Process for the removal of endocrine disrupting compounds

Abstract

The present invention relates to the removal of endocrine disrupting compounds from an aqueous medium by adding surface-reacted natural calcium carbonate or an aqueous suspension comprising surface-reacted calcium carbonate and having a pH greater than 6.0 measured at 20° C., to the medium, wherein the surface-reacted calcium carbonate is a reaction product of natural calcium carbonate with carbon dioxide and one or more acids, the use of the surface-reacted natural calcium carbonate for the removal of endocrine disrupting compounds, as well as to a combination of a surface-reacted natural calcium carbonate and activated carbon for the removal of endocrine disrupting compounds.

1 - 20 . (canceled) 
     
     
         21 . A combination of surface-reacted natural calcium carbonate and activated carbon for the removal of EDCs from an aqueous medium, wherein the surface-reacted calcium carbonate is a reaction product of natural calcium carbonate with carbon dioxide and one or more acids, wherein the carbon dioxide is formed in situ by the acid treatment and/or is supplied from an external source. 
     
     
         22 . A composite of surface-reacted natural calcium carbonate and one or more EDCs removed from an aqueous medium, wherein the surface-reacted calcium carbonate is a reaction product of natural calcium carbonate with carbon dioxide and one or more acids, wherein the carbon dioxide is formed in situ by the acid treatment and/or is supplied from an external source. 
     
     
         23 . The composite according to  claim 22  further comprising activated carbon. 
     
     
         24 . The combination according to  claim 21 , wherein the surface-reacted natural calcium carbonate is prepared as an aqueous suspension having a pH of greater than 6.0, measured at 20° C. 
     
     
         25 . The combination according to  claim 21 , wherein the surface-reacted natural calcium carbonate is prepared as an aqueous suspension having a pH of greater than 6.5, measured at 20° C. 
     
     
         26 . The combination according to  claim 21 , wherein the surface-reacted natural calcium carbonate is prepared as an aqueous suspension having a pH of greater than 7.0, measured at 20° C. 
     
     
         27 . The combination according to  claim 21 , wherein the surface-reacted natural calcium carbonate is prepared as an aqueous suspension having a pH of greater than 7.5, measured at 20° C. 
     
     
         28 . The combination according to  claim 21 , wherein the natural calcium carbonate is selected from the group comprising marble, calcite, chalk and dolomite, limestone and mixtures thereof. 
     
     
         29 . The combination according to  claim 21 , wherein the acid has a pK a  at 25° C. of 2.5 or less. 
     
     
         30 . The combination according to  claim 21 , wherein the acid is selected from the group comprising hydrochloric acid, sulphuric acid, sulphurous acid, hydrosulphate, phosphoric acid, oxalic acid and mixtures thereof. 
     
     
         31 . The combination according to  claim 21 , wherein the natural calcium carbonate is reacted with the acid and/or the carbon dioxide in the presence of at least one silicate and/or silica, aluminium hydroxide, earth alkali metal aluminate, magnesium oxide, or mixtures thereof. 
     
     
         32 . The combination according to  claim 21 , wherein the natural calcium carbonate is reacted with the acid and/or the carbon dioxide in the presence of at least one silicate selected from the group comprising aluminium silicate, calcium silicate and alkali metal silicate. 
     
     
         33 . The combination according to  claim 21 , wherein the surface-reacted natural calcium carbonate has a specific surface area of from 5 m 2 /g to 200 m 2 /g, measured using nitrogen and the BET method according to ISO 9277. 
     
     
         34 . The combination according to  claim 21 , wherein the surface-reacted natural calcium carbonate has a specific surface area of from 20 m 2 /g to 80 m 2 /g, measured using nitrogen and the BET method according to ISO 9277. 
     
     
         35 . The combination according to  claim 21 , wherein the surface-reacted natural calcium carbonate has a specific surface area of from 30 m 2 /g to 60 m 2 /g, measured using nitrogen and the BET method according to ISO 9277. 
     
     
         36 . The combination according to  claim 21 , wherein the surface-reacted natural calcium carbonate has a mean grain diameter d 50  of from 0.1 to 50 μm, measured according to the sedimentation method. 
     
