High-purity composite materials, methods of making high-purity composite materials, and methods of using high-purity composite materials

Abstract

A composite filter aid may include acid-washed diatomaceous earth and a low extractable metal mineral. A method for making a composite material may include blending an acid-washed diatomaceous earth and a low extractable metal mineral, adding a binder to the blended diatomaceous earth and low extractable metal mineral, and forming the composite material from the acid-washed diatomaceous earth, the low extractable metal mineral, and the binder. A method for filtering a liquid may include providing a liquid for filtering and filtering the liquid through a composite filter aid that includes an acid-washed diatomaceous earth and a low extractable metal mineral.

1 - 36 . (canceled) 
     
     
         37 . A method for making a composite material, the method comprising:
 washing a diatomaceous earth with at least one acid, followed by rinsing the acid washed diatomaceous earth with water;   blending the acid-washed diatomaceous earth and a low extractable metal mineral comprising perlite;   adding a binder to the blended acid washed diatomaceous earth and low extractable metal mineral; and   forming the composite material from the acid-washed diatomaceous earth, the low extractable metal mineral, and the binder.   
     
     
         38 . The method of  claim 37 , further comprising dispersing the binder in water. 
     
     
         39 . The method of  claim 37 , further comprising dispersing the binder in water before adding the binder to the blended acid-washed diatomaceous earth and low extractable metal mineral. 
     
     
         40 . The method of  claim 37 , further comprising mixing the binder and the blended acid-washed diatomaceous earth and low extractable metal mineral. 
     
     
         41 . The method of  claim 40 , further comprising classifying the mixed binder and blended acid-washed diatomaceous earth and low extractable metal mineral. 
     
     
         42 . The method of  claim 40 , further comprising drying the mixed binder and blended acid-washed diatomaceous earth and low extractable metal mineral. 
     
     
         43 . The method of  claim 42 , wherein the drying comprises heating the mixed binder and blended acid-washed diatomaceous earth and low extractable metal mineral to a temperature in a range from 100° C. to 200° C. 
     
     
         44 . The method of  claim 43 , further comprising, after drying the mixture, classifying the mixture. 
     
     
         45 . The method of  claim 37 , wherein the composite material has a permeability in a range from 0.5 to 20 darcys. 
     
     
         46 . The method of  claim 37 , further comprising, prior to blending the acid-washed diatomaceous earth and low extractable metal mineral, calcining the diatomaceous earth. 
     
     
         47 . The method of  claim 37 , wherein the composite material has a d50 in a range from 30 to 70 microns. 
     
     
         48 . The method of  claim 37 , wherein the composite material has a BET surface area in a range from 5 m 2 /g to about 50 m 2 /g. 
     
     
         49 . The method of  claim 37 , wherein the porosity of the composite material in a range from 3 to 7 mL/g. 
     
     
         50 - 54 . (canceled) 
     
     
         55 . The method of  claim 37 , wherein the at least one acid is selected from sulfuric acid (H 2 SO 4 ), hydrochloric acid (HCl), phosphoric acid (H 3 PO 4 ), nitric acid (HNO 3 ), citric acid (C 6 H 8 O 7 ) and acetic acid (CH 3 COOH).