An object of the present invention is to provide a dispersant for treatment of water. The dispersant is used in a membrane separation process of water containing an organic compound having a phenolic hydroxy group and prevents a reduction in amount of the water permeating a separation membrane, which is caused by deposition of the organic compound onto the surface of the separation membrane. Provided are a dispersant for treatment of water containing an organic compound having a phenolic hydroxy group wherein the dispersant contains a polymer compound having a carbonyl group and a structure including a nitrogen atom bonded to a carbonyl carbon atom; and a method for treatment of water containing an organic compound having a phenolic hydroxy group, wherein the method includes adding the dispersant to the water.

The present invention refers to a process for the preparation of an aqueous solution comprising at least one earth alkali hydrogen carbonate and its uses.

A process for extracting a surfactant from a mixture using a boronic acid modified material.

An electrochemical device comprises a first type of membrane disposed between first and second reservoirs containing an input solution, and a second type of membrane, different from the first type, is disposed between a first redox-active electrolyte chamber and the first reservoir and disposed between a second redox-active electrolyte chamber and the second reservoir. The first type of membrane and one of the second type of membranes form a membrane pair and the pair has an area specific resistance below y=5065.3x.sup.31331.1x.sup.2+90.035x+39 Ohm cm.sup.2 when the pair is equilibrated in an electrolyte and for at least part of a range where 0<x<0.4 and x is the mass fraction of salt in the electrolyte.

A media mixture for water treatment is provided. The media mixture may comprise activated alumina in an amount of from about 7% to about 17% by volume of the media mixture, activated carbon in an amount of from about 17% to about 42% by volume of the media mixture, and zeolite in an amount of from about 17% to about 57% by volume of the media mixture.

Provided are systems and methods for removing per- and polyfluoroalkyl substances (PFAS) from a contaminated stream comprising: collecting a contaminated stream comprising one or more PFAS; concentrating the one or more PFAS of the contaminated stream to achieve a concentrated stream having greater than or equal to 0.01 wt. % PFAS; and removing the one or more PFAS of the concentrated stream by heating the concentrated stream in the presence of calcium oxide to produce calcium fluoride.

Provided herein are copolymers and copolymer compositions that are both hydrophilic and oleophobic. The copolymers include structural units derived from a fluoroalkyl monomer and a zwitterionic monomer. It further relates to membranes formed by coating a porous substrate with the copolymeric compositions. The copolymeric coating imparts hydrophilicity and oleophobicity/oil-tolerance to the membranes. The uses of such membranes as microfiltration membrane or ultrafiltration membrane are also provided.

An advanced defluoridation agent and a method for removing fluoride ions in fluorine-containing wastewater are provided. The advanced defluoridation agent includes 40-70 wt % of polyaluminum sulfate, 0.3-30 wt % of hydroxyapatite and deionized water supplemented to 100 wt %. Using the advanced defluoridation agent of the present disclosure to treat fluoride-containing wastewater can achieve increased defluorination efficiency, reduced electrical conductivity, and reduced sludge content, and a better defluorination effect. The concentration of fluoride ions is lower than 15 ppm after using the advanced defluoridation agent of the present disclosure.

A two-stage system and method for treating fluoride-containing wastewater are provided. The two-stage system includes a first concentration defluoridation section and a second concentration defluoridation section. In the first concentration defluoridation section, the first mixed wastewater containing high concentration of fluoride ions is mixed with calcium chloride and stirred in the second mixing tank to obtain the second mixed wastewater containing low-concentration fluoride ions; in the second concentration defluoridation section, the second mixed wastewater is mixed with an advanced defluoridation agent and stirred in the third mixing tank to form a third mixed wastewater; the third mixed wastewater is introduced into a flocculation tank from the third mixing tank; and polymer is added for flocculation and sedimentation, so as to discharge a sediment and a defluoridation wastewater, the fluoride ion of which is less than 15 ppm.

The present invention relates to a method for reduce treating ballast water which has been subjected to a biocidal treatment with a chlorine-based oxidizing agent or an oxygen-based oxidizing agent, by using a tablet or pellet of sodium sulfite.