Blown and stripped plant-based oils
View Patent ↗A method for producing a high viscosity, low volatiles blown stripped plant-based oil is provided. The method may include the steps of: (i) obtaining a plant-based oil; (ii) heating the oil to at least 90C; (iii) passing air through the heated oil to produce a blown oil having a viscosity of at least 200 cSt at 40C; (iv) stripping the blown oil from step (iii) to reduce an acid value of the blown oil to from 5 mg KOH/g to about 9 mg KOH/g; (v) adding a polyol to the stripped oil from (iv); and (vi) stripping the oil from step (v) to reduce the acid value of the oil to less than 5.0 mg KOH/g or less.
1. A method for producing a high viscosity, low volatiles blown stripped plant-based oil, the method comprising the steps of:
(a) obtaining a plant-based oil;
(b) heating the oil to at least 90° C.;
(c) passing air through the heated oil to produce a blown oil;
(d) stripping the blown oil from step (c) to reduce an acid value of the blown oil to from 5 mg KOH/g to about 9 mg KOH/g; and
(e) adding a polyol to the stripped oil from (d); and
(f) stripping the oil from step (e) to reduce the acid value of the oil to less than 5.0 mg KOH/g or less.
2. The method of claim 1 , wherein the oil resulting from step (f) exhibits a viscosity at 40° C. of at least 60 cSt.
3. The method of claim 1 wherein the oil resulting from step (f) exhibits a viscosity at 40° C. of at least 150 cSt.
4. The method of claim 1 , wherein the oil resulting from step (f) exhibits: a viscosity at 40° C. of at least 500 cSt; an acid value of 4 mg KOH/gram or less; a hydroxyl number of less than 50 mg KOH/gram; and a flash point of at least 293° C., in particular aspects, a flash point of at least 296° C.
5. The method of claim 1 , wherein the oil resulting from step (f) exhibits: a viscosity at 40° C. of at least 700 cSt; an acid value of 3.5 mg KOH/gram or less; a hydroxyl number of less than about 40 mg KOH/gram; and a flash point of at least 304° C.
6. The method of claim 1 , wherein the oil resulting from step (f) exhibits: a viscosity at 40° C. of at least 730 cSt; an acid value of 3.0 mg KOH/gram or less; a flash point of at least 315° C.; and a hydroxyl number of less than 30 mg KOH/mg.
7. The method of claim 5 , wherein the oil resulting from step (f) exhibits a flash point of at least 320° C.
8. The method of claim 5 , wherein the oil resulting from step (f) exhibits an acid value of 2.8 mg KOH/gram or less.
9. The method of claim 1 , wherein a catalyst comprising a peroxide or a metal selected from the groups consisting of Transition Elements and Group IV is added to the oil prior to or during step (c).
10. The method of claim 1 , wherein a catalyst is added to the oil prior to or during step (c), the catalyst comprising a metal selected from the group consisting of: tin, cobalt, iron, zirconium, titanium, and combinations thereof.
11. The method of claim 1 , wherein the polyol added comprises glycerin, and sufficient glycerin is added to obtain a molar ratio of added hydroxyl group to fatty acid groups present in the oil resulting from step (d) is from about 1:5 to less than about 1:1, in particular aspects, from about 2:5 to about 8:10.
12. The method of claim 1 , wherein the plant-based oil of step (a) is selected from the group consisting of: soybean oil, sunflower oil, safflower oil, canola oil, rapeseed oil, cottonseed oil, corn oil, corn stillage oil and mixtures thereof.
13. The method of claim 1 , wherein the plant-based oil of step (a) comprises corn stillage oil having an initial acid value from about 12 to about 34 mg KOH/gram.
14. The method of claim 1 , wherein the plant-based oil of step (a) comprises corn stillage oil having an initial acid value from about 16 to about 32 mg KOH/gram.