Dual function proppants

A method to remove contaminants from a fractured well stratum or well, said method comprising:

• introducing into said stratum or said well a formulation that comprises first solid particulates associated with a contaminant removal component in a sufficient quantity to remove at least a portion of the contaminants in fluids in said stratum or well, wherein said contaminant removal component comprises a polymeric coating on said first solid particulates that comprises a contaminant removal chemical or biological agent with a functional affinity for impurities in said stratum, wherein said chemical comprises at least one sulfonic acid, carboxylic acid, phenolic, amino acid, glycolamine, polyamine, quaternary amine, or polyhydroxylic compound.

A solids formulation, said solids formulation comprising a plurality of first particulate solids associated with a contaminant removal component in sufficient quantity to remove at least a portion of contaminants in liquids issuing from a well,

• wherein said contaminant removal component comprises a polymeric coating disposed on said first particulate solids,
• wherein the coating comprises a contaminant removal chemical or biological agent with a functional affinity for impurities in said stratum,
• wherein said contaminant removal chemical or biological agent comprises at least one sulfonic acid, carboxylic acid, phenolic, amino acid, glycolamine, polyamine, quaternary amine, or polyhydroxylic compound.