Provided is a method for inhibiting extractant degradation in the DSX process through the manganese extraction control, the method comprising: (a) stirring DSX solvent and DSX feed solution, which is a solution containing a valuable metal from which iron has been removed in an agitator, in which soda ash (Na.sub.2CO.sub.3) is further added to maintain a constant pH; and (b) scrubbing the manganese from the DSX solvent, extracted in step (a).

A method for preparing nickel/manganese/lithium/cobalt sulfate and tricobalt tetraoxide from battery wastes adopts the following process: dissolving battery wastes with acid, removing iron and aluminum, removing calcium, magnesium and copper, carrying extraction separation, and carrying out evaporative crystallization to prepare nickel sulfate, manganese sulfate, lithium sulfate, cobalt sulfate or/and tricobalt tetraoxide. By using the method, multiple metal elements, such as nickel, manganese, lithium and cobalt, can be simultaneously recovered from the battery wastes, the recovered products are high in purity and can reach battery grade, battery-grade tricobalt tetraoxide can also be directly produced. The method is simple in process, low in energy consumption and free in exhaust gas pollution, and can realize zero release of wastewater.

A method for preparing nickel/manganese/lithium/cobalt sulfate and tricobalt tetraoxide from battery wastes adopts the following process: dissolving battery wastes with acid, removing iron and aluminum, removing calcium, magnesium and copper, carrying extraction separation, and carrying out evaporative crystallization to prepare nickel sulfate, manganese sulfate, lithium sulfate, cobalt sulfate or/and tricobalt tetraoxide. By using the method, multiple metal elements, such as nickel, manganese, lithium and cobalt, can be simultaneously recovered from the battery wastes, the recovered products are high in purity and can reach battery grade, battery-grade tricobalt tetraoxide can also be directly produced. The method is simple in process, low in energy consumption and free in exhaust gas pollution, and can realize zero release of wastewater.

Catalyst supports, supported catalysts, and a method of preparing and using the catalysts for the demetallation of metal-containing heavy oil feedstocks are disclosed. The catalyst supports comprise alumina and 5 wt % or less titania. Catalyst prepared from the supports have at least 30 to 80 volume percent of its pore volume in pores having a diameter of between 200 and 500 angstroms. Catalysts in accordance with the invention exhibit improved catalytic activity and stability to remove metals from heavy feedstocks during a hydroconversion process. The catalysts also exhibit increased sulfur and MCR conversion.

A process for purifying a manganese sulfate solution and precipitating high purity manganese sulfate monohydrate crystals. The concentration of manganese sulfate is increased and calcium and magnesium are removed by precipitating calcium and magnesium fluoride, which are separated from the concentrated solution to produce a clarified solution. In a first crystallization step, the clarified solution is combined with a recycled manganese sulfate solution and manganese sulfate seed crystals and the mixture is heated to produce a crystal suspension. Manganese sulfate crystals are separated and the remaining solution is used to prepare solid manganese fluoride, which is separated and returned to the process to remove calcium and magnesium. The manganese sulfate crystals are redissolved in water. Undissolved solids are removed to produce a second clarified manganese sulfate solution. In a second crystallization step the second clarified solution is combined with manganese sulfate monohydrate seed crystals, which are heated and mixed to produce a manganese sulfate monohydrate crystal product in a saturated manganese sulfate solution, from which the final high purity manganese sulfate monohydrate crystals are separated.

A process for purifying a manganese sulfate solution and precipitating high purity manganese sulfate monohydrate crystals. The concentration of manganese sulfate is increased and calcium and magnesium are removed by precipitating calcium and magnesium fluoride, which are separated from the concentrated solution to produce a clarified solution. In a first crystallization step, the clarified solution is combined with a recycled manganese sulfate solution and manganese sulfate seed crystals and the mixture is heated to produce a crystal suspension. Manganese sulfate crystals are separated and the remaining solution is used to prepare solid manganese fluoride, which is separated and returned to the process to remove calcium and magnesium. The manganese sulfate crystals are redissolved in water. Undissolved solids are removed to produce a second clarified manganese sulfate solution. In a second crystallization step the second clarified solution is combined with manganese sulfate monohydrate seed crystals, which are heated and mixed to produce a manganese sulfate monohydrate crystal product in a saturated manganese sulfate solution, from which the final high purity manganese sulfate monohydrate crystals are separated.

A method for producing manganese(II) sulfate monohydrate includes a pulverization and washing step of pulverizing and washing a manganese-containing by-product, a leaching step of leaching the pulverized manganese-containing by-product after the pulverization and washing step to produce a leachate, a neutralization step of neutralizing the leachate produced in the leaching step, an impurity removal step of removing impurities from the leachate neutralized in the neutralization step, a solvent extraction step of recovering manganese in the form of an aqueous solution of manganese sulfate from a process liquid subjected to the impurity removal step by using a solvent extraction method, and a crystallization step of producing manganese(II) sulfate monohydrate by evaporating and concentrating the aqueous solution of manganese sulfate produced in the solvent extraction step.

A method for producing manganese(II) sulfate monohydrate includes a pulverization and washing step of pulverizing and washing a manganese-containing by-product, a leaching step of leaching the pulverized manganese-containing by-product after the pulverization and washing step to produce a leachate, a neutralization step of neutralizing the leachate produced in the leaching step, an impurity removal step of removing impurities from the leachate neutralized in the neutralization step, a solvent extraction step of recovering manganese in the form of an aqueous solution of manganese sulfate from a process liquid subjected to the impurity removal step by using a solvent extraction method, and a crystallization step of producing manganese(II) sulfate monohydrate by evaporating and concentrating the aqueous solution of manganese sulfate produced in the solvent extraction step.

A method for preparing nickel/manganese/lithium/cobalt sulfate and tricobalt tetraoxide from battery wastes adopts the following process: dissolving battery wastes with acid, removing iron and aluminum, removing calcium, magnesium and copper, carrying extraction separation, and carrying out evaporative crystallization to prepare nickel sulfate, manganese sulfate, lithium sulfate, cobalt sulfate or/and tricobalt tetraoxide. By using the method, multiple metal elements, such as nickel, manganese, lithium and cobalt, can be simultaneously recovered from the battery wastes, the recovered products are high in purity and can reach battery grade, battery-grade tricobalt tetraoxide can also be directly produced. The method is simple in process, low in, energy consumption and free in exhaust gas pollution, and can realize zero release of wastewater.

A method for preparing nickel/manganese/lithium/cobalt sulfate and tricobalt tetraoxide from battery wastes adopts the following process: dissolving battery wastes with acid, removing iron and aluminum, removing calcium, magnesium and copper, carrying extraction separation, and carrying out evaporative crystallization to prepare nickel sulfate, manganese sulfate, lithium sulfate, cobalt sulfate or/and tricobalt tetraoxide. By using the method, multiple metal elements, such as nickel, manganese, lithium and cobalt, can be simultaneously recovered from the battery wastes, the recovered products are high in purity and can reach battery grade, battery-grade tricobalt tetraoxide can also be directly produced. The method is simple in process, low in, energy consumption and free in exhaust gas pollution, and can realize zero release of wastewater.