Separations with ionic liquid solvents

Patent metadata

Field	Value
Publication number	US-10227274-B2
Application number	US-201514597415-A
Country	US
Kind code	B2
Filing date	Jan 15, 2015
Priority date	Jul 23, 2013
Publication date	Mar 12, 2019
Grant date	Mar 12, 2019

Abstract

Disclosed are systems and methods which provide a process stream comprising a gaseous component, capture the gaseous component from the process stream by an ionic liquid solvent of a separator, and recover a captured gaseous component from the ionic liquid solvent in a regenerator. A second gaseous component from the process stream may be captured by the ionic liquid solvent of the separator, and the second gaseous component may be recovered from the ionic liquid solvent in the regenerator. Alternatively, the second gaseous component from the process stream may be uncaptured by the ionic liquid solvent, and the uncaptured second gaseous component may be recovered from a membrane unit.

First claim

We claim:

1. A method comprising:
providing a process stream comprising an olefin;
capturing at least a portion of the olefin from the process stream by an ionic liquid solvent; and
recovering at least a portion of a captured olefin from the ionic liquid solvent,
wherein the ionic liquid solvent has a total solubility of the olefin greater than the total solubility of the olefin in [emim][Tf 2 N]—Ag,
wherein the ionic liquid solvent comprises butylmethylimidazolium thiocyanate ([bmim][SCN]), N-butyl-4-methylpyridinium thiocyanate ([N-b-4-mpy][SCN]), ethoxyethylmethylimidazolium tetrafluoroborate ([etO-emim][BF 4 ]), ethoxyethylmethylimidazolium hexafluorophosphate ([etO-emim] [PF 6 ]), ethoxyethylmethylimidazolium trifluoroacetate ([etO-emim][TFA]), ethoxyethylmethylimidazolium trifluoromethanesulfonate ([etO-emim][TfO]), ethoxyethylmethylimidazolium nitrate ([etO-emim][NO 3 ]), ethoxydimethylimidazolium methanesulfonate ([etO-mmim][CH 3 SO 3 ]), ethoxydimethylimidazolium trifluoroacetate ([etO-mmim][TFA]), methoxyethylmethylimidazolium tetrafluoroborate ([meO-emim][BF 4 ]), methoxyethylmethylimidazolium hexafluorophosphate ([meO-emim] [PF 6 ]), methoxyethylmethylimidazolium trifluoroacetate ([meO-emim] [TFA]), methoxyethylmethylimidazolium trifluoromethanesulfonate ([meO-emim][TfO]), methoxyethylmethylimidazolium nitrate ([meO-emim][NO 3 ]), methoxypropylmethylimidazolium tetrafluoroborate ([meO-prmim][BF 4 ]), methoxypropylmethylimidazolium hexafluorophosphate ([meO-prmim][PF 6 ]), methoxypropylmethylimidazolium trifluoroacetate ([meO-prmim][TFA]), methoxypropylmethylimidazolium trifluoromethanesulfonate ([meO-prmim][TfO]), hydroxylethylmethylimidazolium methanesulfonate ([OH-emim][CH 3 SO 3 ]), hydroxyloctylmethylimidazolium tetrafluoroborate ([OH-omim][BF 4 ]), hydroxyloctylmethylimidazolium hexafluorophosphate ([OH-omim][PF 6 ]), hydroxyloctylmethylimidazolium nitrate ([OH-omim][NO 3 ]), hydroxylpropylmethylimidazolium methanesulfonate ([OH-prmim][CH 3 SO 3 ]), hydroxypropylpyridinium methanesulfonate ([OH-prpy][CH 3 SO 3 ]), butylethyldimethylammonium tetrafluoroborate ([bemm-N][BF 4 ]), butylethyldimethylammonium hexafluorophosphate ([bemm-N][PF 6 ]), butylethyldimethylammonium trifluoroacetate ([bemm-N][TFA]), butylethyldimethylammonium trifluoromethanesulfonate ([bemm-N][TfO]), butyltrimethylammonium trifluoroacetate ([bmmm-N][TFA]), butyltrimethylammonium trifluoromethanesulfonate ([bmmm-N][TfO]), butyltrimethylammonium nitrate ([bmmm-N][NO 3 ]), N,N,N-trimethylethanolammonium methanesulfonate ([choline][CH 3 SO 3 ]), N,N,N-trimethylethanolammonium nitrate ([choline][NO 3 ]), ethylammonium hexafluorophosphate ([e-N][PF 6 ]), tetraethylammonium trifluoromethanesulfonate ([eeee-N][TfO]), butyldimethylethanolammonium trifluoroacetate ([OHe-bmm-N][TFA]), butyldimethylethanolammonium trifluoromethanesulfonate ([OHe-bmm-N][TfO]), butyldimethylethanolammonium nitrate ([OHe-bmm-N][NO 3 ]), ethyldimethylethanolammonium nitrate ([OHe-emm-N][TFA]), or combinations thereof.

