PROCESS FOR THE PRODUCTION OF A FERTILIZER

Abstract

Process for the production of a compound comprising potassium phosphite comprising the steps of (a) reacting carboxylic acid of the formula R—(C(═O)OH).sub.n with phosphorous trichloride (PCl.sub.3) towards a mixture comprising phosphorous acid (H.sub.3PO.sub.3) and acid chloride of the formula R—(C(═O)Cl).sub.n; wherein R is a linear or branched alkyl or alkanediyl group with 1-20 carbon atoms and n is 1 or 2, (b) subjecting said mixture to a separation step, thereby obtaining (i) a fraction comprising crude phosphorous acid (H.sub.3PO.sub.3) and (ii) a fraction comprising acid chloride, (c) combining water, a potassium compound selected from KOH, KHCO.sub.3 and K.sub.2CO.sub.3, and the fraction comprising crude phosphorous acid, thereby forming an aqueous solution comprising potassium phosphite, and (d) removing organic compounds from said aqueous solution.

Claims

1-12. (canceled)

13-31. (canceled)

32. A process for producing an aqueous solution comprising potassium phosphite chosen from K.sub.2HPO.sub.3, KH.sub.2PO.sub.3, and combinations thereof, said method comprising the steps of: a. reacting a carboxylic acid of the formula R—(C(═O)OH).sub.n with phosphorous trichloride (PCl.sub.3) to make a mixture comprising phosphorous acid (H.sub.3PO.sub.3) and an acid chloride of the formula R—(C(═O)Cl).sub.n; wherein R is a linear or branched alkyl or alkanediyl group with 1-20 carbon atoms and n is 1 or 2 or R is a cyclohexyl group and n is 1, b. subjecting the mixture to a separation step, thereby obtaining (i) a fraction comprising crude phosphorous acid (H.sub.3PO.sub.3) and (ii) a fraction comprising the acid chloride, and c. combining water, a potassium compound selected from KOH, KHCO.sub.3 and K.sub.2CO.sub.3, and the fraction comprising the crude phosphorous acid, thereby forming an aqueous solution comprising the potassium phosphite and having a pH below 5, and d. removing organic compounds.

33. The process according to claim 32, wherein in step c) the fraction comprising crude phosphorous acid is dosed to an aqueous solution of the potassium compound.

34. The process according to claim 32, wherein R is a linear or branched alkyl or alkanediyl group with 3-17 carbon atoms.

35. The process according to claim 34, wherein R has 7-17 carbon atoms.

36. The process according to claim 32, wherein the carboxylic acid comprises isobutanoic acid, n-butanoic acid, lauric acid, 3,5,5-trimethylhexanoic acid, pivaloic acid, valeric acid, n-hexanoic acid, n-octanoic acid, 2-ethylhexanoic acid, (neo)decanoic acid, (neo)heptanoic acid, or cyclohexane carboxylic acid.

37. The process according to claim 32, wherein the potassium compound is KOH.

38. The process according claim 32, wherein n is 1.

39. The process according to claim 32, comprising the additional step of reacting the acid chloride with hydrogen peroxide and an alkali metal salt to form a diacyl peroxide.

40. The process according to claim 32, comprising the additional step of reacting the acid chloride with a peroxyacid and an alkali metal salt to form a diacyl peroxide.

41. The process according to claim 40, wherein the peroxyacid comprises peracetic acid, perpropionic acid, or perlauric acid.

42. The process according to claim 32, comprising the additional step of reacting the acid chloride with an organic hydroperoxide and an alkali metal salt to form a peroxyester.

43. The process according to claim 42, wherein the organic hydroperoxide comprises tert-butyl hydroperoxide, tert-amyl hydroperoxide, cumyl hydroperoxide, 2,2,4,4-tetramethylbutyl hydroperoxide, 1,3-bis(2-hydroperoxypropan-2-yl)benzene, 1,4-bis(2-hydroperoxypropan-2-yl)benzene, 2,5-dihydroperoxy-2,5-dimethylhexane, 2,5-dihydroperoxy-2,5-dimethylhex-3-yne, and mixtures thereof.

44. The process according to claim 32, wherein step d comprises removing organic compounds from the aqueous solution.

45. The process according to claim 44, further comprising the step of reacting the acid chloride with (i) hydrogen peroxide and an alkali metal salt to form a diacyl peroxide, (ii) a peroxy acid and an alkali metal salt to form a diacyl peroxide, or (iii) an organic hydroperoxide and an alkali metal salt to form a peroxyester.

