Processes are provided for the kinetically efficient reduction of selenate species to selenide species using chromous ions in acidic solution. This reduction may advantageously be carried out in the presence of sulphate species, with selective selenate reduction in preference to the reduction of sulfate. The reduced selenate may be removed from the chromous-treated solution, for example by precipitation of a copper-selenide solid. The chromic ions formed by reaction of chromous ions in the reduction of selenate may also be removed from solution, for example by addition of a base to form an insoluble chromic hydroxide solid. The chromic hydroxide may be recycled to regenerate chromous ions, for example by electrolysis. In this way, systems are provided for continuously removing dissolved selenium from wastewater streams.

A multi-copolymer, methods for producing the same and using thereof in wastewater treatment application are provided. The method includes pre-mixing by mass 10-30 parts by mass of alkenyl succinic anhydrides, 10-30 parts of vinylbenzyltrimethylammonium chloride, and 10-30 parts of dimethylaminoethyl methacrylate with water to form a first mixture; reacting the first mixture comprising passing thereof through inert gases to provide reflux protection, and adding by mass 10-30 parts of vinyl acetate and 10-30 parts of acrylamide to form a second mixture, followed by heating the second mixture and adding an initiator therein to initiate the reaction. The present invention is simple, at low cost, safe, non-toxic, environmentally friendly, easy to operate, with a better water purification efficiency than that of conventional macromolecule flocculants, multi-functional, good product stability, strong adsorption bridging ability, less dosage requirement for the water treatment agent, and results in a sturdy sludge cake and easily separated flocs.

An apparatus for the treatment of acid mine drainage and selective recovery of at least one of metals, critical elements, sulphuric acid and water is disclosed. The apparatus includes at least one electrochemical reactor, at least one catholyte reservoir and at least one anolyte reservoir for containing the acid mine drainage and a buffer, respectively. The reservoirs are in fluid communication with the at least one electrochemical reactor. The apparatus also includes at least one sensor for monitoring a pH of a contents of the reactor; and a power source for supplying an electrical current to the at least one electrochemical reactor. The electrical current is supplied until a predetermined pH is reached for the selective recovery of the at least one of metals, critical elements, sulphuric acid and water. A process for the treatment of acid mine drainage is also disclosed.

A crosslinked resin made up of polymerized units of a linear polyamine with at least 3 primary and/or secondary amine functionalities and a bisacrylamide. The crosslinked polymers are porous spherical particles with a BET surface area in the range of 50-120 m.sup.2/g. A method of the synthesizing the crosslinked polymer is specified. A method for using the crosslinked resin as an adsorbent material in removing pollutants including organic dyes (e.g. Congo red, Rhodamine B) and heavy metals from an aqueous solution or an industrial wastewater sample is also described.

Disclosed is the use of a composite for extracting one or more metal or contaminating chemical species from an aerial or aqueous medium by selective binding, the composite including at least one porous template functionalized by at least one polymer, the polymer including one of the following chemical functions: primary, secondary or tertiary amine, amide, nitrile, pyridine, pyrole, thiol, thiolether, thiophene, thiadiazole, alcohol/hydroxyl, phenol, catechol, pyragalol, carboxylic acid, aldehyde, ester, acyl, crown ether, phosphate, phosphoryl, epoxide, halogen, haloalkane.

Iron electrocoagulation (Fe-EC) reactors for removing contaminants from water comprising an assembly of spiral-wound or folded iron-containing anode and cathode plates separated with perforated insulating spacers, or an oxidant to accelerate oxidation of Fe(II) ions released from the anode to obtain Fe(III) ions, and/or to oxidize the contaminant.

There is provided microbial compositions and methods for producing thereof and use of compositions thereof in treatment of contaminated soil, water, and/or surfaces. In one aspect, there is provided method for reducing microbial contamination of a microbial contaminated body, the method comprises: inactivating resident vegetative microbiology from an extract obtained from a contaminated of body to inactivate the resident vegetative microbiology in the extract, selecting one or more soil-based microbes suitable for growth in the contaminated body, growing the one or more soil-based microbes with the inactivated extract to allow the one or more soil-based microbes to adapt to the inactivated extract, releasing the one or more soil-based microbes into the contaminated body where the one or more soil-based microbes dominate and reduce microbial contamination of the microbial contaminated body.

A treatment solution and method for removing heavy metal contaminants and oxyanion contaminants from an aqueous solution by promoting the affinity of precipitating the contaminants. The method adjusts the pH and the ORP of the contaminated aqueous solution by applying FeCl.sub.2 and/or NaOH reducing agents, and using and applying a titania-based treatment solution of TiO(SO.sub.4), H.sub.2SO.sub.4, and FeSO.sub.4.

The present disclosure relates to the field of resource-oriented utilization technologies for wastewater salt muds and more particular to a resource-oriented utilization method for a high-salt salt mud containing sodium chloride and sodium sulfate. The method includes: performing two stages of oxidation, i.e. Fenton-like treatment and chlorine dioxide treatment, in sequence on a salt mud solution, and then replacing a sodium salt with an ammonium salt to prepare a pure alkali and a mixed ammonium salt. In the method, multi-stage oxidation process is performed to effectively use ingredients such as sodium chloride and sodium sulfate so as to thoroughly eliminate organic matters and heavy metals in the high-salt salt mud, and achieve resource-oriented utilization of the salt mud, thus saving burial treatment costs, and producing good economic benefits as well as good environmental benefits.

A composite for adsorption of metal ions including silica microparticles, graphene oxide sheets, and polyaniline is provided. The graphene oxide sheets and polyaniline are distributed on a surface of the silica microparticles. Methods for removing cationic and anionic metal ions from a solution such as wastewater are also provided.