Provided here are methods and systems to recover greater than 99.9% of sulfur from natural gas and from other processed gases containing hydrogen sulfide derived from refining crude oil and other industrial processes. The method and system involves a sub-dew point reactor unit with separation units for water removal.

The present invention relates to a calcined medium, in particular a catalyst or a catalyst medium or an adsorbent/absorbent mass, in particular in the form of extrudates, pellets, granules or beads, the medium comprising a porous matrix comprising carbonates, clays, zeolites, oxides, or metal and/or silicon hydroxides, and the matrix incorporating hollow mineral microspheres having a different composition in a content of between 0.3 and 50% by weight, in particular between 0.5 and 15% by weight, of the matrix.

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.

A method for cleaning an off-gas from viscose production, essentially containing H.sub.2S and CS.sub.2, comprises passing the gas through a catalytic reactor containing a direct oxidation type catalyst, such as V.sub.2O.sub.5 on silica, to convert H.sub.2S in the gas to elemental sulfur, SO.sub.2 or mixtures thereof, either via the oxygen present in the gas or via oxygen added to the gas stream. Elemental sulfur and SO.sub.2 are removed from the effluent gas from the catalytic reactor, and the unconverted CS.sub.2 is recycled to the viscose production process.

Presented is a catalyst composition having exceptional properties for converting sulfur, sulfur compounds, and carbon monoxide contained in gas streams by catalyzed hydrolysis, hydrogenation and water-gas shift reactions. The catalyst comprises underbedded molybdenum and cobalt with an overlayer of molybdenum and cobalt. These metals are present in the catalyst within certain concentration ranges and relative weight ratios. The underbedded metals are present in the catalyst within a specified range relative to the overlayer and total metals. The underbedded metals are formed by co-mulling an inorganic oxide with the catalytically active metals of molybdenum and cobalt. The co-mulled mixture is calcined and then impregnated with overlaid molybdenum and cobalt.

A system and method including a sulfur recovery system (SRU) having a Claus system, reacting hydrogen sulfide and oxygen in a furnace to give sulfur dioxide, performing a Claus reaction in the furnace to give elemental sulfur, performing the Claus reaction in a Claus reactor to give elemental sulfur at a temperature greater than a dew point of the elemental sulfur, performing the Claus reaction in a Claus cycling reactor to give elemental sulfur at a temperature less than a solidification temperature of the elemental sulfur, depositing the elemental sulfur as solid elemental sulfur on catalyst in the Claus cycling reactor, and regenerating (heating) the Claus cycling reactor thereby forming elemental sulfur vapor from the solid elemental sulfur.

A system and method including a sulfur recovery system (SRU) having a Claus system, reacting hydrogen sulfide and oxygen in a furnace to give sulfur dioxide, performing a Claus reaction in the furnace to give elemental sulfur, performing the Claus reaction in a Claus reactor to give elemental sulfur at a temperature greater than a dew point of the elemental sulfur, performing the Claus reaction in a Claus cycling reactor to give elemental sulfur at a temperature less than a solidification temperature of the elemental sulfur, depositing the elemental sulfur as solid elemental sulfur on catalyst in the Claus cycling reactor, and regenerating (heating) the Claus cycling reactor thereby forming elemental sulfur vapor from the solid elemental sulfur.

A method for preparing a sol comprising TiO.sub.2 and ZrO.sub.2 and/or hydrated forms of TiO.sub.2 and ZrO.sub.2. The method includes mixing a material which includes metatitanic acid in an aqueous phase with a zirconyl compound or with a mixture of several zirconyl compounds. The material is provided either as a suspension or as a filter cake from the sulfate method. The material includes a H.sub.2SO.sub.4 content of 3 to 15 wt.-% relative to a quantity of TiO.sub.2 in the material. The zirconyl compound or the mixture of several zirconyl compounds is mixed in a quantity that is sufficient to provide the sol depending on the H.sub.2SO.sub.4 content.

The present application relates to a process for treating the off gas from a carbon black process, said process comprising the steps of: providing an off gas from a carbon black process, reacting said off gas in a first reaction step forming water and S, and condensing the S at a temperature Tcon where S is in a liquid phase and the water is in gas form thereby achieving a gaseous stream comprising water and a liquid stream comprising S, and wherein the first reaction step is carried out over a monolith catalyst.

A method for preparing a sol comprising TiO.sub.2 and ZrO.sub.2 and/or hydrated forms of TiO.sub.2 and ZrO.sub.2. The method includes mixing a material which includes metatitanic acid in an aqueous phase with a zirconyl compound or with a mixture of several zirconyl compounds. The material is provided either as a suspension or as a filter cake from the sulfate method. The material includes a H.sub.2SO.sub.4 content of 3 to 15 wt.-% relative to a quantity of TiO.sub.2 in the material. The zirconyl compound or the mixture of several zirconyl compounds is mixed in a quantity that is sufficient to provide the sol depending on the H.sub.2SO.sub.4 content.