorption liquid brought into contact with the gas to be treated to a temperature equal to or higher than a temperature at which the carbon dioxide absorbed by the absorption liquid is released from the absorption liquid and lower than a temperature at which the sulfur compound absorbed by the absorption liquid is released from the absorption liquid, to release the carbon dioxide from the absorption liquid.

A process for producing methanol includes the following steps (a) reacting, via a catalytic partial oxidation (CPO) reaction, a CPO reactant mixture (hydrocarbon, oxygen, and optionally steam) in a CPO reactor to produce syngas including H.sub.2, CO, CO.sub.2, H.sub.2O, and unreacted hydrocarbons; and wherein the CPO reactor includes a CPO catalyst; (b) introducing the syngas to a methanol reactor to produce a methanol reactor effluent stream (methanol, water, hydrogen, carbon monoxide, carbon dioxide, and hydrocarbons); and (c) separating the methanol reactor effluent stream into a crude methanol stream, a hydrogen stream, a CO.sub.2 stream, and a purge gas stream. The crude methanol stream comprises includes methanol and water; wherein the purge gas stream includes carbon monoxide and hydrocarbons; and the CO2 stream includes at least a portion of the CO2 of the methanol reactor effluent stream; and (d) recycling at least a portion of the CO2 stream to the CPO reactor.

A transformational energy efficient technology using ionic liquid (IL) to couple with monoethanolamine (MEA) for catalytic CO.sub.2 capture is disclosed. [EMmim.sup.+][NTF.sub.2.sup.−] based catalysts are rationally synthesized and used for CO.sub.2 capture with MEA. A catalytic CO.sub.2 capture mechanism is disclosed according to experimental and computational studies on the [EMmim.sup.+][NTF.sub.2.sup.−] for the reversible CO.sub.2 sorption and desorption.

A method for regenerating an amine-based, acid gas absorbent using a mixed catalyst containing silver oxide and silver carbonate includes the steps of absorbing an acid gas into an acid gas absorbent having an amine group to obtain an acid gas-absorbed absorbent; and regenerating the amine-based, acid gas absorbent by adding a catalyst mixture containing silver oxide and silver carbonate to the acid gas-absorbed absorbent and by removing the acid gas at a temperature ranging from 40° C. to 86° C. When the amine-based acid gas absorbent is an acid gas absorbent solution and when the acid gas that is absorbed into the acid gas absorbent solution is carbon dioxide, the catalyst mixture efficiently promotes decomposition of carbon dioxide-bound carbamate in the acid gas absorbent solution that absorbs the carbon dioxide through a novel catalytic reaction pathway.

A system for high-value utilization of organic solid waste includes an anaerobic digestion unit, a biogas measurement and collection unit and a methane purification and liquefaction unit. The anaerobic digestion unit includes an organic solid waste pretreatment system and an anaerobic digestion device. The biogas measurement and collection unit includes a gas flow meter and a high-pressure biogas collection device. The methane purification and liquefaction unit includes a high-pressure separation tank, a liquefaction pretreatment system, a heavy hydrocarbon and benzene removal device, a two-stage rectification system, a low-temperature pressure liquid storage tank device and a buffer storage tank. The organic solid waste undergoes an anaerobic digestion treatment to produce methane followed by collection, purification and liquefaction.

An absorbent for selective removal of hydrogen sulfide over carbon dioxide from a fluid stream comprises an aqueous solution of a) a tertiary amine, b) a sterically hindered secondary amine of the general formula (I) ##STR00001##
in which R.sub.1 and R.sub.2 are each independently selected from C.sub.1-4-alkyl and C.sub.1-4-hydroxyalkyl; R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each independently selected from hydrogen, C.sub.1-4-alkyl and C.sub.1-4-hydroxyalkyl, with the proviso that at least one R.sub.4 and/or R.sub.5 radical on the carbon atom bonded directly to the nitrogen atom is C.sub.1-4-alkyl or C.sub.1-4-hydroxyalkyl when R.sub.3 is hydrogen; x and y are integers from 2 to 4 and z is an integer from 1 to 4; where the molar ratio of b) to a) is in the range from 0.05 to 1.0, and c) an acid in an amount, calculated as neutralization equivalent relative to the protonatable nitrogen atoms in a) and b), of 0.05 to 15.0%. One preferred amine of the formula I is 2-(2-tert-butylaminoethoxy)ethanol. The absorbent allows a defined H.sub.2S selectivity to be set at pressures of the kind typical in natural gas processing.