2. A method comprising:
providing a polymerization process stream comprising ethylene and isobutane;
capturing at least a portion of the ethylene from the polymerization process stream by an ionic liquid solvent; and
recovering at least a portion of a captured ethylene from the ionic liquid solvent,
wherein the ionic liquid solvent has a total solubility of an olefin greater than the total solubility of the olefin in [emim][Tf 2 N]—Ag,
wherein the ionic liquid solvent comprises a cation and an anion;
wherein the cation comprises a butylethylimidazoliumn cation, butyldimethylimidazolium cation, decaethylimidazolium cation, a decamethylimidazolium cation, a diethylimidazolium cation, dimethylimidazolium cation, an ethyl-2,4-dimethylimidazolium cation, an ethyldimethylimidazolium cation, an ethylimidazolium cation, an ethylmethylimidazolium cation, an ethylpropylimidazolium cation, an ethoxyethylmethylimidazolium cation, an ethoxydimethylimidazolium cation, a hexadecylmethylimidazolium cation, a heptylmethylimidazolium cation, a hexylethylimidazolium cation, a hexylmethylimidazolium cation, a hexyldimethylimidazolium cation, a methoxyethylmethylimidazolium cation, a methoxypropylmethylimidazolium cation, a methylimidazolium cation, dimethylimidazolium cation, a methylnonylimidazolium cation, an octadecylmethylimidazolium cation, a hydroxylethylmethylimidazolium cation, a hydroxyloctylmethylimidazolium cation, a hydroxylpropylmethylimidazolium cation, an octylmethylimidazolium cation, an octyldimethylimidazolium cation, a phenylethylmethylimidazolium cation, a phenylmethylimidazolium cation, a phenyldimethylimidazolium cation, a pentylmethylimidazolium cation, a propylmethylimidazolium cation, a 1-butyl-2-methylpyridinium cation, 1-butyl-3-methylpyridinium cation, a butylmethylpyridinium cation, a 1-butyl-4-dimethylacetylpyridinium cation, a 1-butyl-4-methylpyridinium cation, a 1-ethyl-2-methylpyridinium cation, a 1-ethyl-3-methylpyridinium cation, a 1-ethyl-4-dimethylacetylpyridinium cation, a 1-ethyl-4-methylpyridinium cation, a 1-hexyl-4dimethylacetylpyridinium cation, a 1-hexyl-4-methylpyridinium cation, a 1-octyl-3-methylpyridinium cation, a 1-octyl-4-methylpyridinium cation, a 1-propyl-3-methylpyridinium cation, a 1-propyl-4-methylpyridinium cation, a butylpyridinium cation, an ethylpyridinium cation, a heptylpyridinium cation, a hexylpyridinium cation, a hydroxypropylpyridinium cation, an octylpyridinium cation, a pentylpyridinium cation, a propylpyridinium cation, a butylmethylpyrrolidinium cation, a butylpyrrolidinium cation, a hexylmethylpyrrolidinium cation, a hexylpyrrolidinium cation, an octylmethylpyrrolidinium cation, an octylpyrrolidinium cation, a propylmethylpyrrolidinium cation, a butylammonium cation, a tributylammonium cation, a tetrabutylammonium cation, a butylethyldimethylammonium cation, a butyltrimethylammonium cation, a N,N,N-trimethylethanolammonium cation, an ethylammonium cation, a diethylammonium cation, a tetraethylammonium cation, a tetraheptylammonium cation, a tetrahexylammonium cation, a methylammonium cation, a dimethylammonium cation, a tetramethylammonium cation, an ammonium cation, a butyldimethylethanolammonium cation, a dimethylethanolammonium cation, an ethanolammonium cation, an ethyldimethylethanolammonium cation, a tetrapentylammonium cation, a tetrapropylammonium cation, a tetrabutylphosphonium cation, a tributyloctylphosphonium cation, or combinations thereof;
wherein the anion comprises a bis(trifluoromethanesulfonyl)amide anion, a thiocyanate anion, or combinations thereof.

3. The method of claim 1 , wherein the total solubility of the olefin in the ionic liquid solvent is about 0.01 to about 100 mol/L.

4. The method claim 1 , wherein a total selectivity of the ionic liquid solvent to the olefin is from about 8 to about 300.

5. The method of claim 1 , wherein the ionic liquid solvent comprises a Ag(I) salt, a Cu(I) salt, or combinations thereof.

6. The method of claim 5 , wherein a concentration of silver, copper, or both, in the ionic liquid solvent is from about 0.1 N to about 5 N.

7. The method of claim 6 , wherein the concentration of silver, copper, or both, in the ionic liquid solvent is from about 0.45 N to about 1.8 N.

8. The method of claim 1 , wherein said capturing is performed at a liquid-to-gas mass flow ratio from about 1 to about 350.

9. The method of claim 1 , further comprising:
flowing the ionic liquid solvent at a mass flow rate from about 1,000 pounds per hour to about 300,000 pounds per hour.

10. The method of claim 1 , wherein the process stream further comprises an alkane.

11. The method of claim 10 , wherein a total solubility of the alkane in the ionic liquid solv

Assignees

• Chevron Phillips Chemical Co Lp
• Chevron Usa Inc

Inventors

• Ji Lei
• Chang Ai-Fu
• Driver Michael Sean
• Timken Hye-Kyung Cho

Classifications

• B01D2257/504

  Carbon dioxide · CPC title

• Y02P20/51

  Cross-Sectional Technologies · mapped topic

• B01D53/1487

  Removing organic compounds · CPC title

• C07C7/11 Primary

  by absorption, i.e. purification or separation of gaseous hydrocarbons with the aid of liquids · CPC title

• B01D2257/304

  Hydrogen sulfide · CPC title