A method includes treating a first brine stream including a plurality of minerals with an anti-scalant to produce a treated brine. The first brine stream is provided by a wastewater treatment system. The method also includes directing the treated brine to a first nanofiltration (NF) system disposed downstream from and fluidly coupled to the wastewater treatment system, generating a first NF permeate stream and a first NF non-permeate stream from the treated brine in the first NF system, directing the first NF non-permeate stream to a mineral removal system disposed downstream from and fluidly coupled to the first NF system, and removing the plurality of minerals from the first NF non-permeate stream to generate a first overflow stream in the mineral removal system. The first overflow stream comprises at least a portion of the plurality of minerals. The method also includes routing a first portion of the first overflow stream to a hydrochloric acid (HCl) and sodium hydroxide (NaOH) production system disposed downstream from and fluidly coupled to the mineral removal system. The HCl and NaOH production system includes a second NF system that may receive the first portion of the first overflow stream and may generate a second brine stream from the first portion of the first overflow stream. The method further includes directing the second brine stream to a first electrodialysis (ED) system disposed within the HCl and NaOH production system and fluidly coupled to the second NF system. The first ED system may generate HCl and NaOH from the second brine stream.

A device and process for the separate removal of oppositely charged ions from electrolyte solutions and recombining them to form new chemical compositions. The invention provides the ability to create multiple ion flow channels and then form new chemical compositions therefrom. The process is accomplished by selectively combining oppositely charged ions of choice from different electrolyte solutions via the capacitive behavior of high electrical capacitance electrodes confined in insulated containers. Industrial plants employing the inventive process can have the flexibility to produce needed industrial chemical compounds such as Soda Ash, Caustic Soda, hydrochloric acid and chlorine gas, based on market demand, and can be located near points of consumption to significantly reduce transportation costs.

A device and process for the separate removal of oppositely charged ions from electrolyte solutions and recombining them to form new chemical compositions. The invention provides the ability to create multiple ion flow channels and then form new chemical compositions therefrom. The process is accomplished by selectively combining oppositely charged ions of choice from different electrolyte solutions via the capacitive behavior of high electrical capacitance electrodes confined in insulated containers. Industrial plants employing the inventive process can have the flexibility to produce needed industrial chemical compounds such as Soda Ash, Caustic Soda, hydrochloric acid and chlorine gas, based on market demand, and can be located near points of consumption to significantly reduce transportation costs.

The present invention concerns a method for the recovery of solvent in a process for preparation of regenerated cellulosic fibers using sodium hydroxide as solvent for cellulose dissolving in the manufacturing of a cellulose spinning dope wherein sodium hydroxide present in the spinning dope is at least partially recovered and recycled as sodium hydroxide from a cellulose fiber regeneration or cellulose coagulation step and wherein said cellulose fiber regeneration or cellulose coagulation step consists of a bath into which cellulose spinning dope is injected. Recovered sodium hydroxide may be directly or indirectly recycled from a cellulose fiber regeneration or cellulose coagulation step to a cellulose dissolving step.

The present invention concerns a method for the recovery of solvent in a process for preparation of regenerated cellulosic fibers using sodium hydroxide as solvent for cellulose dissolving in the manufacturing of a cellulose spinning dope wherein sodium hydroxide present in the spinning dope is at least partially recovered and recycled as sodium hydroxide from a cellulose fiber regeneration or cellulose coagulation step and wherein said cellulose fiber regeneration or cellulose coagulation step consists of a bath into which cellulose spinning dope is injected. Recovered sodium hydroxide may be directly or indirectly recycled from a cellulose fiber regeneration or cellulose coagulation step to a cellulose dissolving step.

A process for preparing metal oxide comprising (i) at least one metal chosen from nickel and cobalt and optionally (ii) at least one metal chosen from manganese, lithium and aluminum. The process comprising: reacting a metal sulfate comprising (i) at least one metal chosen from nickel and cobalt and optionally (ii) at least one metal chosen from manganese, lithium and aluminum with lithium hydroxide and optionally a chelating agent to obtain a solid comprising a metal hydroxide comprising (i) at least one metal chosen from nickel and cobalt and optionally (ii) at least one metal chosen from manganese, lithium and aluminum, and a liquid comprising lithium sulfate, the metal sulfate comprising (i) at least one metal chosen from nickel and cobalt and optionally (ii) at least one metal chosen from manganese, lithium and aluminum; separating the liquid and the solid from one another to obtain the metal hydroxide; submitting the liquid comprising lithium sulfate to an electromembrane process for converting the lithium sulfate into lithium hydroxide; and reusing at least a first portion of said lithium hydroxide obtained by the electromembrane process for reacting with the metal sulfate; reacting at least a second portion of said lithium hydroxide obtained by the electromembrane process with the obtained metal hydroxide to obtain a mixture of metal hydroxides; and roasting said mixture of metal hydroxides to obtain the metal oxide.

A process for preparing metal oxide comprising (i) at least one metal chosen from nickel and cobalt and optionally (ii) at least one metal chosen from manganese, lithium and aluminum. The process comprising: reacting a metal sulfate comprising (i) at least one metal chosen from nickel and cobalt and optionally (ii) at least one metal chosen from manganese, lithium and aluminum with lithium hydroxide and optionally a chelating agent to obtain a solid comprising a metal hydroxide comprising (i) at least one metal chosen from nickel and cobalt and optionally (ii) at least one metal chosen from manganese, lithium and aluminum, and a liquid comprising lithium sulfate, the metal sulfate comprising (i) at least one metal chosen from nickel and cobalt and optionally (ii) at least one metal chosen from manganese, lithium and aluminum; separating the liquid and the solid from one another to obtain the metal hydroxide; submitting the liquid comprising lithium sulfate to an electromembrane process for converting the lithium sulfate into lithium hydroxide; and reusing at least a first portion of said lithium hydroxide obtained by the electromembrane process for reacting with the metal sulfate; reacting at least a second portion of said lithium hydroxide obtained by the electromembrane process with the obtained metal hydroxide to obtain a mixture of metal hydroxides; and roasting said mixture of metal hydroxides to obtain the metal oxide.

Processes for regenerating alkali process streams are disclosed herein, including streams containing sodium hydroxide, magnesium hydroxide, and combinations thereof. Systems for regenerating alkali process streams are disclosed herein, including streams containing sodium hydroxide, magnesium hydroxide, and combinations thereof.

Processes for regenerating alkali process streams are disclosed herein, including streams containing sodium hydroxide, magnesium hydroxide, and combinations thereof. Systems for regenerating alkali process streams are disclosed herein, including streams containing sodium hydroxide, magnesium hydroxide, and combinations thereof.

This invention relates to the regeneration of spent alkaline solutions, for example, alkaline electrolyte solutions used in metal/air batteries, specifically in aluminum/air batteries. The invention provides methods and systems to regenerate alkaline electrolyte solutions by adding water and optionally other solvents to spent electrolyte solutions, thus precipitating metal hydroxides from the spent electrolyte solution.