Metal Contaminant Removal Compositions and Methods for Making and Using The Same

Abstract

Metal sorbent compositions for removing a metal contaminant from a fluid, such as removal of mercury from a coal-fired flue gas stream, and methods for making and using the same are provided. The subject metal sorbent compositions comprise an effective amount of an aqueous dispersion of microfine elemental sulfur particles on an adsorbent substrate, and optionally, a metal capture enhancing agent such as a halogen source and/or an oxidizing agent in an amount providing a metal capture enhancing effect on the metal sorbent composition. The subject metal sorbent compositions are prepared by drying an aqueous dispersion of microfine elemental sulfur particles on an adsorbent substrate, such as on a substrate of microfine particles of a refractory material and the like. Also provided are kits for use in preparing the subject compositions, and compositions produced by the methods. The subject compositions, kits and systems find use in a variety of different applications.

1 - 19 . (canceled) 
     
     
         20 . A method of removing a metal contaminant from a fluid, the method comprising:
 (a) contacting the fluid with a metal capturing effective amount of a metal sorbent composition, the metal sorbent composition comprising an aqueous dispersion of microfine elemental sulfur particles supported on an adsorbent substrate, and optionally, a metal capture enhancing agent in an amount having a metal capture enhancing effect on the metal sorbent composition;   (b) forming an adduct comprising the metal sorbent composition and one or more metal contaminants of the fluid; and   (c) removing the adduct.   
     
     
         21 . The method according to  claim 20 , wherein the metal contaminant is mercury. 
     
     
         22 . The method according to  claim 20 , wherein the fluid is coal-fired flue gas. 
     
     
         23 . The method according to  claim 22 , wherein the adduct is comprised as a component of treated fly ash. 
     
     
         24 . The method according to  claim 23 , wherein leachate from the adduct contains less than about 0.2 parts per million (ppm) mercury as measured by the Toxicity Characteristic Leaching Procedure (TCLP). 
     
     
         25 . (canceled)