Controlled Release Fertilizer Composition

• US 20100011825A1
• Filed: 07/16/2008
• Published: 01/21/2010
• Est. Priority Date: 07/16/2008
• Status: Active Grant

• Current Assignee: KOCH Agronomic Services LLC (KOCH Industries Incorporated)
• Original Assignee: Agrium Incorporated (Nutrien Ltd.)
• Inventors: OGLE, Jeffrey Michael, Sims, Johnny Duran
• Granted Patent: US 7,771,505 B2
• Time in Patent Office: Days
• US Class Current: 71/30
• CPC Class Codes: C05C 9/005 Post-treatment
• CPC Class Codes: C05G 5/36 layered or coated with sulfur
• CPC Class Codes: C05G 5/37 layered or coated with a polymer
• CPC Class Codes: C05G 5/38 layered or coated with wax or resins

Abstract

A controlled release fertilizer composition and methods to produce the controlled release fertilizer composition are described. The controlled release fertilizer composition comprises a water soluble fertilizer core that is coated with a polymeric layer, intermediate layer, and a sulfur layer. If desired, the sulfur layer can be coated with an outer water-insoluble layer.

Claims

1. A controlled release fertilizer composition comprising a core of a water-soluble plant nutrient compound, the core coated with, in series proceeding from the core outward, a polymer layer, an intermediate layer, and a layer of elemental sulfur.

2. The control release fertilizer of claim 1, wherein the water soluble plant nutrient is urea.

3. The control release fertilizer of claim 1, wherein the polymer layer is a thermoset polymer layer.

4. The control release fertilizer of claim 1 comprising an outer, water-insoluble layer.

5. The control release fertilizer of claim 1, wherein the intermediate layer comprises a component selected from the group consisting of a wax, an oil, a lubricant, a surfactant, or a combination thereof.

6. The control release fertilizer of claim 4, wherein the intermediate layer and the outer, water-insoluble layer are the same or different, and comprise a component selected from the group consisting of a wax, an oil, a lubricant, a surfactant, or a combination thereof.

7. The composition of claim 1, wherein the water soluble plant nutrient compound is from about 37% N to about 44% N on a weight basis, the polymer layer is from about 1.2% to 3.0% on a weight basis, the intermediate layer is from about 0.1% to about 0.8% on a weight basis, the layer of elemental sulfur is from about 1.7% to 15% on a weight basis and the outer, water-insoluble layer is from about 0.1% to about 0.8% on a weight basis.

15. The process of claim 6, wherein the water soluble plant nutrient compound is from about 37% N to about 44% N on a weight basis, the polymer is from about 1.2% to 3.0% on a weight basis, the intermediate layer is from about 0.1% to about 0.8% on a weight basis, the layer of sulfur is from about 1.7% to 15.0% on a weight basis and the outer, water-insoluble layer is from about 0.1% to about 0.8% on a weight basis.

8. A method of producing a controlled release fertilizer composition comprising,

i) coating a plant nutrient compound with two or more than two precursor compounds reactive to form a polymer,

ii) applying a intermediate layer onto the polymer, and

iii) spraying molten sulfur onto the intermediate layer to form a sulfur layer.

9. The process of claim 8, wherein the plant nutrient compound is urea.

10. The process of claim 8, wherein after the step of spraying molten sulfur, an outer, water-insoluble layer is applied over the sulfur layer.

11. The method of claim 8, wherein the polymer is a thermoset polymer, and the step of coating the plant nutrient compound with two or more than two precursor compounds reactive to form a polymer is at a temperature sufficient to thermoset the polymer.

12. The method of claim 8, wherein the two or more than two precursor compounds are a polyisocyanate and a polyol.

13. The process of claim 8, wherein the intermediate layer is selected from the group consisting of a wax, an oil, a lubricant, a surfactant, or a combination thereof.

14. The process of claim 10, wherein the water insoluble layer is selected from the group consisting of a wax, an oil, a lubricant, a surfactant, or a combination thereof.