46. The process according to claim 44, wherein R has 7-17 carbon atoms, n is 1, and the potassium compound is KOH.

47. The process according to claim 44, wherein the potassium phosphite comprises KH.sub.2PO.sub.3.

48. The process according to claim 44, wherein the potassium phosphite comprises K.sub.2HPO.sub.3.

49. A process for producing an aqueous solution comprising KH.sub.2PO.sub.3, the method comprising the steps of: a. reacting dodecanoic acid with phosphorous trichloride (PCl.sub.3) to make a mixture of phosphorous acid (H.sub.3PO.sub.3) and dodecanoyl chloride, b. subjecting the mixture to a separation step, thereby obtaining (i) a fraction of crude phosphorous acid (H.sub.3PO.sub.3) and (ii) a fraction of dodecanoyl chloride, and c. combining water, KOH, and the fraction of the crude phosphorous acid (H.sub.3PO.sub.3), thereby forming an aqueous solution of KH.sub.2PO.sub.3 and having a pH below 5, and d. removing organic compounds.

50. The process of claim 49 wherein the dodecanoic acid is reacted with the phosphorous trichloride (PCl.sub.3) in a molar ratio of about 2.6:1.2; and step d) removes organic compounds via filtration such that a total weight of organic compounds is less than about 0.1 wt % as determined using NMR.

51. The process of claim 49 wherein about 1 mole of KOH is added per about 1 mole of the crude phosphorous acid (H.sub.3PO.sub.3).

Description

EXAMPLES

Example 1

Steps a) and b)

[0050] Dodecanoic acid (518 g, 2.59 mol) was charged to a three-necked round bottom flask with bottom drain equipped with a mechanical overhead stirrer, a thermometer, a reflux cooler, a dropping funnel and a nitrogen purge. The reflux cooler was connected to a double wash vessel to trap HCl and PCl3 (first flask was empty; the second one was filled with water).

[0051] Dodecanoic acid was heated to 63° C., resulting in a transparent melt. PCl3 (100 ml, 1.15 mol) was added via the dropping funnel in 20 to 30 minutes; the temperature was maintained at 63° C. Stirring was stopped after the addition of the PCl3 and the mixture was left to stand for 3 hours at 63° C. The warm crude H.sub.3PO.sub.3 solution (containing PCl3 and several polyphosphorous compounds) was collected at the bottom of the flask and this phase was drained off as a slightly hazy and viscous liquid (73 g, 890 mmol, 78% yield). The remaining crude dodecanoyl chloride (518 g, 2586 mmol, 102%) was isolated as a colorless hazy liquid and was used as such in the production of dilauroyl peroxide.

Steps c) and d)

[0052] Water (13.32 g) and KOH (50.0 g, 45 wt %, 0.40 mol) were charged to a 100 mL beaker, equipped with a bottom drain and thermometer. The solution was stirred with a mechanical overhead stirrer at 600 rpm. The beaker was placed in a 1000 mL beaker containing ice water and was cooled down to 5° C. 47 gram of the crude H.sub.3PO.sub.3 solution of step b) was added to the stirred solution. The dosing speed was set at such a rate that the temperature never exceeded 30° C. (dosing took 20 minutes). During said dosing, a white precipitate was formed. After the dosing, stirring was stopped and the reaction mixture was cooled to 10° C. The chilled mixture was filtered under reduced pressure over a G3 glass filter. The resulting slightly hazy solution was subsequently filtered over a G4 glass filter. The second filtration yielded a clear colorless 50 wt % KH.sub.2PO.sub.3 solution (88.2 g, 92% yield). Total organics <0.1 wt % (by NMR); total chloride content 0.36 wt %.

Example 2

[0053] Steps a) and b) of Example 1 were Repeated.

[0054] Water (16.5 g) was carefully added to stirred crude H.sub.3PO.sub.3 (38.4 g, 0.47 mol). The temperature of the mixture rose quickly, which resulted in HCl formation (the crude H.sub.3PO.sub.3 contained some PCl3 residues). The vapours were removed by a nitrogen purge. When the addition was completed, the resulting hazy, hot 70 wt % H.sub.3PO.sub.3 solution was left to cool to room temperature. During cooling, an organic phase accumulated on the top of the solution. The phases were separated by draining off the aqueous H.sub.3PO.sub.3-containing phase (bottom layer).

[0055] 47 gram of the so-obtained 70 wt % H.sub.3PO.sub.3 solution (0.40 mol H.sub.3PO.sub.3) was charged to a 100 mL beaker, equipped with a bottom drain and thermometer. The solution was stirred with a mechanical overhead stirrer at 1400 rpm. The beaker was placed in a 1000 mL beaker containing ice water and was cooled down to 5° C. A 45 wt % KOH solution (50 gram, 0.40 mol KOH) was added in dropwise fashion via a dropping funnel at such a rate that the temperature was kept below 25° C. The addition took 24 minutes. After this addition, stirring was stopped and a slightly hazy solution with floating solids on top was observed. The slightly hazy solution was drained off and the solids were left behind in the beaker. The obtained KH.sub.2PO.sub.3 solution (50 wt %, density=1.38 g/ml) was subsequently filtered over a G4 glass filter, resulting in a clear and colorless solution (93.94 gram KH.sub.2PO.sub.3).

[0056] While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the various embodiments in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment as contemplated herein. It being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the various embodiments as set forth in the appended claims.