Method for producing molecular halogen are disclosed, that include the steps of: oxidizing a halide to produce a mixture comprising one or more of a molecular halogen, a trihalide, and a halide; reducing a polysulfide comprising a higher rank polysulfide dianion to produce a lower rank polysulfide dianion; and recovering molecular halogen from the mixture comprising one or more of a molecular halogen, a trihalide, and a halide.

A composition containing nano-sulfur and an application thereof, the composition containing nano-sulfur contains nano-sulfur and further contains an anti-agglomeration agent used for preventing or delaying the agglomeration of the nano-sulfur, is provided. The composition containing nano-sulfur may be widely used for preparing toiletries for use on the surface of the skin on humans or animals, pharmaceutical compositions treating skin disorders, pesticides, preservatives for vegetables and fruits, additives for animal feed, additives for mold prevention in paint, mold prevention agents for textiles or (textile) mite-killing agents. The composition containing nano-sulfur is easy to prepare, and the nano-sulfur may remain in the nano state for a long time, reducing or even eliminating the occurrence of the agglomeration of the nano-sulfur, while achieving the goals of being applied in various products and preventing fungus by simply adding a very small amount.

Systems for improving metal leach kinetics and metal recovery during atmospheric or substantially atmospheric leaching of a metal sulfide are disclosed. In some embodiments, an oxidative leach circuit 200 may employ Mechano-Chemcial/Physico-Chemical processing means for improving leach kinetics and/or metal recovery. In preferred embodiments, the Mechano-Chemcial/Physico-Chemical means comprises various combinations of stirred-tank reactors 202 and shear-tank reactors 212. As will be described herein, the stirred-tank reactors 202 and shear-tank reactors 212 may be arranged in series and/or in parallel with each other, without limitation. In some non-limiting embodiments, a shear-tank reactor 212 may also be disposed, in-situ, within a stirred-tank reactor 202.

New dual temperature electrochemical methods and systems for the production of sodium metal from sodium polysulfides have been discovered. The technology provides high conductivity for sodium ions and extended service life for the electrochemical cell.

A method of improving metal leach kinetics and recovery during atmospheric or substantially atmospheric leaching of a metal sulfide is disclosed. In some embodiments, the method may comprise the step of processing a metal sulfide concentrate in a reductive activation circuit 220 that operates at a first redox potential, to produce a reductively-activated metal sulfide concentrate. The method may further comprise the step of subsequently processing the activated metal sulfide concentrate in an oxidative leach circuit 240 to extract metal values. In some disclosed embodiments, reductive activation steps and/or oxidative dissolution steps may employ mechano-chemical and/or physico-chemical processing of particles or agglomerates thereof. Reductive activation may be made prior to heap leaching or bio-leaching operations to improve metal extraction. Systems for practicing the aforementioned methods are also disclosed.

A composition containing nano-sulfur and an application thereof, the composition containing nano-sulfur contains nano-sulfur and further contains an anti-agglomeration agent used for preventing or delaying the agglomeration of the nano-sulfur, is provided. The composition containing nano-sulfur may be widely used for preparing toiletries for use on the surface of the skin on humans or animals, pharmaceutical compositions treating skin disorders, pesticides, preservatives for vegetables and fruits, additives for animal feed, additives for mold prevention in paint, mold prevention agents for textiles or (textile) mite-killing agents. The composition containing nano-sulfur is easy to prepare, and the nano-sulfur may remain in the nano state for a long time, reducing or even eliminating the occurrence of the agglomeration of the nano-sulfur, while achieving the goals of being applied in various products and preventing fungus by simply adding a very small amount.

The present disclosure provides a resource utilization method of crude sodium sulfate. The method comprises the following step: reducing the crude sodium sulfate to form a sodium sulfide solution; making the sodium sulfide solution perform a first reaction with chlorine to obtain sulfur and a sodium chloride solution; and electrolyzing the sodium chloride solution to obtain a sodium hydroxide solution and chlorine, and supplying the generated chlorine to the sodium sulfide solution to perform the first reaction. In the above resource utilization method of crude sodium sulfate, the sodium hydroxide is generated by combining relatively simple and mature process steps, and the crude sodium sulfate containing sodium chloride and sodium sulfate can be effectively converted to the sodium hydroxide in large market demand, so that complete recycling of sodium element and sulfur element is realized, which not only can fully utilize the resources and protect the environment, but also can create great economic benefits and environmental benefits, thus having a great significance to realize the green development of relevant industries.

The present disclosure provides a resource utilization method of crude sodium sulfate. The method comprises the following step: reducing the crude sodium sulfate to form a sodium sulfide solution; making the sodium sulfide solution perform a first reaction with chlorine to obtain sulfur and a sodium chloride solution; and electrolyzing the sodium chloride solution to obtain a sodium hydroxide solution and chlorine, and supplying the generated chlorine to the sodium sulfide solution to perform the first reaction. In the above resource utilization method of crude sodium sulfate, the sodium hydroxide is generated by combining relatively simple and mature process steps, and the crude sodium sulfate containing sodium chloride and sodium sulfate can be effectively converted to the sodium hydroxide in large market demand, so that complete recycling of sodium element and sulfur element is realized, which not only can fully utilize the resources and protect the environment, but also can create great economic benefits and environmental benefits, thus having a great significance to realize the green development of relevant industries.

Hydrogen sulfide is scrubbed from a gas stream to prepare dissolved alkali metal sulfide or hydrosulfide, which is used to prepare feed electrolyte solution for electrochemical processing to generate alkali metal hydroxide in catholyte and polysulfide in anolyte, which may be recovered from an electrochemical reactor and which may be subjected to further processing to precipitate elemental sulfur. Aqueous scrubbing solution may include alkali metal carbonate capture agent to capture hydrogen sulfide in alkali metal bicarbonate The gas stream may include carbon dioxide in addition to hydrogen sulfide, and a ratio of dissolved alkali metal carbonate to bicarbonate may be increased prior to electrochemical processing.

Hydrogen sulfide is scrubbed from a gas stream to prepare dissolved alkali metal sulfide or hydrosulfide, which is used to prepare feed electrolyte solution for electrochemical processing to generate alkali metal hydroxide in catholyte and polysulfide in anolyte, which may be recovered from an electrochemical reactor and which may be subjected to further processing to precipitate elemental sulfur. Aqueous scrubbing solution may include alkali metal carbonate capture agent to capture hydrogen sulfide in alkali metal bicarbonate The gas stream may include carbon dioxide in addition to hydrogen sulfide, and a ratio of dissolved alkali metal carbonate to bicarbonate may be increased prior to electrochemical processing.