Described is a process for treatment of a fluid comprising an oxidizable contaminant selected from one or both of a sulfide and a thiol, the process comprising the step of contacting the fluid with a first complex of ferric iron and a polyphosphate to oxidize the oxidizable contaminant and generate a second complex of ferrous ion and the polyphosphate.

Disclosed is a method for removing hydrogen sulfide from natural gas. The method includes passing a natural gas feed including methane and hydrogen sulfide (H2S) through a membrane at normal operating conditions. The membrane is an asymmetric hollow fiber membrane or an asymmetric film composite membrane including a porous layer and a nonporous skin layer. The asymmetric hollow fiber membrane or the nonporous skin layer of the asymmetric film composite membrane plasticizes during the method by exposure to condensable gases with high critical temperature under the operating conditions. The membrane preferentially removes H2S over methane from the natural gas feed at a H2S/methane selectivity of from 7 to 40 when measured at 35° C. and 45 bar.

A method for treating liquefied hydrocarbons including acid gases to remove said acid gases while minimizing loss of amine species, said method comprising the steps of contacting the liquefied hydrocarbons with an absorbent aqueous solution of a first amine compound, the first amine compound having the structure: ##STR00001##
wherein R.sub.1 is propane-2,3-diol; R.sub.2 is hydrogen, methyl ethyl, 2-hydroxyethyl, or propane-2,3-diol; and R.sub.3 is hydrogen, methyl, ethyl, 2-hydroxyethyl or propane-2,3-diol.

The invention concerns a method for treating a hydrocarbon feed gas stream containing at least CO.sub.2 and H.sub.2S to recover a high quality purified CO.sub.2 gas stream, comprising a. Separating said hydrocarbon feed gas stream into a sweetened hydrocarbon gas stream, and an acid gas stream; b. Introducing said gas stream into a Claus unit, c. Introducing the tail gas into a hydrogenation reactor and then into a quench contactor of the Tail Gas Treatment Unit (TGTU); d. Contacting said tail gas stream with a non-selective amine-based solvent into a non-selective acid gas absorption unit of the TGTU; e. Sending the off gas to an incinerator; f. Contacting said enriched gas stream (vii) with a selective H.sub.2S-absorption solvent into a selective H.sub.2S-absorption unit thereby recovering a highly purified CO.sub.2 gas stream and a H.sub.2S-enriched gas stream, as well as the device for carrying said method.

Methods of reducing acid gas from a stream, comprising contacting the stream with a solvent system comprising a glycerol derivative are described herein. Disclosed herein is a composition comprising a glycerol derivative and an acid gas. A method for sweetening a natural gas stream comprising contacting a solvent system comprising a glycerol derivative with a natural gas stream is described herein.

Disclosed herein are scavenging compounds and compositions useful in applications relating to the production, transportation, storage, and separation of crude oil and natural gas. Also disclosed herein are methods of using the compounds and compositions as scavengers, particularly in applications relating to the production, transportation, storage, and separation of crude oil and natural gas.

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.

Disclosed is method for removing carbonyl sulphide and/or carbon disulphide from a sour gas stream. The method comprises subjecting the gas stream to simultaneous contact with an absorption liquid, such as an aqueous amine solution, and with a catalyst suitable for hydrolyzing carbonyl sulphide and/or carbon disulphide. To this end, the invention also provides a reactor system wherein both an absorption liquid and a catalyst are present. In a preferred embodiment, the catalyst is a heterogeneous catalyst present on or in an absorption column, either coated on the trays of a column with trays, or contained in the packing of a packed column.

The present invention relates to a composition for scavenging hydrogen sulphide and/or mercaptans in hydrocarbon streams, the composition comprising an oxazolidine compound and a synergistic additive.

Ancillary embodiments and modifications to a homogenizer unit (“PPH”), and methods of use directed to purification of biogas or other raw methane streams. The apparatus includes a homogenizer body, one or more stream inlets (for the raw methane), one or more chilled water inlets, a mixing zone where the water stream is commingled with the raw methane stream, and a venturi immediately downstream from the mixing zone such that the commingled streams are pulled into the venturi resulting in homogenization. The PPH components are insulated to maintain the chilled water of the various streams at a cooled, below ambient temperature, increasing dissolution of the contaminant gases into the chilled water, and producing a purified methane stream including little or no H.sub.2S and CO.sub.2.