Compositions and methods for reducing nitrogen volatilization of urea fertilizers

1. A nitrogen stabilizing composition comprising:

10% to 18% w/w N-(n-butyl) thiophosphoric triamide (NBPT);

a solvent comprising N-methyl-2-pyrrolidone (NMP), and two or more of propylene glycol, ethylene glycol, morpholine and glycerine;

1-5% w/w vegetable oil; and

1-5% w/w lecithin.

2. A composition according to claim 1 wherein the solvent comprises N-methyl-2-pyrrolidone (NMP), propylene glycol and ethylene glycol.

3. A composition according to claim 1 wherein the lecithin is sunflower lecithin.

4. A composition according to claim 1 further comprising 1% to 5% w/w of a surfactant.

5. A composition according to claim 4 wherein the surfactant is polysorbate 20.

6. A composition according to claim 1 wherein the pH of the composition is pH 6.5 to 7.5.

7. A composition according to claim 1 comprising 10% to 15% NBPT.

8. A composition according to claim 1 wherein the composition is provided in a form selected from the group consisting of a liquid, gel, and reconstitutable powder.

9. A composition according to claim 1 wherein the composition is coated on to a urea fertilizer to produce a coated urea fertilizer mixture.

10. A composition according to claim 9 wherein the urea fertilizer is granular.

11. A composition according to claim 9 wherein the composition is coated on to the urea fertilizer at approximately 1 L/1000 kg to 10 L/1000 kg.

12. A composition according to claim 11 wherein the composition is coated on to the urea fertilizer at a rate in a range of approximately 2 L/1000 kg to 3 L/1000 kg.

13. A composition according to claim 1 wherein the composition is combined with an aqueous urea fertilizer.

14. A composition according to claim 13 wherein the aqueous urea fertilizer is a urea-ammonium nitrate (UAN) solution (28-0-0).