Methods and systems for bioremediation of heavy metal contaminants in waste materials (e.g., sludge and combustion wastes from a coal-fixed power plant). The systems described in the present application include at least one waste treatment unit (e.g., a flue gas cleaner or a waste lagoon) that includes one or more selected bacterial strains disposed therein consume and/or reclaim at least a portion of the heavy metal in the combustion wastes. Methods include inoculating a waste treatment unit with one or more selected bacteria that consume and/or reclaim at least a portion of the heavy metal in the combustion wastes. Methods may include periodic reinoculation of the waste treatment unit with fresh bacteria and period recovery of the bacteria from the waste treatment unit.

The present invention relates to the use of particulate mineral material comprising barite for scavenging heavy metal anions from a liquid medium, wherein the heavy metal anions form water-insoluble barium salts with barium cations of the barite, and wherein the particulate mineral material has a specific surface area of from 0.1 m.sup.2/g to 100 m.sup.2/g, measured using nitrogen sorption and the BET method.

Provided is a method for treating a hexavalent chromium-containing aqueous solution by water treatment employing a titanium dioxide photocatalyst that is excellent in both photocatalytic activity and solid-liquid separation performance. The method according to the present disclosure includes the steps of: adding catalyst particles to the aqueous solution; reducing hexavalent chromium by irradiating the aqueous solution with light having a wavelength of 200 nanometers or more and 400 nanometers or less while stirring the catalyst particles in the aqueous solution; and stopping the stirring and separating the catalyst particles from the aqueous solution by sedimentation. Each catalyst particle is composed only of a titanium dioxide particle and a zeolite particle, the titanium dioxide particle is adsorbed on the outer surface of the zeolite particle, the zeolite particle has a silica/alumina molar ratio of 10 or more, and the catalyst particles are contained in the aqueous solution at a concentration of 0.4 grams/liter or more and 16 grams/liter or less.

A composition, process and apparatuses for removal of one or more contaminant anions from water are provided. In an embodiment, the process includes treating the water with a composition comprising a layered metal hydroxy salt, wherein the layered metal hydroxy salt is a compound comprising (a) a metal (b) a framework hydroxide, and (c) a replaceable anion.

Cross-linked tetrapolymers made up of different diallyl zwitterionic diallyl quaternary ammonium salt monomers, with one of them functioning as a cross-linking monomer. The cross-linked terpolymers include a repeating unit with multiple ligand centers that different metal ions can bind to. The cross-linked tetrapolymers are cationic, zwitterionic and anionic, and can be in either an acidic form or a basic form. A method of removing metal ions from an aqueous solution with these cross-linked tetrapolymers is also described.

A liquid filter article, including: a housing having an inlet, an outlet, and an adsorbent bed there between, the bed comprising: a first stage having a first adsorbent, the first adsorbent including an activated carbon honeycomb infused with a plurality of zero valent iron nanoparticles (“Fe-AC”); and a second stage having a second adsorbent, the second adsorbent being selected from iron oxide particles supported on activated carbon honeycomb (“FEOX-AC”), iron oxide particles supported on activated alumina honeycomb (“FeOX-AA”), or a combination thereof, wherein the first stage is in fluid communication with the second stage. Also disclosed is a method of using the liquid filter article to remediate heavy metals in water.

An insoluble thin hydroxide shell is synthesized on the surface of nanoscale zero-valent iron (NZVI), using a rate-controlled deprotonation method. The hydroxide coated NZVI remains suspended in aqueous phase better than the prior art and can be used to remove groundwater contaminants.

A polymeric hybrid particle or composition comprising of polymers, such as polystyrene or methylated polystyrenes with cyclic amines and their halogenated forms, and nanoparticles (NPs). The method for the preparation thereof and uses as nano-adsorbent, or a biocide, or a dual function combination of biocide and adsorbent for use in a fluid system for the purpose of purification or remediation are 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.

A process for purifying a diaryl carbonate, comprises introducing an aqueous stream to a diaryl carbonate stream that comprises a metal contaminant, wherein the aqueous stream reacts with the metal contaminant to form a precipitate; wherein introducing the aqueous stream to the diaryl carbonate stream results in introducing 100 to 10,000 ppm water based on the total composition of the diaryl carbonate stream and the aqueous stream; removing the precipitate via one or both of a separation column and a filter to result in a purified diaryl carbonate.