Novel iron-phosphate nanoparticles have been synthesized here. These are less than 12 nanometers in dimension. They are deemed useful for remediation of heavy metals and radionuclides and can be applied to insitu remediation of contaminated soils and contaminated waters.

Novel iron-phosphate nanoparticles have been synthesized here. These are less than 12 nanometers in dimension. They are deemed useful for remediation of heavy metals and radionuclides and can be applied to insitu remediation of contaminated soils and contaminated waters.

A system for treating printed circuit board wastewater (PCB) includes a production system, a pretreatment system, a biochemical system, a recovery system and a concentrated water treatment system. The production system is configured for producing process water and auxiliary water from tap water. The pretreatment system is configured to pretreat different wastewater samples separately. The biochemical system is configured to decompose the pretreated wastewater. The recovery system is configured to treat wastewater from the pretreatment system and the biochemical system to obtain process water and feed concentrated water to the concentrated water treatment system. The concentrated water treatment system is configured to treat the concentrated water to meet a discharge standard. A treatment method for the PCB wastewater is also provided.

Contaminant-sequestering coatings include a network of hydrolyzed silane compounds including (i) a plurality of fluorinated functionalities, and (ii) a plurality of thiol functional groups are provided. The network of hydrolyzed silane compounds includes a fluorinated silane including (a) a hydrophilic polar head region. The polar head region includes one or multiple units of ethylene glycol (EG) functionality, (b) a fluorine-containing region, and (c) an anchor region including a silicon atom. The contaminant-sequestering coatings may sequester one or more per- and polyfluoroalkyl substances (PFAS), heavy metals, biological species, or any combination thereof.

Contaminant-sequestering coatings include a network of hydrolyzed silane compounds including (i) a plurality of fluorinated functionalities, and (ii) a plurality of thiol functional groups are provided. The network of hydrolyzed silane compounds includes a fluorinated silane including (a) a hydrophilic polar head region. The polar head region includes one or multiple units of ethylene glycol (EG) functionality, (b) a fluorine-containing region, and (c) an anchor region including a silicon atom. The contaminant-sequestering coatings may sequester one or more per- and polyfluoroalkyl substances (PFAS), heavy metals, biological species, or any combination thereof.

The present invention discloses a method for the separation of radionuclides from an aqueous radioactive waste solution, the method comprising: receiving of an aqueous radioactive waste solution, adding at least one zirconium salt to the aqueous radioactive waste solution, changing the pH of the radioactive waste solution to obtain a precipitate P, and separating the precipitate P from the radioactive waste solution. The present invention also discloses the use of zirconium salts, preferably zirconium oxychloride, zirconium nitrate or a zirconium oxynitrate or any mixture thereof, for the treatment of aqueous radioactive waste solution, preferably acidic or alkaline intermediate or low level radioactive waste solution, preferably an acidic intermediate and/or low level radioactive waste solution.

The present invention discloses a method for the separation of radionuclides from an aqueous radioactive waste solution, the method comprising: receiving of an aqueous radioactive waste solution, adding at least one zirconium salt to the aqueous radioactive waste solution, changing the pH of the radioactive waste solution to obtain a precipitate P, and separating the precipitate P from the radioactive waste solution. The present invention also discloses the use of zirconium salts, preferably zirconium oxychloride, zirconium nitrate or a zirconium oxynitrate or any mixture thereof, for the treatment of aqueous radioactive waste solution, preferably acidic or alkaline intermediate or low level radioactive waste solution, preferably an acidic intermediate and/or low level radioactive waste solution.

In order to solve the problem in the existing conventional water treatment process of low removal efficiency of heavy metal in water, especially lower efficiency for simultaneous removal of heavy metal pollutants during coexisting, a method is provided for removing heavy metal pollutants in water with divalent manganese strengthened ferrate: preparing a ferrate mother liquor having the concentration of 20-10,000 mmol/L; preparing a divalent manganese salt mother liquor having the concentration of 30-10,000 mmol/L; adding the divalent manganese salt mother liquor into water of the heavy metal pollutants; then adding the ferrate mother liquor, and reacting; and then adding a flocculant and precipitating, so that the removal rate of arsenate, chromium, thallium, antimony, chromium and molybdate in water is 90% or more, and the removal rate of heavy metal such as lead and cadmium is 85% or more.

In order to solve the problem in the existing conventional water treatment process of low removal efficiency of heavy metal in water, especially lower efficiency for simultaneous removal of heavy metal pollutants during coexisting, a method is provided for removing heavy metal pollutants in water with divalent manganese strengthened ferrate: preparing a ferrate mother liquor having the concentration of 20-10,000 mmol/L; preparing a divalent manganese salt mother liquor having the concentration of 30-10,000 mmol/L; adding the divalent manganese salt mother liquor into water of the heavy metal pollutants; then adding the ferrate mother liquor, and reacting; and then adding a flocculant and precipitating, so that the removal rate of arsenate, chromium, thallium, antimony, chromium and molybdate in water is 90% or more, and the removal rate of heavy metal such as lead and cadmium is 85% or more.

A metal-chelating resin includes (a) a compound represented by Formula (I):

##STR00001##

or a stereoisomeric form thereof or a salt thereof, wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.a, R.sup.b, R.sup.c and R.sup.d are as defined herein; and (b) an organic polymer resin having at least one complementary reactive functional group covalently linked with at least one linking group of the compound represented by Formula (I).