Elemental sulfur carrying capacity of a hydrocarbonaceous solvent is improved by first loading the solvent with sulfur and subsequent hydrotreatment under conditions that convert at least some of the elemental sulfur in the sulfur loaded solvent to hydrogen sulfide while preserving at least 95% of the monoaromatic and polyaromatic components in the solvent.

An elemental sulfur recovery unit comprising a thermal unit configured to combust an acid gas feed comprising hydrogen sulfide, an oxygen source, and a fuel gas to create a reaction furnace outlet stream, comprising elemental sulfur, a waste heat boiler configured to capture heat from the reaction furnace outlet stream to create a waste heat boiler effluent, a condenser configured to condense the waste heat boiler effluent to produce a non-condensed gases stream and a condensed stream comprising elemental sulfur, a process gas reheater configured to generate a hot gases stream, a hydrogenation reactor configured to convert the hot gases stream to create a hydrogenation effluent comprising hydrogen sulfide, a process desuperheater configured to cool the hydrogenation effluent to generate a cooled effluent, and an absorber unit configured to absorb the hydrogen sulfide from the cooled effluent to produce a hydrogen sulfide recycle stream and a waste gas stream.

Methods for producing cyclododecasulfur are disclosed, that include the steps of: oxidizing a bromide in aqueous solution to produce a mixture of molecular bromine, tribromide, and bromide; reducing water to produce hydrogen and a hydroxide; and reacting a metallasulfur derivative with the molecular bromine, to produce cyclododecasulfur and a metallabromide derivative.

Improved methods of synthesizing ammonia from hydrogen sulfide and lithium nitrate are disclosed. Specifically, in a continuous cycle, hydrogen sulfide reactant is regenerated from the elemental sulfur that is extracted from a product of the ammonia synthesis, and the regenerated hydrogen sulfide is fed back into the ammonia synthesis reaction. The cycle that regenerates the hydrogen sulfide uses either a water-containing or a water and carbon-containing feedstock to facilitate the regeneration of the hydrogen sulfide from the elemental sulfur.

An object of the present invention is to provide a hydrogen sulfide production method enabling efficient recovery of sulfur. The production method is a method for producing hydrogen sulfide from sulfur and hydrogen comprising (1) a reaction step of reacting sulfur and hydrogen to obtain a crude hydrogen sulfide gas, (2) a purification step of purifying the crude hydrogen sulfide gas by bringing the crude hydrogen sulfide gas into contact with aliphatic lower alcohol in a packed tower to precipitate sulfur contained in the crude hydrogen sulfide gas, (3) a discharge step of discharging from inside the packed tower a suspension of sulfur in aliphatic lower alcohol obtained in the purification step, and (4) a filtration step of filtering the aliphatic lower alcohol suspension of sulfur with a filter to obtain a sulfur cake, and the filter 20 is a rotary filter 22 or a leaf filter.

An object of the present invention is to provide a hydrogen sulfide production method enabling efficient recovery of sulfur. The production method is a method for producing hydrogen sulfide from sulfur and hydrogen comprising (1) a reaction step of reacting sulfur and hydrogen to obtain a crude hydrogen sulfide gas, (2) a purification step of purifying the crude hydrogen sulfide gas by bringing the crude hydrogen sulfide gas into contact with aliphatic lower alcohol in a packed tower to precipitate sulfur contained in the crude hydrogen sulfide gas, (3) a discharge step of discharging from inside the packed tower a suspension of sulfur in aliphatic lower alcohol obtained in the purification step, and (4) a filtration step of filtering the aliphatic lower alcohol suspension of sulfur with a filter to obtain a sulfur cake, and the filter 20 is a rotary filter 22 or a leaf filter.

Disclosed are processes for purifying feed streams containing hydrogen sulfide and sulfur-containing impurities by removing sulfur-containing impurities, such as elemental sulfur and polysulfanes, using solid catalytic sorbents. Also disclosed are processes for producing hydrogen sulfide.

An elemental sulfur recovery unit comprising a thermal unit configured to combust an acid gas feed comprising hydrogen sulfide, an oxygen source, and a fuel gas to create a reaction furnace outlet stream, comprising elemental sulfur, a waste heat boiler configured to capture heat from the reaction furnace outlet stream to create a waste heat boiler effluent, a condenser configured to condense the waste heat boiler effluent to produce a non-condensed gases stream and a condensed stream comprising elemental sulfur, a process gas reheater configured to generate a hot gases stream, a hydrogenation reactor configured to convert the hot gases stream to create a hydrogenation effluent comprising hydrogen sulfide, a process desuperheater configured to cool the hydrogenation effluent to generate a cooled effluent, and an absorber unit configured to absorb the hydrogen sulfide from the cooled effluent to produce a hydrogen sulfide recycle stream and a waste gas stream.

A process for producing hydrogen sulfide from hydrogen and elemental sulfur, comprising: bringing the sulfur into contact with a solid catalyst comprising at least one metal, chosen from metals from groups VIB and VIII of the Periodic Table of the Elements, in metal sulfide form, at a temperature ranging from 120 C. to 160 C.; circulating the mixture of sulfur and catalyst resulting from step (a) in a reaction zone, in which said mixture is brought into contact with hydrogen, the reaction zone having a temperature at the inlet point of the catalyst of greater than or equal to 150 C. and a temperature at the outlet point of the catalyst of less than or equal to 300 C., and a pressure of less than or equal to 3 bar; separating the catalyst and the gaseous effluents containing hydrogen sulfide; and recycling the catalyst to the step of bringing.

Embodiments of the disclosure provide a method and a Claus tail gas treatment system for sulfur recovery. A tail gas stream is fed to a hydrogenation reactor to produce a hydrogenated gas stream by converting sulfur-containing compounds to hydrogen sulfide. The hydrogenated gas stream is fed to a quench tower to produce a quenched gas stream by condensing and recovering liquid water via a water condensate stream. The quenched gas stream is fed to a first stage adsorption unit to produce a first outlet gas stream by separating water via a first byproduct stream from hydrogen sulfide, carbon dioxide, and nitrogen. The first outlet stream is fed to a second stage adsorption unit to produce a second outlet gas stream by separating carbon dioxide and nitrogen via a second byproduct stream. The second outlet stream includes hydrogen sulfide. The second outlet stream can be fed to a Claus unit.