An absorbent for the selective removal of hydrogen sulfide from a fluid stream comprising carbon dioxide and hydrogen sulfide, wherein the absorbent contains an aqueous solution, comprising: a) an amine or a mixture of amines of the general formula (I) wherein R.sup.1 is C.sub.1-C.sub.5-alkyl; R.sup.2 is C.sub.1-C.sub.5-alkyl; R.sup.3 is selected from hydrogen and C.sub.1-C.sub.5-alkyl; x is an integer from 2 to 10; and b) an ether or a mixture of ethers of the general formula (II): R.sup.4—[O—CH.sub.2—CH.sub.2].sub.y—OH; wherein R.sup.4 is C.sub.1-C.sub.5-alkyl; and y is an integer from 2 to 10; wherein R.sup.1 and R.sup.4 are identical; wherein the mass ratio of b) to a) is from 0.08 to 0.5. The absorbent is suitable for the selective removal of hydrogen sulfide from a fluid stream comprising carbon dioxide and hydrogen sulfide. The absorbent has a reduced tendency for phase separation at temperatures falling within the usual range of regeneration temperatures for the aqueous amine mixtures and is easily obtainable. ##STR00001##

Provided is an electrolyte salt comprising a quaternary ammonium cation indicated by formula (1) and a trimethylsilyl alkanesulfonate anion indicated by formula (2). ##STR00001##
(In the formula, R.sup.1-R.sup.4 each independently indicate a C1-4 alkyl group or an alkoxyalkyl group indicated by —(CH.sub.2).sub.n—OR. Any two among R.sup.1-R.sup.4 can mutually bond and form a ring together with a nitrogen atom to which same have bonded. The remaining two can mutually bond and form a spiro ring having a nitrogen atom as the spiro atom therefor. R indicates a methyl group or an ethyl group. n indicates 1 or 2 and m indicates 2 or 3.)

Provided is an electrolyte salt comprising a quaternary ammonium cation indicated by formula (1) and a trimethylsilyl alkanesulfonate anion indicated by formula (2). ##STR00001##
(In the formula, R.sup.1-R.sup.4 each independently indicate a C1-4 alkyl group or an alkoxyalkyl group indicated by —(CH.sub.2).sub.n—OR. Any two among R.sup.1-R.sup.4 can mutually bond and form a ring together with a nitrogen atom to which same have bonded. The remaining two can mutually bond and form a spiro ring having a nitrogen atom as the spiro atom therefor. R indicates a methyl group or an ethyl group. n indicates 1 or 2 and m indicates 2 or 3.)

An anionic-cationic-nonionic surfactant as substantially represented by the formula (I) exhibits significantly improved interfacial activity and stability as compared with the prior art. With the present anionic-cationic-nonionic surfactant, a flooding fluid composition for tertiary oil recovery with improved oil displacement efficiency and oil washing capability as compared with the prior art could be produced.

##STR00001##

In the formula (I), each group is as defined in the specification.

An anionic-cationic-nonionic surfactant as substantially represented by the formula (I) exhibits significantly improved interfacial activity and stability as compared with the prior art. With the present anionic-cationic-nonionic surfactant, a flooding fluid composition for tertiary oil recovery with improved oil displacement efficiency and oil washing capability as compared with the prior art could be produced.

##STR00001##

In the formula (I), each group is as defined in the specification.

Disclosed herein is a lipid having a net charge at physiological pH, and being covalently attached to a lipid moiety. The lipid moiety comprises a hydrocarbon structure having two or more linked hydrocarbon chains, optionally having cis or trans C═C, at least one of said chains being covalently attached to the head group optionally via the linker region. The hydrocarbon chains are bonded to one another at a branch point at an internal carbon of the chain attached to the linker region, which branch point comprises a functional group having an electronegative atom. The hydrocarbon chains each have between 1 and 40 carbon atoms, wherein the hydrocarbon structure in total comprises between 10 and 150 carbon atoms. Advantageously, the hydrocarbon structure may assume a generally flared shape for enhanced delivery of cargo molecules. Further provided are delivery vehicles comprising the lipids.

The present invention discloses a process for preparing a functionalized choline chloride ionic liquid as defined in formula (I), and thereof use in an electrochemical energy storage device, as an electrolyte solution or an additive for a lithium ion battery and a supercapacitor. The ionic liquid electrolyte material has better biocompatibility, flame retardance, high ionic conductivity, low viscosity, and wide electrochemical window. ##STR00001## wherein R.sup.1 is selected from the group consisting of: (CH.sub.2═CH—(CH.sub.2).sub.n)—, CN(CH.sub.2).sub.n—, or R.sup.2.sub.3Si—; R.sup.2 is selected from CH.sub.3—(CH.sub.2).sub.m—, n is an integer selected from 1 to 3, m is an integer selected from 0 to 2; or one of R.sup.2 is (CH.sub.3).sub.3Si—O—. Anion A in Formula I is selected from the group consisting of: Cl.sup.−, Br.sup.−, I.sup.−, BF.sub.4.sup.−, NO.sub.3.sup.−, SO.sub.4.sup.2−, CF.sub.3COO.sup.−, CF.sub.3SO.sub.3.sup.−, (CF.sub.3SO.sub.2).sub.2N.sup.−, PF.sub.6.sup.−, BF.sub.2C.sub.2O.sub.4.sup.−, or B(C.sub.2O.sub.4).sub.2.sup.−.

The present invention discloses a process for preparing a functionalized choline chloride ionic liquid as defined in formula (I), and thereof use in an electrochemical energy storage device, as an electrolyte solution or an additive for a lithium ion battery and a supercapacitor. The ionic liquid electrolyte material has better biocompatibility, flame retardance, high ionic conductivity, low viscosity, and wide electrochemical window. ##STR00001## wherein R.sup.1 is selected from the group consisting of: (CH.sub.2═CH—(CH.sub.2).sub.n)—, CN(CH.sub.2).sub.n—, or R.sup.2.sub.3Si—; R.sup.2 is selected from CH.sub.3—(CH.sub.2).sub.m—, n is an integer selected from 1 to 3, m is an integer selected from 0 to 2; or one of R.sup.2 is (CH.sub.3).sub.3Si—O—. Anion A in Formula I is selected from the group consisting of: Cl.sup.−, Br.sup.−, I.sup.−, BF.sub.4.sup.−, NO.sub.3.sup.−, SO.sub.4.sup.2−, CF.sub.3COO.sup.−, CF.sub.3SO.sub.3.sup.−, (CF.sub.3SO.sub.2).sub.2N.sup.−, PF.sub.6.sup.−, BF.sub.2C.sub.2O.sub.4.sup.−, or B(C.sub.2O.sub.4).sub.2.sup.−.

An acid gas absorbent includes at least one kind of secondary amine compound represented by formula (1): ##STR00001##
where R.sup.1 is a cyclopentyl group or a cyclohexyl group which may be substituted by a substituted or non-substituted alkyl group having 1 to 3 carbon atoms, R.sup.2 and R.sup.3 each indicate an alkylene group having 2 to 4 carbon atoms, and R.sup.2 and R.sup.3 may each be the same or different, and be a straight chain or have a side chain.

An acid gas absorbent includes at least one kind of secondary amine compound represented by formula (1): ##STR00001##
where R.sup.1 is a cyclopentyl group or a cyclohexyl group which may be substituted by a substituted or non-substituted alkyl group having 1 to 3 carbon atoms, R.sup.2 and R.sup.3 each indicate an alkylene group having 2 to 4 carbon atoms, and R.sup.2 and R.sup.3 may each be the same or different, and be a straight chain or have a side chain.