Treatment of environmental contaminants

Abstract

Contaminants, such as volatile organic compounds, are removed from an environmental medium, such as contaminated soil, rock, groundwater, waste water and the like, by treatment with a combination of a persulfate, such as a sodium persulfate, and hydrogen peroxide.

1 . A method for oxidizing a contaminant present in an environmental medium, said method comprising contacting the contaminant with a composition comprising a persulfate and hydrogen peroxide.  
   
   
       2 . The method of  claim 1 , wherein the persulfate is a monopersulfate or a dipersulfate.  
   
   
       3 . The method of  claim 1 , wherein the persulfate is sodium base, ammonium base, or potassium base.  
   
   
       4 . The method of  claim 1  wherein the persulfate is sodium persulfate.  
   
   
       5 . The method of  claim 1  wherein the mole ratio of persulfate to hydrogen peroxide is equal to from 1:20 to 20:1.  
   
   
       6 . The method of  claim 1  wherein the mole ratio of persulfate to hydrogen peroxide is equal to from 1:10 to 10:1.  
   
   
       7 . The method of  claim 1  wherein the persulfate and hydrogen peroxide are applied simultaneously to the medium.  
   
   
       8 . The method of  claim 1  wherein the persulfate and hydrogen peroxide are applied sequentially to the medium.  
   
   
       9 . The method of  claim 1  wherein the persulfate is applied to the medium prior to the application of the hydrogen peroxide.  
   
   
       10 . The method of  claim 1  wherein the hydrogen peroxide is applied to the medium prior to the application of the persulfate.  
   
   
       11 . The method of  claim 1  wherein the persulfate and hydrogen peroxide are applied to the medium sequentially in repeated applications.  
   
   
       12 . The method of  claim 11  wherein the repeated sequential additions of persulfate and hydrogen peroxide occur continuously.  
   
   
       13 . The method of  claim 11  wherein the repeated sequential additions of persulfate and hydrogen peroxide are separated by time intervals.  
   
   
       14 . The method of  claim 1  wherein the environmental medium is selected from soil, rock, groundwater, wastewater and process water.  
   
   
       15 . The method of  claim 1 , wherein the oxidation is performed in situ or ex situ.  
   
   
       16 . The method of  claim 1 , wherein the composition is introduced into the environmental medium in sufficient quantities and under conditions to oxidize substantially all of the contaminants in the medium.  
   
   
       17 . The method of  claim 1  where the composition also includes an activator.  
   
   
       18 . The method of  claim 17  where the activator is a divalent or trivalent transition metal.  
   
   
       19 . The method of  claim 18  wherein the activator is a divalent transition metal selected from Fe (II), Cu (II), Mn (II) or Zn (II).  
   
   
       20 . The method of  claim 18  wherein the activator is a trivalent transition metal, iron (III).  
   
   
       21 . The method of  claim 17  wherein the activator is a divalent or trivalent transition metal combined with a chelating agent.  
   
   
       22 . The method of  claim 21  wherein the activator is a divalent transition metal selected from iron (II), Cu (II), Mn (II) or Zn (II).  
   
   
       23 . The method of  claim 21  wherein the activator is a trivalent transition metal selected from iron (III).  
   
   
       24 . The method of  claim 21  wherein the chelating agent is selected from ethylenediamine tetraacetic acid, citric acid, phosphate, phosphonate, catechol or nitroacetic acid.  
   
   
       25 . A composition suitable for use in treating a contaminant present in an environmental medium, said composition comprising a persulfate and hydrogen peroxide.  
   
   
       26 . The composition of  claim 25 , wherein the persulfate is a monopersulfate or a dipersulfate.  
   
   
       27 . The composition of  claim 25 , wherein the persulfate is sodium base, ammonium base, or potassium base.  
   
   
       28 . The composition of  claim 25 , wherein the persulfate is sodium persulfate.  
   
   
       29 . The composition of  claim 25  wherein the mole ratio of persulfate to hydrogen peroxide is equal to from 1:20 to 20:1.  
   
   
       30 . The composition of  claim 25  wherein the mole ratio of persulfate to hydrogen peroxide is equal to from 1:10 to 10:1.  
   
   
       31 . The composition of  claim 25  further including an activator.  
   
   
       32 . The composition of  claim 31  wherein the activator is a divalent or trivalent transition metal.  
   
   
       33 . The composition of  claim 32  wherein the activator is a divalent transition metal selected from Fe (II), Cu (II), Mn (II) or Zn (II).  
   
   
       34 . The composition of  claim 32  wherein the activator is a trivalent transition metal, Fe (III).  
   
   
       35 . The composition of  claim 31  wherein the activator is a divalent or trivalent transition metal combined with a chelating agent.  
   
   
       36 . The composition of  claim 35  wherein the activator is a divalent transition metal selected from Fe (II), Cu (II), Mn (II) or Zn (II).  
   
   
       37 . The composition of  claim 35  wherein the activator is a trivalent metal, Fe (III).  
   
   
       38 . The composition of  claim 35  wherein the chelating agent is selected from ethylenediamine tetraacetic acid, citric acid, phosphate, catechol or nitroacetic acid.