A process and a plant for purifying a crude gas stream containing sulfur components and hydrocarbons by gas scrubbing using a scrubbing medium which is selective for sulfur components in an absorption column. Heavy hydrocarbons and heavy mercaptans are removed from the crude gas in a lower section of the absorption column and the resulting, loaded scrubbing medium stream is fed separately from the other loaded scrubbing medium streams to a hot regeneration column. A vapor stream enriched in water, hydrocarbons and sulfur components is obtained as overhead product from the hot regeneration column and this stream is cooled to below its dew point and is separated in a gas-liquid-liquid phase separation apparatus. The resulting, organic liquid phase contains heavy hydrocarbons and heavy mercaptans and can thus be discharged from the process or the plant, as a result of which accumulation thereof in the scrubbing medium is prevented.

A method to purify a hydrocarbon gas with hydrogen sulfide as an impurity comprises: (a) charging a chamber with a bed of active-metal carbide of a predetermined mesh-size range; (b) conducting the hydrocarbon gas through the bed of active-metal carbide, forming additional hydrocarbon gas by reaction of the active-metal carbide and the hydrogen sulfide; and (c) filtering from the chamber the hydrocarbon gas without the hydrogen sulfide.

A process is disclosed for the removal of hydrogen sulfide (H.sub.2S) from natural. This process provides for passing a natural gas feedstream comprising H.sub.2S though a regenerable adsorbent media which adsorbs H.sub.2S to provide an H.sub.2S-lean natural gas product and H.sub.2S. The regenerable adsorbent media of the present invention is a tertiary amine functionalized cross-linked macroporous polymeric adsorbent media.

A process for the removal of hydrogen sulfide and sulfur recovery from a H.sub.2S-containing gas stream by catalytic direct oxidation and Claus reaction through two or more serially connected catalytic reactors, wherein a specific control of the oxygen supplement is operated. The control and improvement of the process is obtained by complementing, in each major step of the process, the H.sub.2S-containing gas stream by a suitable flow of oxygen, namely before the H.sub.2S-containing gas stream enters the Claus furnace, in the first reactor of the process and in the last reactor of the process. Especially in application in a SubDewPoint sulfur recovery process the H.sub.2S/SO.sub.2 ratio is kept constant also during switch-over of the reactors R1 and R by adding the last auxiliary oxygen containing gas directly upstream the last reactor R so that the H.sub.2S/SO.sub.2 ratio can follow the signal of the ADA within a few seconds.

The present invention concerns the use, for gas separation, of at least one zeolite adsorbent material comprising at least one FAU zeolite, said adsorbent having an external surface area greater than 20 m.sup.2.Math.g.sup.−1, a non-zeolite phase (PNZ) content such that 0<PNZ≦30%, and an Si/Al atomic ratio of between 1 and 2.5. The invention also concerns a zeolite adsorbent material having an Si/Al ratio such that 1≦Si/Al<2.5, a mesoporous volume of between 0.08 cm.sup.3.Math.g.sup.−1 and 0.25 cm.sup.3.Math.g.sup.−1, a (Vmicro−Vmeso)/Vmicro ratio of between −0.5 and 1.0, non-inclusive, and a non-zeolite phase (PNZ) content such that 0<PNZ≦30%.

Disclosed is an absorbent containing an amine for absorption of an acid gas in a biogas, and a biogas purification system using the same.

A treatment composition for remediating for remediating H.sub.2S, CO.sub.2 and other contaminant(s) in a fluid mixture of contaminated liquids and gasses comprising: a hydrocarbon based liquid; and at least one hydroxide compound dispersed or dissolved into the hydrocarbon based liquid. The at least one hydroxide compound dispersed or dissolved into the hydrocarbon based liquid constitutes 30-50 wt % of the treatment composition, the at least one hydroxide compound includes at least one of potassium hydroxide and sodium hydroxide, and a pH of the treatment composition is in a range of 13-14.0.

There is an absorbent mixture usable for the removal of sour gases from gas mixtures. The mixture has at least one organic base having a pK.sub.b (in water) less than or equal to 3.2; at least one alcoholic solvent of general formula R(OH).sub.n having a boiling temperature above or equal to 100° C. at ambient pressure, wherein R is a linear or branched saturated alkyl group having a number of carbon atoms between 2 and 20 and n is a whole number varying between 1 and 20; an aprotic polar solvent having a dielectric constant ε at 25° C. greater than or equal to 30, a viscosity μ at 25° C. less than or equal to 14 cP, preferably less than or equal to 12 cP; and a boiling temperature at normal pressure equal to or above 130° C. There is also a process for the removal of sour gases using the absorbent mixture.

Disclosed in certain embodiments are methods of removing water from a gas feed stream comprising mercaptans and water during an adsorption step of an adsorption cycle.

A non-aqueous solvent system configured to remove acidic gas from a gas stream comprises a solution formed of a chemical absorption component and a physical absorption component. The chemical absorption component includes a nitrogenous base, wherein the nitrogenous base has a structure such that it reacts with a portion of the acidic gas. The physical absorption component includes an organic diluent that is non-reactive with the acidic gas and that has a structure such that it absorbs a portion of the acidic gas at a pressure above atmospheric pressure. The solvent system has a solubility with water of less than about 10 g of solvent per 100 mL of water.