Crosslinking composition for hydrocarbon gels
A crosslinking composition for hydrocarbon gels containing phosphate ester gelling agents comprising a modified imidazoline or pyrimidine including an alkyl group (or unsaturated carbon chain) or of 10 to 22 carbon atoms, a polyamine, and ferric sulfate. The method of making the crosslinking agent features adding the polyamine after reaction of the other ingredients; unique gels formed with the crosslinking agent are particularly effective for LNG at very cold temperatures.
1. A crosslinking composition for making gels in hydrocarbons comprising the reaction product of, in parts by weight (“p/w”):
(a) 13-17 p/w of a compound of the formula R 3 —O R 4 —O 1-2 H where R 3 is a linear or branched alkyl group of 3-6 carbon atoms and each R 4 is independently a linear or branched alkyl group of 2-6 carbon atoms, or a mixture of such compounds,
(b) 8.5-10.5 p/w of an imidazoline or pyrimidine of the formula
where R 1 is an amino alkyl group containing 2 to 6 carbon atoms and R 2 is an alkyl group (or unsaturated carbon chain) or of 10 to 22 carbon atoms.
(c) 3.6-4.5 p/w of an amide or mixture of amides made by reacting a vegetable oil and a polyamine of the formula
where w is a number from 0-15, x is a number from 2-8, y is 0 or 1, z is a number from 0 to 8, and m and n are independently selected numbers from 0 to 15,
(d) 1.6-2.0 p/w of a vegetable oil diethanolamide,
(e) 0-5.0 p/w sodium dodecene sulfonate in 40-60% water,
(f) 0-5.0 p/w glycerin,
(g) 54-67 p/w ferric sulfate, 40-80% in water, and
(h) 0.1-4 p/w polyamine of the formula
where w is a number from 0-15, x is a number from 2-8, y is 0 or 1, z is a number from 0 to 8, and m and n are independently selected numbers from 0 to 15, said crosslinking composition being effective to form a gel in with a phosphate ester gelling agent in LNG at a temperature of from −20° C. to −28° C.
2. Crosslinking composition of claim 1 wherein said polyamine (h) comprises dimethylaminopropyl amine.
3. Crosslinking composition of claim 1 wherein said imidazoline (b) comprises an imidazoline made by reacting diethylene triamine with tall oil.
4. Crosslinking composition of claim 1 wherein said amide (c) comprises an amide made by reacting soybean oil with dimethyl aminopropylamine.
5. Crosslinking composition of claim 1 wherein said diethanolamide (d) comprises a diethanolamide made by reacting coconut oil with diethanolamine.
6. Crosslinking composition of claim 1 wherein R 1 in said imidazoline (b) contains two amine groups.
7. Crosslinking composition of claim 1 wherein said polyamine (h) comprises didecylamionohexylamine.
8. Crosslinking composition of claim 1 wherein said compound (a) comprises ethylene glycol 2-butane ethanol.
9. Method of making a crosslinking composition for hydrocarbon gels comprising (a) mixing together (i) 13-17 parts by weight one or more compounds of the formula R 3 —O R 4 —O 1-2 H where R 3 is a linear or branched alkyl group of 3-6 carbon atoms and each R 4 is independently a linear or branched alkyl group of 2-6 carbon atoms, or a mixture of such compounds,
(ii) 8.5-10 parts by weight of an imidazoline or pyrimidine of the formula
where R 1 is an amino alkyl group containing 2 to 6 carbon atoms and R 2 is an alkyl group (or unsaturated carbon chain) or of 10 to 22 carbon atoms, or a pyrimidine having similar substituent groups, (iii) 3.6-4.5 parts by weight of an amide or mixture of amides made by reacting a vegetable oil and a polyamine of the formula
where w is a number from 0-15, x is a number from 2-8, y is 0 or 1, z is a number from 0 to 8, and m and n are independently selected numbers from 0 to 15,
(iv) 1.6-2.0 parts by weight of a vegetable oil diethanolamide, (v) 4.0-5.0 parts by weight sodium dodecene sulfonate in 40-60% water, and (vi) 5.0-5.0 parts by weight glycerin, thereby causing an exotherm, (b) further mixing into said mixture 0.1-4 parts by weight of a polyamine of the formula
where w, x, y, z, m, and n are as indicated above, (c) mixing into said mixture 54-67 parts by weight ferric sulfate (40-80% in water), and (d) cooling said mixture throughout said mixing in steps (a), (b), and (c) to control said exotherm.
10. Method of claim 9 wherein said polyamine in step (b) comprises dimethylaminopropyl amine.
11. Method of claim 9 wherein said imidazoline in step (a) (ii) comprises an imidazoline made by reacting diethylene triamine with tall oil.
12. Method of claim 9 wherein said amide (a) (iii) comprises an amide made by reacting soybean oil with dimethyl aminopropylamine.
13. Method of claim 9 wherein said diethanolamide in step (a) (iv) comprises a diethanolamide made by reacting coconut oil with diethanolamine.
14. Method of claim 9 wherein said compound (a) (i) comprises ethylene glycol 2-butane ethanol.