Abstract: 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.

Abstract: The present invention relates to a method for limiting the emission of dust from catalyst grains. Said method comprises the following two consecutive steps: a first step of performing a heat treatment of the catalyst grains at a temperature no lower than 100° C., followed by a second step of coating the surface of the catalyst grains by placing same in contact with one or more coating materials having a melting point T no lower than 45° C. and which are injected in a solid state, said second step being carried out with no further addition of heat, at a temperature of T?60° C. to T?1° C., while remaining no lower than 40° C.

Abstract: 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.

Abstract: The present invention relates to a method for limiting the emission of dust from catalyst grains. Said method comprises the following two consecutive steps: a first step of performing a heat treatment of the catalyst grains at a temperature no lower than 100° C., followed by a second step of coating the surface of the catalyst grains by placing same in contact with one or more coating materials having a melting point T no lower than 45° C. and which are injected in a solid state, said second step being carried out with no further addition of heat, at a temperature of T?60° C. to T?1° C., while remaining no lower than 40° C.

Abstract: A process and apparatus for extraction of zinc from a material containing one or more iron oxides and zinc oxide which facilitate heating a composite body of the material and a carbonaceous material in a reduction zone. The reduction zone contains a reducing atmosphere at a temperature insufficient to effect melting of the iron in the material but at a temperature and for a time sufficient to form a reductant from the carbonaceous material and to reduce a predetermined amount of the zinc oxide to zinc vapor. The process and apparatus also facilitate collecting the zinc vapor and cooling it to form liquefied or solid zinc.

Abstract: A cavity former (10) for forming one or more cavities in a concrete slab, includes a hollow body about which, during use of the former, poured concrete flows and subsequently cures to form a concrete slab in which the hollow body defines a cavity. A plurality of flanges (20, 21) projects from at least two sides of the body to define floors for respective channels adjacent the sides of the body. A plurality of supports (50, 51, 52 and 53) is integrated with and outstanding from the hollow body and/or flanges to support reinforcement mesh above the body and elongated slab reinforcement in the channels. Respective co-operable formations are disposed on the flanges and respective further sides of the body whereby respective pairs of the cavity formers may be located and relatively positioned together by the formations with one cavity former resting on a flange of the other, whereby to define the channels, which channels receive the poured concrete.

Abstract: A process and apparatus for extraction of zinc from a material containing one or more iron oxides and zinc oxide which facilitate heating a composite body of the material and a carbonaceous material in a reduction zone. The reduction zone contains a reducing atmosphere at a temperature insufficient to effect melting of the iron in the material but at a temperature and for a time sufficient to form a reductant from the carbonaceous material and to reduce a predetermined amount of the zinc oxide to zinc vapour. The process and apparatus also facilitate collecting the zinc vapour and cooling it to form liquefied or solid zinc.