     
         37 . The combination according to  claim 21 , wherein the surface-reacted natural calcium carbonate has a mean grain diameter d 50  of from 0.5 to 25 μm, measured according to the sedimentation method. 
     
     
         38 . The combination according to  claim 21 , wherein the surface-reacted natural calcium carbonate has a mean grain diameter d 50  of from 0.8 to 20 μm, measured according to the sedimentation method. 
     
     
         39 . The combination according to  claim 21 , wherein the surface-reacted natural calcium carbonate has a mean grain diameter d 50  of from 1 to 10 μm, measured according to the sedimentation method. 
     
     
         40 . The combination according to  claim 21 , wherein the aqueous suspension of surface-reacted natural calcium carbonate is stabilized with one or more dispersants. 
     
     
         41 . The combination according to  claim 21 , wherein the surface-reacted natural calcium carbonate is used in powder form and/or in the form of granules. 
     
     
         42 . The combination according to  claim 21 , wherein the surface-reacted calcium carbonate is added to the aqueous medium containing one or more EDCs in a dosage (weight-based) of 10 2  to 10 9  times the mass of the EDC(s) in the aqueous medium. 
     
     
         43 . The combination according to  claim 21 , wherein the surface-reacted calcium carbonate is added to the aqueous medium containing one or more EDCs in a dosage (weight-based) of 2·10 4  to 10 6  times the mass of the EDC(s) in the aqueous medium. 
     
     
         44 . The combination according to  claim 21 , wherein the surface-reacted calcium carbonate is added to the aqueous medium containing one or more EDCs in a dosage (weight-based) of 10 4  to 3·10 5  times the mass of the EDC(s) in the aqueous medium. 
     
     
         45 . The combination according to  claim 21 , wherein the pH of the aqueous medium is adjusted to a value of >6 prior to the addition of the surface-reacted natural calcium carbonate. 
     
     
         46 . The combination according to  claim 21 , wherein the pH of the aqueous medium is adjusted to a value of >6.5 prior to the addition of the surface-reacted natural calcium carbonate. 
     
     
         47 . The combination according to  claim 21 , wherein the pH of the aqueous medium is adjusted to a value of >7 prior to the addition of the surface-reacted natural calcium carbonate. 
     
     
         48 . The combination according to  claim 21 , wherein the one or more EDCs are selected from the group comprising endogenous hormone, 17β-estradiol (E2), estrone (E1), estriol (E3), testosterone, dihydro testosterone, a phyto hormone, a myco hormone, β-sitosterol, genistein, daidzein or zeraleon, a drug, 17α-ethinylestradiol (EE2), mestranol (ME), diethylstilbestrol (DES), an industrial chemical, 4-nonyl phenol (NP), 4-tert-octyl phenol (OP), bisphenol A (BPA), tributyltin (TBT), methylmercury, phthalates, PAK and PCB. 
     
     
         49 . The combination according to  claim 21 , wherein the activated carbon particles have a grain size of 0.1 μm to 5 mm. 
     
     
         50 . The combination according to  claim 21 , wherein the activated carbon particles have a grain size of 10 μm to 2 mm. 
     
     
         51 . The combination according to  claim 21 , wherein the activated carbon particles have a grain size of 0.1 mm to 0.5 mm 
     
     
         52 . The combination according to  claim 21 , wherein the activated carbon particles have a grain size of 0.3 mm. 
     
     
         53 . The combination according to  claim 21 , wherein the weight ratio of the surface-reacted natural calcium carbonate to the activated carbon is from 1:1 to 100:1. 
     
     
         54 . The combination according to  claim 21 , wherein the weight ratio of the surface-reacted natural calcium carbonate to the activated carbon is from 5:1 to 80:1. 
     
     
         55 . The combination according to  claim 21 , wherein the weight ratio of the surface-reacted natural calcium carbonate to the activated carbon is from 10:1 to 70:1. 
     
     
         56 . The combination according to  claim 21 , wherein the weight ratio of the surface-reacted natural calcium carbonate to the activated carbon is from 20:1 to 50:1. 
     
     
         57 . The combination according to  claim 21 , wherein the weight ratio of the surface-reacted natural calcium carbonate to the activated carbon is from 30:1 or 40:1.