DD287026A5 - METHOD FOR PRODUCING MICRONAUTH-CONTAINING LIQUID NITROGEN THREADENERS - Google Patents

Abstract

The invention relates to the preparation of urea or ammonium nitrate-urea Duengeloesungen with micronutrients as lignosulfonates by reaction of calcium lignosulfonate with metal sulfate, bypassing a calcium sulfate. A process is proposed in which the costly work step "calcium sulfate removal" is avoided and the products of formation can be used directly without further intermediates as liquid fertilizers with chelated micronutrients. Fertilizer, liquid; Urea solutions; Ammonium nitrate-urea solutions; micronutrient; chelates; lignin; Metal sulfates; Calcium sulfate deposition}

Description

Field of application of the invention

The invention relates to a process for the preparation of liquid fertilizers containing micronutrients from aqueous urea or ammonium nitrate-urea solutions and to calcium lignosulfonates and metal sulfates.

Characteristic of the known technical solutions

The use of liquid nitrogen agents such as urea solution or ammonium nitrate-urea solution is widely used in agriculture and horticulture.

It is known to add other nutrients, especially micronutrients, to these solutions. For efficiency reasons, these mixtures, which thus consist of various fertilizer components, are applied in one operation as a common aqueous solution (Nevskaja, VN; Chimizacja sel'skogo chozjajstwa-Moskva (1988) 3, pp. 30-32; Fibian, Borchmann, Wiss. Z. Univ Rostock 22 [19731 S. 351-355].

Micronutrients such as copper, zinc, iron and magnesium are important plant nutrients required for healthy growth and high yields. To increase their effectiveness, they are often bound to so-called chelating agents such as EDTA, NTA, DTPA and HEEDTA and used as a complex compound.

(US-PS 2929700; DE-PS 2313921; DD-PS 210449; DE-PS 2535985)

In addition to synthetic complexing agents, lignin sulfonic acid can also be used as a good plant tolerant natural product.

Lignosulfonic acid is mainly produced as calcium salt in the process of cellulose extraction. It thus has waste as compared to the synthetic compounds cost-effective conditions for the production of micronutrient compounds.

(U.S. Patent No. 2,929,700; U.S. Patent No. 3,344,505)

So z. B. the common application of Kupferligninsulfonatpräparaten with ammonium nitrate-urea solution recommended.

(User guideline Coinbilignat-Cu, VEB CWC Coswig / Anhalt, 1989)

Furthermore, it is known that for the preparation of micronutrient compounds of Cu, Mn, Zn, Fe and Mg as Ligninsulfonate the reaction of Ca lignosulfonate is carried out with the metal sulfates in aqueous solution.

The precipitated CaSO ₄ 2 H] O is separated and there is a solution of the corresponding lignosulfonates (DD-PS 96226).

Disadvantageous in the production of Metalligninsulfonaten from sulfuric acid metal salts and Ca lignosulfonate the inevitable operation of the gypsum separation by means of filtration, centrifugation or other methods. This process step is complicated by the fact that concentrated lignosulfonate solution is highly viscous.

Particularly unfavorable for the separation of gypsum precipitate proves to be the fact that the gypsum fractions in the solution require a longer period for the precipitation and also occur after completion of separation sequestration. Overall, it is thus an unfavorable time-consuming operation.

Object of the invention

The aim of the invention is to present a cost-effective process for producing aqueous solutions of ammonium nitrate and / or urea and calcium lignosulfonates and metal sulfates, which avoids the "plaster removal" step and in which the products of origin can be utilized directly as liquid fertilizers with micronutrients.

Explanation of the essence of the invention

It is the object of the invention to provide a cost-effective ancestor for the preparation of aqueous solutions of calcium Lignin3ulfonat, metal sulfates, ammonium nitrate and / or urea, in which the unfavorable labor shyness, gypsum separation "is avoided and without further intermediates directly usable urea or Ammonnitrat- Urea solutions are formed containing micronutrients chelated with lignin sulfonic acid.

The object is achieved according to the invention such that an aqueous urea solution or an aqueous ammonium nitrate Urea solution calcium lignosulfonate submitted and then the micronutrient as metal sulfate or Metal sulfate solution in the molar ratio of micronutrient calcium is added from 0.1: 1 to 22: 1, wherein the total content of the Liquid fertilizer is 0.05-8% micronutrient. Surprisingly, it has been found that a direct reaction of calcium lignosulfonate and metal sulfate in the Urea or ammonium nitrate urea solution without gypsum precipitation is possible if certain concentration conditions

be respected.

In this way, the solubility product of CgSO ₄ can be changed to such an extent that the gypsum precipitation

omitted.

