Activated carbon-containing sorbent
An activated carbon-containing sorbent is capable of selectively removing one or more selected gaseous components from a gas. The activated carbon-containing sorbent can be incorporated in a smoking article to remove one or more selected components from mainstream smoke. The activated carbon-containing sorbent can be a composite including one or more molecular sieve materials. Methods of making the activated carbon-containing sorbent, cigarette filters and smoking articles including the activated carbon-containing sorbent, as well as methods for smoking a cigarette comprising the activated carbon-containing sorbent, are provided.
1. A method of making an activated carbon-containing sorbent, comprising:
curing a first resin;
comminuting the cured first resin into first cured resin particles;
mixing the first cured resin particles with uncured second resin particles to produce a mixture wherein the mixing further comprises mixing the first resin particles and the uncured second resin with at least one molecular sieve material to produce the mixture;
curing the second resin particles to form a cured mixture;
carbonizing the cured mixture to produce a carbonized body; and
activating the carbonized body to produce an activated carbon-containing sorbent.
2. The method of claim 1 , wherein the first resin and the second resin are a phenolic resin.
3. The method of claim 1 , wherein the first resin and the second resin are solid particles and have the same composition.
4. The method of claim 1 , wherein the second resin is in particle form, and the first resin particles and the second resin particles have approximately the same average particle size and/or particle size distribution.
5. The method of claim 1 , wherein the mixture has a weight ratio of the first resin to the second resin of about 80:20 to about 60:40.
6. The method of claim 1 , wherein the cured first resin is a solid mass comminuted into the first cured resin particles by mechanical impaction.
7. The method of claim 1 , wherein the first resin is cured at a first temperature and the second resin particles are cured at a second temperature lower than the first temperature.
8. The method of claim 1 , further comprising shaping the mixture into a selected shape prior to curing the mixture, wherein the cured mixture has substantially the selected shape.
9. The method of claim 1 , wherein the activated carbon-containing sorbent has an average pore size less than 15 Å.
10. The method of claim 1 , wherein the activated carbon-containing sorbent is a cylindrical monolith.
11. The method of claim 1 , wherein the activated carbon-containing sorbent has a BET surface area of from about 500 m 2 /g to about 1,500 m 2 /g.
12. The method of claim 1 , wherein the activated carbon-containing sorbent consists essentially of activated carbon and the at least one molecular sieve material.
13. The method of claim 1 , wherein:
the mixing further comprises mixing the first resin particles and the uncured second resin with at least one pore-forming substance to produce the mixture; and
the activating further comprises removing substantially all of the pore-forming substance from the carbonized body by evaporation thereby producing pores in the activated carbon-containing sorbent.
14. The method of claim 13 , wherein the at least one pore-forming substance is poly(vinylalcohol) and/or polypropylene.
15. The method of claim 13 , wherein the at least one molecular sieve material includes a zeolite, and the at least one pore-forming substance is poly(vinylalcohol) and/or polypropylene.
16. A method of making a cigarette filter, comprising:
making at least one activated carbon-containing monolithic sorbent by the method according to claim 13 ; and
incorporating in a filter the at least one activated carbon-containing monolithic sorbent.