A method of improving leach kinetics and recovery during atmospheric or above-atmospheric leaching of a metal sulfide is disclosed. A system for practicing the aforementioned method is also disclosed. Apparatus for practicing the aforementioned method is also disclosed. A new composition of matter which is formed by the aforementioned method, and which may be utilized in the system and apparatus is further disclosed. The new composition of matter may exhibit improved leach kinetics, and may have some utility in the semi-conductor arts, including uses within photovoltaic materials.

This application pertains to methods of recovering metals from metal sulfides that involve contacting the metal sulfide with an acidic sulfate solution containing ferric sulfate and a reagent that has a thiocarbonyl functional group, wherein the concentration of reagent in the acidic sulfate solution is sufficient to increase the rate of metal extraction relative to an acidic sulfate solution that does not contain the reagent, to produce a pregnant solution containing the 10 metal ions.

A method for preparing the iron-based biochar material, the iron-based biochar material prepared there from and a method for controlling the heavy metal pollution in soil using the iron-based biochar material. For the iron-based biochar material of the present invention, by using a method of high-temperature carbonization, a biomass is used as a raw material and an iron-containing compound is add in the process of preparing biochar, wherein iron is incorporated in a specific ratio, to form the iron-based biochar material with a special structure and function. The material has a simple preparation process, low cost and a short production period; the prepared iron-based biochar material has an unique effect on the arsenic-cadmium combined pollution soil remediation, can effectively reduce the bioavailability of arsenic and cadmium in the soil, significantly reduces the arsenic and cadmium contents in the agricultural products planted in the arsenic-cadmium combined pollution soil, and has no toxic and side effects on the crops, is safe to apply and can be applied to the control of arsenic-cadmium combined pollution soil in a large scale.

A method for preparing the iron-based biochar material, the iron-based biochar material prepared there from and a method for controlling the heavy metal pollution in soil using the iron-based biochar material. For the iron-based biochar material of the present invention, by using a method of high-temperature carbonization, a biomass is used as a raw material and an iron-containing compound is add in the process of preparing biochar, wherein iron is incorporated in a specific ratio, to form the iron-based biochar material with a special structure and function. The material has a simple preparation process, low cost and a short production period; the prepared iron-based biochar material has an unique effect on the arsenic-cadmium combined pollution soil remediation, can effectively reduce the bioavailability of arsenic and cadmium in the soil, significantly reduces the arsenic and cadmium contents in the agricultural products planted in the arsenic-cadmium combined pollution soil, and has no toxic and side effects on the crops, is safe to apply and can be applied to the control of arsenic-cadmium combined pollution soil in a large scale.

This application pertains to methods of recovering metals from metal sulfides that involve contacting the metal sulfide with an acidic sulfate solution containing ferric sulfate and a reagent that has a thiocarbonyl functional group, wherein the concentration of reagent in the acidic sulfate solution is sufficient to increase the rate of metal ion extraction relative to an acidic sulfate solution that does not contain the reagent, to produce a pregnant solution containing the metal ions.

This application pertains to methods of recovering metals from metal sulfides that involve contacting the metal sulfide with an acidic sulfate solution containing ferric sulfate and a reagent that has a thiocarbonyl functional group, wherein the concentration of reagent in the acidic sulfate solution is sufficient to increase the rate of metal ion extraction relative to an acidic sulfate solution that does not contain the reagent, to produce a pregnant solution containing the metal ions.

This application pertains to methods of recovering metals from metal sulfides that involve contacting the metal sulfide with an acidic sulfate solution containing ferric sulfate and a reagent that has a thiocarbonyl functional group, wherein the concentration of reagent in the acidic sulfate solution is sufficient to increase the rate of metal ion extraction relative to an acidic sulfate solution that does not contain the reagent, to produce a pregnant solution containing the metal ions.

This application pertains to methods of recovering metals from metal sulfides that involve contacting the metal sulfide with an acidic sulfate solution containing ferric sulfate and a reagent that has a thiocarbonyl functional group, wherein the concentration of reagent in the acidic sulfate solution is sufficient to increase the rate of metal ion extraction relative to an acidic sulfate solution that does not contain the reagent, to produce a pregnant solution containing the metal ions.

The invention relates to a method for drying salts with a water of crystallisation content in convective apparatuses that can additionally be indirectly heated. The invention is primarily characterised in that the drying process takes place with a moisture content of the drying gas above a determined level. The gas surrounding the salt particles during the drying process therefore has a specific humidity. In this way, the rate of drying is positively influenced.

The invention relates to a method for drying salts with a water of crystallisation content in convective apparatuses that can additionally be indirectly heated. The invention is primarily characterised in that the drying process takes place with a moisture content of the drying gas above a determined level. The gas surrounding the salt particles during the drying process therefore has a specific humidity. In this way, the rate of drying is positively influenced.