By avoiding the "gypsum separation" step, the production of urea or ammonium nitrate-urea Solutions that contain micronutrients chelated with Ugninsulfonsäure much less expensive. The liquid fertilizers produced by the process according to the invention with the micronutrients Cu, Mn, Zn, Fe and Mo in Form of Metalligninsulfonaten have the advantage that they urea or an ammonium nitrate-urea mixture in any Containing ratio to each other in aqueous solution with a total concentration of 8-32% nitrogen and the content of Micronutrients 0.05 to 8%. A'iiführungsbeltplele

The invention will be explained below with reference to embodiments, without limiting the generality.

Belsplbl 1

In 100 g of an aqueous solution consisting of 40 parts by mass of ammonium nitrate, 30 parts by mass of urea and 30 parts by mass of water

1.12 g CuSO ₄ - 5H ₂ O are dissolved. Thereafter, 3.8 g of a 50% aqueous solution of Ca lignosulfonate with a

Content of 2% Ca at 20 ° C ur. >, intensive stirring within 10 min registered. The result is a clear brown solution with a Cu content of 0.26%. After 72 hours, the solution is still clear Rainfall. After addition of NHj no Kupferfertetraminkomplex, the typical blue coloration remains. Example 2

In a 100g at 20 ⁰ C saturated solution of urea (24.2% N) is dissolved 2.71 g of ZnSO ₄ and 18.9 g Ca lignosulfonate with a Ca content of 2% under the same conditions as in Example. 1 The result is a dark brown, consistently clear solution with a Zn-content of 0.507%.

Example 3

In 100 g of a 2O ⁰ C saturated urea solution (24.2% N) 5.78 g ZnSO ₄ 7 H ₂ O and 8.84 g Ca lignosulfonate are dissolved with a Ca content of 2% with vigorous stirring. After about 15 minutes, a dark brown clear solution with a content of 1.14% Zn is formed.

Example 4 In 100 g of an aqueous, containing 32% N ammonium nitrate-urea solution (ratio NH ₄ NOaXO (NH ₁ I ₂ = 4: 3))

0.440 g ZnSO ₄ -7H ₂ O 0.498 g FeSO ₄ -7H ₂ O 0.439 g MnSO ₄ 5H ₂ O and 1.014 g MgSO ₄ 7H ₂ O and 18.550 g Ca lignosulfonate with 2% Ca

solved. After intensive stirring, a dark brown, consistently clear solution with a metal content of 0.31%, of which 0.083% Zn, 0.083% Fe, 0.083% Mn and 0.83% Mg, is formed.

Examples In 100 g of an aqueous ammonium nitrate-urea solution containing 8% N (ratio NH ₄ NO ₃ : CO (NH ₂ ) j = 1: 4)

1.683 MgSO ₄ 7H ₂ O and 13.65 g Ca lignosulfonate dissolved. The result is a dark brown, consistently clear solution with 0.14% Mg.

Achieve

In 100 g of a saturated urea solution at 20 ⁰ C (24.2% N) 49.55g CuSO ₄ · 5H ₂ O and 18.9g of an aqueous 50% Dissolve Ca lignosulfonate solution with 2% Ca with vigorous stirring. The result is a consistently clear, dark brown solution with 14.4% N and 7.49% Cu. Example 7 In \ 00g of an aqueous solution consisting of 40 parts by weight of ammonium nitrate, 30 parts by mass of urea and 30 parts by mass of water

1.12 g CuSO ₄ .5H ₂ O are dissolved. Thereafter, 89.5 g of a 50% aqueous solution of Ca lignosulfonate with a

Content of 2% Ca registered at 20 ° C with intensive stirring within 10min. The result is a dark brown, consistently clear solution with a Cu content of 0.26%.

Claims (4)

1. A process for preparing mlkronährstoffhaltiger liquid fertilizer from aqueous urea or ammonium nitrate-urea solutions, metal sulfate and Calciumligninsulfonat, characterized in that the preparation of the micronutrient compounds by reaction of calcium lignosulfonate and metal sulfonate in urea or ammonium nitrate-urea solutions is made. 2. The method according to claim 1, characterized in that the urea or ammonium nitrate I larnstoff solutions have a nitrogen content of 8-32%. 3. The method according to claim 1 and 2, characterized in that as metal sulfonate Cu, Mn, Zn, Fe and Mg are used individually or in admixture in solid or dissolved form and the metal concentration in the liquid fertilizer 0.05-8.0% , 4. The method according to Ancpruch 1-3, characterized in that the molar ratio of micronutrient to calcium in the reaction is 0.1: 1 to 22: 1.