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.

TiO.sub.2-supported catalysts include at least molybdenum or tungsten as active components for hydrotreating processes, in particular for the removal of sulfur and nitrogen compounds as well as metals out of crude oil fractions and for the hydrogenation of sulfur oxides.

Chemical probes and methods for detecting and/or quantifying hydrogen sulfide are disclosed. More particularly, this application discloses chemical probes and methods for their use for detecting and/or quantifying hydrogen sulfide in industrial and environmental samples and effluents, including samples of crude oil and sour water produced by petrochemical and other industrial processes.

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.

A method for desulfurization and dezincification of tailings includes the step of passing tap water into a high oxidation reduction electrocatalytic water equipment to reduce the pH value of tap water to 1-2, mixing a specific ratio of the pH value 1-2 acid electrocatalytic water with low-quality high-sulfur iron in the tailings, heating the mixture to let H.sup.+ in the acid electrocatalytic water be reacted with sulfur and zinc in the low-quality high-sulfur iron and to further cause generation of an ion state of hydrogen sulfide gas where the volatilization of water vapor effectively removes the sulfur and zinc elements in the low-quality high-sulfur iron and the hydrogen sulfide gas thus generated is collected.

To provide a hydrogen sulfide mixture hardly corroding metals. The hydrogen sulfide mixture contains hydrogen sulfide and water. The hydrogen sulfide mixture is filled into a filling container so that at least one part of the hydrogen sulfide mixture is liquid and the moisture concentration of a gaseous phase is 0.001 mol ppm or more and less than 75 mol ppm.

To provide a hydrogen sulfide mixture hardly corroding metals. The hydrogen sulfide mixture contains hydrogen sulfide and water. The hydrogen sulfide mixture is filled into a filling container so that at least one part of the hydrogen sulfide mixture is liquid and the moisture concentration of a gaseous phase is 0.001 mol ppm or more and less than 75 mol ppm.

A composite material is used for desulfurization. The composite material contains activated carbon, alkali metal oxides, silicon oxides, iron oxides, and rare earth element oxides. The weight ratio among the activated carbon, iron oxides and rare earth element oxides is 100:(0.5-5):(1-10). The composite material, used as a sulfur adsorbent, has a higher sulfur breakthrough capacity and desulfurization rate.

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 apparatus for in situ producing hydrogen sulfide (H.sub.2S) for laboratory use comprises a feed preparation section (A) for pre-treating a liquid feedstock with organic sulfur containing components; a hydrogen sulfide (H.sub.2S) production section (B) downstream of the feed preparation section (A) for producing hydrogen sulfide (H.sub.2S) from the organic sulfur containing components at elevated temperature; a separation section (C) downstream of the hydrogen sulfide (H.sub.2S) production section (B) for separating a vaporous portion of the liquid feedstock from a liquid portion at a temperature lower than the elevated temperature of section (B); a product analysis section (D) downstream of the separation section for analysing the amount of hydrogen sulfide (H.sub.2S) in the vaporous portion; a plurality of feeding lines for conveying the liquid feedstock; and a direct feeding line (E) from the separation section (C) for directly introducing the vaporous portion of the liquid feedstock into the laboratory setup.