A method for efficiently removal of oxidised selenium from liquid, such as FGD wastewater. The method involves adding a non-iron-based reducing agent (e.g. sodium dithionite) and preferably Fe(II) ions to the liquid at a pH of above 7.5 or 8 and precipitating elemental selenium from the liquid.

A method for efficiently removal of oxidised selenium from liquid, such as FGD wastewater. The method involves adding a non-iron-based reducing agent (e.g. sodium dithionite) and preferably Fe(II) ions to the liquid at a pH of above 7.5 or 8 and precipitating elemental selenium from the liquid.

A reactor system for decomposing at least one of a per- or polyfluoroalkyl substance (PFAS) is provided. The system includes a material having an interior surface that defines a compartment; a subaqueous liquid in the compartment; and an electron donor in the subaqueous liquid, the electron donor configured to release a hydrated electron upon ultraviolet (UV) irradiation. The reactor system is configured so that when the electron donor releases a hydrated electron into the subaqueous liquid, the hydrated electron has a longer lifespan relative to an electron released in normal bulk phase water, and when a PFAS is present within the subaqueous liquid, the hydrated electron is capable of reductively defluorinating the PFAS and to generate fluoride ions (F). A method of operating the system to decompose PFAS is also provided.

A reactor system for decomposing at least one of a per- or polyfluoroalkyl substance (PFAS) is provided. The system includes a material having an interior surface that defines a compartment; a subaqueous liquid in the compartment; and an electron donor in the subaqueous liquid, the electron donor configured to release a hydrated electron upon ultraviolet (UV) irradiation. The reactor system is configured so that when the electron donor releases a hydrated electron into the subaqueous liquid, the hydrated electron has a longer lifespan relative to an electron released in normal bulk phase water, and when a PFAS is present within the subaqueous liquid, the hydrated electron is capable of reductively defluorinating the PFAS and to generate fluoride ions (F). A method of operating the system to decompose PFAS is also provided.

The crude oil sludge treatment agent is mixed with crude oil sludge and water and used for treatment of the crude oil sludge under alkali conditions. The crude oil sludge treatment agent contains green rust. The crude oil sludge treatment agent may further contain either or both a metal and a metal ferrite. The metal and the metal of the metal ferrite are one or more selected from the group consisting of aluminum, yttrium, zinc, copper, tin, chromium and silicon. The crude oil sludge treatment agent may also contain one or more selected from the group consisting of aluminum ferrite, yttrium ferrite and zinc ferrite. The crude oil sludge treatment method includes a mixing step in which crude oil sludge, water and green rust are mixed under alkali conditions.

An improved method for treating ordinary tap water to create an enhanced water composition for watering plants which can remove fluoride and chlorides from the tap water, and finally, to treat the enhanced water composition to provide a preferred pH level that is ideal for growing plants, and particularly medically grown cannabis, in order to enhance the uptake of certain nutrients for these plants.

An improved method for treating ordinary tap water to create an enhanced water composition for watering plants which can remove fluoride and chlorides from the tap water, and finally, to treat the enhanced water composition to provide a preferred pH level that is ideal for growing plants, and particularly medically grown cannabis, in order to enhance the uptake of certain nutrients for these plants.

The invention provides a method for preparing drinking weak alkali water and strontium-rich electrolyte raw water from distilled water obtained in the process of producing salt from well and mine brine, which comprises procedures of pressure reduction treatment, primary filtration, membrane separation treatment, activated carbon adsorption treatment, secondary filtration treatment, sterilization and disinfection treatment and the like on the salt-making distilled water in sequence so as to remove insoluble solid impurities, sulfides, microorganisms and other substances in the raw water, and separate or enrich ions, thereby preparing the weak alkali water suitable for drinking and the strontium-rich electrolyte raw water capable of being used for functional beverage production. The method provided by the invention can not only realize the comprehensive utilization of resources, but also obtain new products, significantly improving the economical efficiency of the process.

The presently disclosed subject matter is generally directed to a system and method of reducing, reacting, and/or removing an oxidant or unwanted chemical species from a chemical stream. Particularly, the system and method include the use of one or more reductants that react with the undesired chemical species. The reductant and the chemical stream are added to a reactor and allowed to react for a desired amount of time. The reductant will reduce, react with, and/or remove the chemical species from the stream. The excess reductant and reaction products are then removed from the reactor, as described in more detail herein below.

The present disclosure provides systems and methods for degrading per- and poly-fluoroalkyl substances (PFAS) using hydrated electrons generated in an ultraviolet (UV)/sulfite system. These systems and methods may be used, e.g., to remediate wastewater by destroying PFAS and co-contaminants such as chlorinated volatile organic compounds (CVOCs).