Removal of very low concentrations of halogenated contaminants from industrial waste water involves use of regenerable adsorbents, especially molecular sieves or activated carbons

摘要

Pressureless removal from industrial waste water of halogenated contaminants (especially at the low concentrations left after physical or chemical treatment) by contacting with an H2O2 solution-regenerable adsorbent is such that hydrophilic and/or hydrophobic adsorbents or mechanical mixtures of e.g. molecular sieves and activated C are used in a specified manner. Pressureless removal from industrial waste water of halogenated contaminants (especially at the low concentrations left after physical or chemical treatment) by contacting with an H2O2 solution-regenerable adsorbent is such that hydrophilic and/or hydrophobic adsorbents or mechanical mixtures of e.g. molecular sieves and activated C are used as follows: (a) the water pH is set to above 7 to 12; (b) the amount of contaminant at the active centers of the adsorbent is increased by passing the water through an adsorber until break-through; (c) the contaminant is decomposed into CO2, water and halide with simultaneous regeneration with aqueous H2O2 solution; (d) the adsorbent is regenerated by elution with aqueous caustic soda to remove the remaining oxidation products; and (e) the used solution from step (c) is added into the waste water.