Carbon dioxide sorbents for air quality control
Carbon dioxide and VOC sorbents that include a porous support impregnated with an amine compound are provided. The sorbents include a gas-adsorbing material coated onto the porous support. The gas-adsorbing material includes a polyamine which is produced using a process that is free of formaldehyde as a reaction product and/or a reactant.
1. A sorbent comprising:
a porous support; and
a gas-adsorbing material coated onto the porous support, the gas-adsorbing material comprising one or more polyamines, wherein the one or more polyamines are produced from a reaction of an amine compound with a reactant, wherein the reactant comprises a carbonate ester compound or a ketone compound, and wherein the reaction is free of formaldehyde as a reaction product and/or a reactant.
2. The sorbent of claim 1 , wherein the amine compound comprises one or more of pentaethylenehexamine, diethanolamine, tetraethylenepentamine, triethylenetetramine, tetraethylenetetramine, bis(2-hydroxypropyl)amine, N,N′-bis(2-hydroxyethyl)ethylenediamine, monoethanolamine, diisopropanolamine, alkylamines, methylamine, linear polyethyleneimine, branched polyethyleneimine, dimethylamine, diethylamine, methyldiethanolamine, methylethanolamine, polyethylene polyamine, diethylenetriamine, N,N′-bis-(3-aminopropyl)ethylenediamine, or polyethylene.
3. The sorbent of claim 1 , wherein the amine compound comprises pentaethylenehexamine or N,N′-bis-(3-aminopropyl)ethylenediamine.
4. The sorbent of claim 1 , wherein the carbonate ester compound has a formula:
wherein R 1 and R 2 are independently selected from a group consisting of hydrogen, halogen, alkanoyl, alkyl, optionally substituted alkyl, cycloalkyl, optionally substituted cycloalkyl, alkenyl, optionally substituted alkenyl, cycloalkenyl, optionally substituted cycloalkenyl, alkynyl, optionally substituted alkynyl, hydroxy, aryl, optionally substituted aryl, aralkyl, (heterocyclo)alkyl, (heteroaryl)alkyl, (amino)alkyl, (alkylamino)alkyl, (dialkylamino)alkyl, (carboxamido)alkyl, (cyano)alkyl, alkoxyalkyl, and hydroxyalkyl.
5. The sorbent of claim 1 wherein the reactant comprises one or more of dimethyl carbonate or diethyl carbonate.
6. The sorbent of claim 1 , wherein the porous support comprises one or more of bentonite, attapulgite, kaolinite, montmorillonite, ball clay, fuller's earth, hectorite, palygorskite, saponite, sepiolite, halloysite, silica, calcium sulfate, zeolite, synthetic zeolite, alumina, titania, fumed silica, activated charcoal, or metal organic framework, and wherein the polyamine is present in an amount from 20% to 60% of a total weight of the sorbent.
7. The sorbent of claim 1 , wherein a surface area of the porous support is greater than 50 m 2 /g, wherein an average pore volume of the porous support is greater than 0.1 cc/g and less than 3.0 cc/g, and wherein the porous support is in a form of granules having a diameter ranging from about 0.25 mm to about 5 mm.
8. The sorbent of claim 1 , wherein the porous support comprises a silicon-based coating formed thereon.
9. The sorbent of claim 1 , wherein the sorbent is incorporated into an air filter unit of a system selected from a group consisting of: a CO 2 and/or volatile organic compound scrubbing system, an automobile ventilation system, an aircraft environmental control system, atmospheric air purification system, and a food storage system.
10. The sorbent of claim 1 , wherein the sorbent is incorporated into a paint composition or a polytetrafluoroethylene air filter sheet.
11. A sorbent comprising:
a porous support; and
a gas-adsorbing material coated onto the porous support, the gas-adsorbing material comprising one or more polyamines produced according to a reaction of pentaethylenehexamine and dimethyl carbonate, wherein the reaction is free of formaldehyde as a reaction product and/or a reactant.