Non-extruded activated carbon honeycomb structures

Abstract

A non-extruded filter article, including: an activated carbon honeycomb substrate having a plurality of flow-through channels and porous walls, and the activated carbon substrate comprises a carbon in from 90 to 99.9 wt. % of the article, and the porous walls have a percentage porosity of from 40% to 65%. Also disclosed is a non-extrusion method of making the article and a method of using the article.

What is claimed is: 
     
         1 . A method, comprising:
 contacting a shaped cellulosic substrate and an activating agent to form a treated substrate;   heating the treated substrate to form a carbon substrate; and   removing a portion of the activating agent from the carbon substrate to form an activated carbon honeycomb filter article having a plurality of flow-through channels, a carbon content in a range of 90 wt. % to 99.9 wt. % of the filter article, and porous walls having a porosity in a range of 40% to 65%.   
     
     
         2 . The method of  claim 1 , wherein the shaped cellulosic substrate has porous walls and a plurality of flow-through channels. 
     
     
         3 . The method of  claim 1 , wherein heating the treated substrate is conducted at a temperature in a range of 500° C. to 850° C. in an inert atmosphere. 
     
     
         4 . The method of  claim 1 , wherein the activated carbon honeycomb filter article is a non-extruded filter article. 
     
     
         5 . The method of  claim 1 , further comprising: contacting an outer surface of the shaped cellulosic substrate with a binder prior to heating the treated substrate. 
     
     
         6 . The method of  claim 1 , further comprising: contacting the shaped cellulosic substrate with a carbon source material prior to heating the treated substrate. 
     
     
         7 . The method of  claim 6 , wherein the carbon source material is at least one of: a phenolic resin, a cellulose powder, an activated carbon, a charcoal, a coal-based material, an organic char, or combinations thereof. 
     
     
         8 . The method of  claim 1 , further comprising: contacting the treated substrate with a zero-valent iron nanoparticle, a gamma-alumina, a ceria oxide, or combinations thereof. 
     
     
         9 . The method of  claim 1 , wherein removing the portion of the activating agent removes from 90 wt. % to 99.9 wt. % of the activating agent, and the cellulosic substrate is from 90 to 99.9 vol % paper. 
     
     
         10 . The method of  claim 1 , wherein removing the portion of the activating agent is accomplished by washing the carbon substrate with an acid. 
     
     
         11 . The method of  claim 1 , wherein the activating agent is selected from at least one of an alkali metal, a transition metal salt, or combinations thereof. 
     
     
         12 . The method of  claim 1 , wherein the activating agent is selected from at least one of KOH, NaOH, K 2 CO 3 , ZnCl 2 , and combinations thereof. 
     
     
         13 . The method of  claim 6 , wherein the carbon source material is an organic char selected from at least one of: a wheat flour, a coconut shell, a pecan flour, a cherry pit flour, a rice hull, sawdust, or combinations thereof. 
     
     
         14 . The method of  claim 1 , wherein heating the treated substrate is conducted at a time in a range of 2 to 10 hours. 
     
     
         15 . The method of  claim 1 , further comprising:
 coating a thermoset polymer on an exterior of the shaped cellulosic substrate prior to contacting with a carbon source material or the activating agent, the thermoset polymer being at least one of: a phenolic resin, an aromatic polyamide, a urea, a polyimide, a melamine resin, an epoxide, a carboxymethyl cellulose, or combinations thereof.   
     
     
         16 . A method comprising:
 contacting an activated carbon honeycomb filter article with a fluid having a contaminant, wherein the carbon honeycomb filter article has a carbon content in a range of 90 wt. % to 99.9 wt. % of the filter article, and porous walls having a porosity in a range of 40% to 65%.   
     
     
         17 . The method of  claim 16 , wherein the fluid is a liquid, a gas, a suspension, a solution, or combinations thereof; and the contaminant is selected from the group consisting of a heavy metal, a volatile organic compound, and combinations thereof. 
     
     
         18 . The method of  claim 17 , wherein the heavy metal is at least one of: arsenic, cadmium, chromium, copper, selenium, lead, mercury, or combinations thereof, and the volatile organic compound is at least one of: benzene, formaldehyde, methylene chloride, perchloroethylene, or combinations thereof. 
     
     
         19 . The method of  claim 16 , wherein the carbon honeycomb filter article is a non-extruded filter article.