A process of producing degassed liquid sulfur using process gas containing H.sub.2S to agitate the liquid sulfur being degassed while in contact with a degassing catalyst. Process gas is less costly and less complicated and quickly accomplishes substantial degassing rendering the liquid sulfur much safer in storage and transportation.

The present invention discloses a method and system of recovering elemental sulfur and regenerating the catalyst for a sulfur-deposited catalyst, including immersing the sulfur-deposited catalyst in the ammonium sulfide solution, the leaching reaction under normal pressure and temperature, replacing the ammonium sulfide solution and immersing again for extraction for the same time; collecting the leachate of the two steps, conducting gas stripping of the elemental sulfur by adopting the high-temperature nitrogen gas, condensing the tail gas of gas stripping, subjecting to a purification treatment and then discharging, with the liquor condensate being the ammonium sulfide solution. Finally, the solid in the leachate is filtered, washed and dried after the gas stripping to obtain the elemental sulfur; and the washing and drying of catalysts that has been subjected to the two times of immersion and extraction obtain the regenerated catalysts.

The present invention discloses a method and system of recovering elemental sulfur and regenerating the catalyst for a sulfur-deposited catalyst, including immersing the sulfur-deposited catalyst in the ammonium sulfide solution, the leaching reaction under normal pressure and temperature, replacing the ammonium sulfide solution and immersing again for extraction for the same time; collecting the leachate of the two steps, conducting gas stripping of the elemental sulfur by adopting the high-temperature nitrogen gas, condensing the tail gas of gas stripping, subjecting to a purification treatment and then discharging, with the liquor condensate being the ammonium sulfide solution. Finally, the solid in the leachate is filtered, washed and dried after the gas stripping to obtain the elemental sulfur; and the washing and drying of catalysts that has been subjected to the two times of immersion and extraction obtain the regenerated catalysts.

The present invention discloses a method and system of recovering elemental sulfur and regenerating the catalyst for a sulfur-deposited catalyst, including immersing the sulfur-deposited catalyst in the ammonium sulfide solution, the leaching reaction under normal pressure and temperature, replacing the ammonium sulfide solution and immersing again for extraction for the same time; collecting the leachate of the two steps, conducting gas stripping of the elemental sulfur by adopting the high-temperature nitrogen gas, condensing the tail gas of gas stripping, subjecting to a purification treatment and then discharging, with the liquor condensate being the ammonium sulfide solution. Finally, the solid in the leachate is filtered, washed and dried after the gas stripping to obtain the elemental sulfur; and the washing and drying of catalysts that has been subjected to the two times of immersion and extraction obtain the regenerated catalysts.

The present invention discloses a method and system of recovering elemental sulfur and regenerating the catalyst for a sulfur-deposited catalyst, including immersing the sulfur-deposited catalyst in the ammonium sulfide solution, the leaching reaction under normal pressure and temperature, replacing the ammonium sulfide solution and immersing again for extraction for the same time; collecting the leachate of the two steps, conducting gas stripping of the elemental sulfur by adopting the high-temperature nitrogen gas, condensing the tail gas of gas stripping, subjecting to a purification treatment and then discharging, with the liquor condensate being the ammonium sulfide solution. Finally, the solid in the leachate is filtered, washed and dried after the gas stripping to obtain the elemental sulfur; and the washing and drying of catalysts that has been subjected to the two times of immersion and extraction obtain the regenerated catalysts.

This invention provides a hydrometallurgical process for extracting one or more saleable products from a sulphate or chloride pregnant leach solution (PLS), or both. The products may be any one or more of the products selected from the group consisting of: precious metals including platinum group metals (PGMs), gold and silver, base metals, and rare metal elements, and metal cathodes, powders, salts or precipitates thereof; sulphur; hydrochloric acid (HCl); calcium; and silica.

This invention provides a hydrometallurgical process for extracting one or more saleable products from a sulphate or chloride pregnant leach solution (PLS), or both. The products may be any one or more of the products selected from the group consisting of: precious metals including platinum group metals (PGMs), gold and silver, base metals, and rare metal elements, and metal cathodes, powders, salts or precipitates thereof; sulphur; hydrochloric acid (HCl); calcium; and silica.