Sulphur-containing fertilizers and process for the preparation thereof

• US 8,702,834 B2
• Filed: 01/29/2010
• Issued: 04/22/2014
• Est. Priority Date: 01/29/2009
• Status: Active Grant

• Current Assignee: Shell USA Incorporated (Shell Plc)
• Original Assignee: Shell Oil Company (Shell Plc)
• Inventors: Antens, Jany Birgitta Maria, Garcia Martinez, Rafael Alberto, Lambert, Reginald, Reynhout, Marinus Johannes, Verbist, Guy Lode Magda Maria, Woodruffe, John, O'Brien, Jason Trevor
• Primary Examiner(s): LANGEL, WAYNE A
• Application Number:
  US13/146,451
• Publication Number:
  US 20110302975A1
• Time in Patent Office: 1,544 Days
• Field of Search: 71 32- 53, 71/640.3, 516198-204
• US Class Current: 71/33
• CPC Class Codes: C05B 1/00 Superphosphates, i.e. fertilisers produced by reacting rock or bone phosphates with sulfuric or phosphoric acid in such amounts and concentrations as to yield solid products directly
• CPC Class Codes: C05B 7/00 Fertilisers based essentially on alkali or ammonium orthophosphates C05B11/00 takes precedence
• CPC Class Codes: C05D 9/00 Other inorganic fertilisers
• CPC Class Codes: C05G 3/50 Surfactants; Emulsifiers
• CPC Class Codes: C05G 5/12 Granules or flakes

Abstract

According to the present invention, there is provided a process for the manufacture of sulphur-containing fertilizer compositions, said process comprising the steps of: a) providing a slurry of at least one phosphate-based fertilizer material selected from the group consisting of ammonium phosphates, ammonium phosphate based nitrogen-phosphorus-potassium (NPK) compounds, super phosphates and partially acidulated phosphate rocks; b} bringing said slurry into contact with at least one surfactant and elemental sulphur; and c) introducing the mixture obtained in step b) into a granulator unit in order to obtain granules of the fertilizer composition, wherein the elemental sulphur is present in an amount in the range of form 1 to 25 wt. %, based on the total weight of the fertilizer composition The present invention also provides a fertilizer composition.

Claims

1. A process for the manufacture of sulphur-containing fertilizer compositions, said process comprising the steps of:

a) providing a slurry of at least one phosphate-based fertilizer material selected from the group consisting of ammonium phosphates, ammonium phosphate based nitrogen-phosphorus-potassium (NPK) compounds, super phosphates and partially acidulated phosphate rocks;

b) bringing said slurry into contact with at least one cationic or amphoteric surfactant and a liquid phase of elemental sulphur; and

c) introducing the mixture obtained in step b) into a granulator unit in order to obtain granules of the fertilizer composition,

wherein the elemental sulphur is present in an amount in the range of from 1 to 25 wt. % and the at least one cationic or amphoteric surfactant is present in an amount in the range of from 0.001 to 3 wt. %, based on the total weight of the fertilizer composition.

2. A process as claimed in claim 1, wherein the liquid phase of elemental sulphur comprises molten sulphur.

3. A process as claimed in claim 1, wherein the at least one cationic or amphoteric surfactant comprises an ethylene or propylene oxide adduct of an aliphatic amine, said aliphatic amine containing 12 to 20 carbon atoms.

4. A process as claimed in claim 1, wherein the at least one cationic or amphoteric surfactant is present in an amount in the range of from 0.001 wt. % to 0.05 wt. % with respect to the weight of the overall fertilizer composition.

5. A process as claimed in claim 1, wherein the at least one cationic or amphoteric surfactant is a nitrogen-containing cationic surfactant or a nitrogen-containing amphoteric surfactant.

6. A fertilizer composition comprising:

a) elemental sulphur in an amount in the range of from 1 to 25 wt. %, based on the total weight of the fertilizer composition;

b) at least one phosphate-based fertilizer material selected from the group consisting of ammonium phosphates, ammonium phosphate based nitrogen-phosphorus-potassium (NPK) compounds, super phosphates and partially acidulated phosphate rocks; and

c) at least one cationic or amphoteric surfactant in an amount in the range of from 0.001 to 3 wt. %, based on the total weight of the fertilizer composition, wherein the cationic or amphoteric surfactant is dispersed throughout the fertilizer composition.

7. A fertilizer composition as claimed in claim 6, wherein the at least one cationic or amphoteric surfactant comprises a nitrogen-containing cationic surfactant.

8. A fertilizer composition as claimed in claim 7, wherein the at least one cationic or amphoteric surfactant comprises an ethylene or propylene oxide adduct of an aliphatic amine, said aliphatic amine containing 12 to 20 carbon atoms.

9. A fertilizer composition as claimed in claim 6, wherein the at least one cationic or amphoteric surfactant is present in an amount in the range of from 0.001 wt. % to 0.05 wt. % with respect to the weight of the overall fertilizer composition.

10. A fertilizer composition as claimed in claim 6, wherein the elemental sulphur is present in the form of particles having a size in the range of from 1 to 200 microns.

11. A fertilizer composition as claimed in claim 10, wherein the elemental sulphur is present in the form of particles having a size in the range of from 5 to 150 microns.

12. A fertilizer composition as claimed in claim 11, wherein the elemental sulphur is present in the form of particles having a size in the range of from 30 to 100 microns.