Abstract: The present embodiments generally relate to methods and compositions for the removal of selenium from a fluid in need of treatment, such as, for example, industrial wastewaters. The methods and compositions for the removal of selenium generally comprise the use of one or more coagulants, such as at least one iron-containing coagulant, and one or more reducing agents, such as at least one sodium sulfite-based reducing agent.

Abstract: Depressants comprising a polymer comprising: a) recurring units of one or more acrylamide monomers; b) recurring units of one or more monomers selected from hydroxyalkyl alkylacrylate, allyloxyalkyldiol, allyloxyethanol, trimethylolpropane allyl ether, and 2-hydroxy ethyl acrylate; and optionally, c) recurring units of one or more acrylic acid monomers are provided. Also disclosed are processes for enriching a desired mineral from an ore comprising the desired mineral and gangue, wherein the process comprises carrying out a flotation process in the presence of one or more of the depressants.

Abstract: Selective flocculants comprise a polymer comprising recurring units of one or more acrylamide monomers; recurring units of one or more monomers selected from hydroxyalkyl alkylacrylate, allyloxyalkyldiol, allyloxyethanol, trimethylolpropane allyl ether, and 2-hydroxy ethyl acrylate; and optionally, recurring units of one or more acrylic acid monomers. Also disclosed are processes for enriching a desired mineral from an ore comprising the desired mineral and gangue, wherein the process comprises carrying out a selective flocculation process in the presence of one or more of the selective flocculants.

Abstract: Methods for removing one or more contaminants from an aqueous stream comprising: adding one or more hydraulic binders and one or more promoters to the aqueous stream, and separating the contaminants from the aqueous stream are provided. The methods may be used for removing contaminants that are arsenic-based, selenium-based, cadmium-based, zinc-based, mercury-based, iron-based, chromium-based and/or phosphate-based.

Abstract: Methods for removing one or more contaminants from an aqueous stream comprising: adding a polymer comprising recurring units of one or more acrylamide monomers and recurring units of one or more monomers selected from hydroxyalkyl-methacrylates and allyloxyalkyldiols to the aqueous stream to form solidified contaminants; and separating the solidified contaminants from the aqueous stream are provided. The methods may be used for removing contaminants including zinc-, copper-, barium-, aluminum-, manganese-, cobalt-, and iron-based contaminants.

Abstract: Methods for removing one or more contaminants from an aqueous stream comprising: adding one or more hydraulic binders and one or more promoters to the aqueous stream, and separating the contaminants from the aqueous stream are provided. The methods may be used for removing contaminants that are arsenic-based, selenium-based, cadmium-based, zinc-based, mercury-based, iron-based, chromium-based and/or phosphate-based.