An improved solvent system for the formulation and application of N-alkyl thiophosphoric triamide urease inhibitors. These formulations provide safety and performance benefits relative to existing alternatives and enable storage, transport and subsequent coating or blending with urea based or organic based fertilizers. These formulations are comprised primarily of environmentally friendly aprotic and protic solvents (particularly dimethyl sulfoxide and alcohols/polyols) to stabilize the urease inhibitor.

An inhibitor composition contains alkyl thiophosphoric triamide (or a mixture of alkyl thiophosphoric triamide and dicyandiamide), dissolved in a liquid medium comprising at least one organic solvent, at least one amine stabilizer and, optionally, at least one dye and/or at least one odor masking agent, is useful in making fertilizer compositions and in a method of fertilizing target plants.

A composition comprising: (A) a mixture comprising at least one (thio)phosphoric acid triamide according to the general formula (I) R.sup.1R.sup.2N—P(X)(NH.sub.2).sub.2, wherein X is oxygen or sulfur; R.sup.1 is a C.sub.1 to C.sub.20 alkyl, C.sub.3 to C.sub.20 cycloalkyl, C.sub.6 to C.sub.20 aryl, or dialkylaminocarbonyl group; R.sup.2 is H, or R.sup.1 and R.sup.2 together with the nitrogen atom linking them define a 5- or 6-membered saturated or unsaturated heterocyclic radical, which optionally comprises 1 or 2 further heteroatoms selected from the group consisting of nitrogen, oxygen, and sulfur, and (L1) at least one amine selected from the group consisting of (L10), (L11), (L12), (L13), (L14), (L15), (L16), (L17), (L18), (L19), (L20), (L21), (L22), (L23), (L24), and (L29).

Reaction products and methods for making and using such reaction products are provided. For example, a reaction product comprising an adduct formed from urea, formaldehyde, and a urease inhibitor is described, which can be provided in various forms. For example, such a reaction product can be in the form of a solid or solution. Such a reaction product can also be combined with one or more additional components, including but not limited to, additional urease inhibitor and/or a nitrogen-based fertilizer composition.

An inhibitor composition contains alkyl thiophosphoric triamide (or a mixture of alkyl thiophosphoric triamide and dicyandiamide), dissolved in a liquid medium comprising at least one organic solvent, at least one amine stabilizer and, optionally, at least one dye and/or at least one odor masking agent, is useful in making fertilizer compositions and in a method of fertilizing target plants.

Compositions include dicyandiamide (DCD), N—(N-butyl) Thiophosphoric Triamide (NBPT), and styrene-maleic anhydride copolymer in a solution. Agricultural fertilizer compositions contain the DCD, NBPT and styrene-maleic anhydride copolymer composition in combination with a fertilizer.

An improved solvent system for the formulation and application of N-alkyl thiophosphoric triamide urease inhibitors. These formulations provide safety and performance benefits relative to existing alternatives and enable storage, transport and subsequent coating or blending with urea based or organic based fertilizers. These formulations are comprised primarily of environmentally friendly aprotic and protic solvents (particularly dimethyl sulfoxide and alcohols/polyols) to stabilize the urease inhibitor.

An improved solvent system for the formulation and application of N-alkyl thiophosphoric triamide urease inhibitors. These formulations provide safety and performance benefits relative to existing alternatives and enable storage, transport and subsequent coating or blending with urea based or organic based fertilizers. These formulations are comprised primarily of environmentally friendly aprotic and protic solvents (particularly dimethyl sulfoxide and alcohols/polyols) to stabilize the urease inhibitor.

Method for obtaining a fertilizer composition comprising (iii) at least one urea-containing fertilizer (1); and (iv) at least one (thio)phosphoric acid triamide (2) according to general formula (I) wherein X.sup.1 is O or S; R.sup.1 is C.sub.1-C.sub.20-alkyl, C.sub.3-C.sub.20-cycloalkyl, C.sub.6-C.sub.20-aryl, C.sub.6-C.sub.20-aryl-C.sub.1-C.sub.4-alkyl, or C.sub.1-C.sub.6-(di)alylaminocarbonyl; R.sup.2 is H, C.sub.1-C.sub.20-alkyl, C.sub.3-C.sub.20-cycloalkyl, C.sub.6-C.sub.20-aryl, C.sub.6-C.sub.20-aryl-C.sub.1-C.sub.4-alkyl, or C.sub.1-C.sub.6-(di)alkylaminocarbonyl; or R.sup.1 and R.sup.2 together with the nitrogen atom linking them define a 5- or 6-membered saturated or unsaturated heterocyclic radical, which optionally comprises 1 or 2 further heteroatoms selected from the group consisting of N, O, and S; and R.sup.3, R.sup.4, R.sup.5, and R.sup.6 are independently of each other selected from the group consisting of H and C.sub.1-C.sub.4-alkyl; comprising the steps: a) providing a solid and/or liquid premix (P) wherein the premix (P) comprises at least one urea-containing fertilizer (1) and at least one (thio)phosphoric acid triamide (2) in a weight ratio of 1:6 to 400:1 based on the total weight of all urea-containing fertilizers (1) and of all (thio)phosphoric acid triamides (2), wherein at least 85 wt % of the premix (P) (a1) is not a melt; and (a2) is not obtained via melting of any of the at least one urea-containing fertilizer (1) or melting of any of the at least one (thio)phosphoric acid triamide (2); and (a3) is not obtained via dissolving or mixing the at least one (thio)phosphoric acid tri-amide (2) in/with a solvent (S) having a boiling point of less than 100° C., and b) adding the premix (P) to a melt (Q) comprising urea-containing fertilizer (1) by forming a mixture (M) n comprising the at least one urea-containing fertilizer (1) and the at least one (thio)phosphoric acid triamide (2), wherein the residence time of the thus formed mixture (M) before granulation is adjusted such that the at least one (thio)phosphoric acid tri-amide (2) is not or almost not decomposed in the mixture (M); and c) forming solid fertilizer granules by use of the mixture (M) comprising the at least one urea-containing fertilizer (1) and the at least one (thio)phosphoric acid triamide (2).

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Provided herein is a process for isolating at least one (thio)phosphoric acid derivative, which has a boiling point of at least 70 C., from a product mixture including the at least one (thio)phosphoric acid derivative, at least one salt selected from ammonium salts and alkali metal chlorides, at least one polar solvent selected from the group consisting of ester solvents and ether solvents, and optionally at least one HCl scavenger; wherein the process is based on first dissolving the (thio)phosphoric acid derivative to be able to remove the at least one salt, and then causing solids formation of the (thio)phosphoric acid derivative.