Urea and nitrogen stabilizer compositions and methods and systems of making and using thereof

Abstract

This invention relates to an improved urea-nitrogen stabilizer composition and methods, systems and apparatti for making thereof. The nitrogen stabilizer composition is incorporated into molten urea to result in a composition that contains less biuret, NMP, nitrogen stabilizer and/or impurities and provides an effective solid fertilizer. These compositions are useful in in odor control.

What we claim is: 
     
         1 . A stabilized urea composition comprising:
 a. urea; and   b. a nitrogen stabilizer composition comprising NBPT having a purity of at least 90% and a carrier selected from alkanol, alkenol, hydroxyalkyl aryl, glycol, glycol ether, glycol ester, glycerol, poly(alkylene glycol), poly(alkylene glycol) ether, poly(alkylene glycol) ester, alkanolamine, hydroxy acid, DMSO, N-methyl 2-pyrrolidinone (NMP), and mixtures thereof;   wherein the concentration of NBPT is less than 0.2 weight percent based on the total weight of the stabilized urea composition.   
     
     
         2 . The composition of  claim 1 , wherein said nitrogen stabilizer composition further comprises a nitrification inhibitor. 
     
     
         3 . The composition of  claim 2 , wherein said nitrification inhibitor is selected from thiourea, 1-mercapto-1,2,4-triazole, 2-amino-4-chloro-6-methyl-pyramidine, 2,4-diamino-6-trichloro-methyltriazine, 2-chloro-6-(trichloromethyl-pyridine), 3,4-dimethylpyrazole phosphate (DMPP), 1H-1,2,4-triazole, 4-amino-1,2,4-triazole, 3-methylpyrazole, azadirachta indica Juss (Neem), and nitrapyrin. 
     
     
         4 . The composition of  claim 2  wherein said nitrification inhibitor is dicyandiamide (DCD). 
     
     
         5 . The composition of  claim 1 , wherein said stabilized urea composition is in liquid form. 
     
     
         6 . The composition of  claim 1 , wherein said stabilized urea composition is in solid form. 
     
     
         7 . The composition of  claim 5 , wherein said urea is molten urea, urea ammonium nitrate (UAN), or a mixture thereof. 
     
     
         8 . The composition of  claim 6 , wherein a portion of said nitrogen stabilizer composition is present on the surface of said urea and further wherein said urea is a solid prill, granule, pellet, or pastille. 
     
     
         9 . The composition of  claim 1 , wherein the NBPT has a purity of at least 95%. 
     
     
         10 . The composition of  claim 1 , wherein the NBPT has a purity ranging from 95% to about 98%. 
     
     
         11 . The composition of  claim 10 , wherein the nitrogen stabilizer further comprises dicyandiamide (DCD). 
     
     
         12 . The composition of  claim 1 , wherein the concentration of NBPT is between 0.001 weight % and 0.2 weight % based on the total weight of the stabilized urea composition. 
     
     
         13 . The composition of  claim 1 , wherein the carrier is glycol. 
     
     
         14 . The composition of  claim 13 , wherein the glycol is propylene glycol. 
     
     
         15 . The composition of  claim 1 , wherein the carrier is a mixture of propylene glycol and NMP. 
     
     
         16 . The composition of  claim 1 , wherein the carrier is alkanolamine, which is selected from ethanolamine, diethanolamine, and triethanolamine. 
     
     
         17 . A composition comprising:
 a. NBPT having a purity of at least 90%, and   b. a carrier selected from alkanol, alkenol, hydroxyalkyl aryl, glycol, glycol ether, glycol ester, glycerol, poly(alkylene glycol), poly(alkylene glycol) ether, poly(alkylene glycol) ester, alkanolamine, hydroxy acid, DMSO, N-methyl 2-pyrrolidinone (NMP), and mixtures thereof, wherein the concentration of NBPT in the carrier ranges from 1 weight % to 55 weight %.   
     
     
         18 . The composition of  claim 17 , wherein the carrier is glycol. 
     
     
         19 . The composition of  claim 18 , wherein the glycol is propylene glycol. 
     
     
         20 . The composition of  claim 17 , wherein the carrier is a mixture of propylene glycol and NMP. 
     
     
         21 . The composition of  claim 17 , wherein the composition further comprises dicyandiamide (DCD). 
     
     
         22 . The composition of  claim 17 , wherein the NBPT has a purity of at least 95%.