DE965332C - Process for the production of fertilizers containing potash, phosphoric acid and nitrogen - Google Patents

Description

Process for the production of potash, phosphoric acid and nitrogen containing Fertilizers It is already known superphosphate with Kaliui-n, sulfate and ammonium sulfate treat to obtain fertilizers containing primary potassium phosphate and / or primary Contain ammonium sulfate. Here, potassium sulfate is formed from the sulfate residue and / or ammonium sulphate precipitated calcium sulphate, which so far has generally not been found further use.

It has also been suggested that potassium ammonium sulfate, i.e. H. Solutions containing potassium sulphate and ammonium sulphate can be obtained from potassium chloride and calcium sulphate in a two-stage process. Here, potassium chloride or a salt mixture containing potassium chloride is first reacted with gypsum, ammonia and carbon dioxide at temperatures of more than 40 'to form syngenite, calcium carbonate and aminolitil-nchiloride. After the ammonium chloride solution has been separated off, the syngenite-calcium carbonate mixture in a solution saturated with potassium sulfate and ammonium sulfate with ammonia and carbon dioxide is converted into a potassium ammonium sulfate solution and precipitated calcium carbonate.

It has been found that fertilizers containing potassium, phosphoric acid and nitrogen can be produced particularly advantageously with a mixture of potassium ammonium sulphate solution and precipitated calcium carbonate, if superphosphate is stirred and heated with a mixture of dissolved potassium ammonium sulphate and precipitated Calcitimcarbonat reacted, the Kalitmichlorid and calcium sulfate ammonium sulphate solution of potassium sulfate produced by Aufsehlämmung in a saturated during the treatment with Ainmoniak, and carbon dioxide, after which the in the implementation of potassium ammonium sulfate - precipitating mixture with superphosphate and separated from the solution - calcium carbonate Calcium sulfate, in turn, is used to produce potassium ammonium sulfate from potassium chloride, while the separated solution is processed into solid fertilizers. In this reaction, the potassium ammonium sulfate reacts with the water-soluble monocalcium phosphate of the superphosphate and, when an appropriate amount of calcium carbonate is added, forms secondary potassium ammonite phosphate.

This multi-nutrient fertilizer is a compound fertilizer, itt, el, because it contains the three necessary fertilizer components potassium, nitrogen and phosphoric acid. This compound fertilizer can be brought to the desired nutrient ratio by adding potassium ammonium sulfate and / or ammonium nitrate of 40 parts of potassium ammonium phosphate, 35 parts of potassium ammonium sulphate and: 25 parts of ammonium nitrate a compound fertilizer with about 15 0 / a N, 15 0/0 P2 0, and 2 1% K2 0.

In the process of the invention for producing potassium ammonium phosphate containing fertilizers is neither an evaporation of the potassium, ammonium sulfate solution A separation of the calcium aerosol contained therein is also necessary. the Rather, a mixture of the two ingredients is used directly to treat superphosphate used. The calcium sulphate which precipitates out is fed into the process cycle traced back to the manufacture of potassium ammonium sulfate, in different ways Practically completely avoid operating losses' of potash and nitrogen compounds.

Another advantage of the procedure according to the invention is that no sulfuric acid is required for the production of the potassium sulfate and ammonium sulfate used as the starting material. Inexpensive potassium chloride can be used for the potassium content of the mixed fertilizer, which was previously not possible. In this way, the already known production of potassium phosphate from phosphoric acid, animoinium sulfate and potassium sulfate is considerably more economical. Example From potassium chloride and precipitated Caleiumsulfat was first syngenite (about S 'K2 S 04 "H2 (" produced 04, which in a gesättiggten KaEumsulfat-Ammoni-umsulfa, t-Lösun, - in Kaliumammoniumstilfat and Calciui-nearbonat was cut from the. The reaction solution obtained in this way was separated off 315 9 l, 7-aluminum aminonium sulfate and divided into three portions of twice 7-9 and once 161 g . 400 g of superphosphate with 18.1 '/ e P, 05 (72.5 g of M205) were then added. with 77 g of potassium ammonium sulfate (23.6 K, 0 and 9.15 -N) in 10000 H "0: stirred for 2 hours at 50 to 60 'and filtered. The residue was washed out with about 300 cm3 of water.

720 CM3 mother solution and 3 1 0 c1113 cover solution were obtained, together 1030 c1113 = 1 135 g. This solution contained in plant nutrients: K20 = 2.05 "/ o = 23J5 9 (about 98.7" / 0 from Eillsai7) P2 05 = 6, O / o, = 69.3 9 (about 95.7 0/0 from the insert) INT = 0.62 104 = 7.00 9 (about 99.5 "/ 0 from the insert) Another 77 g of potassium ammonium sulfate were added to this solution and 40 9 of Cal # ciun -'-carbonate were added from the production The mixture was heated to the boil, whereby carbonic acid escaped. The mixture was then evaporated to dryness. 184 g of a non-hygroscopic mixture containing 37.6 % P2 051 were obtained 2 5.4 0/0 K2 01 7.6 % N.

If the remaining 161 g of potassium ammonium sulphate and 1 1 5 g of ammonium nitrate of any kind were added to this product, then 46o g of a full finger with 15 1/0, P2 05, 1 5% and: 21 % K # 0 were obtained.

Claims (4)

PATENT CLAIM: A process for the production of potash, phosphoric acid and nitrogen-containing fertilizers from Kalitimammoniumsulfat and Superpliosphat, characterized in that superphosphate is reacted under stirring with a mixture of potassium ammonium sulfate solution and overall fälltem Calcitimcarbonat, the saturated from Kaliunichlorid and calcium sulfate through a slurry in a. Potassium sulphate-ammonium sulphate solution and treatment with ammonia and carbon dioxide are produced, whereupon the calcium sulphate which precipitates out with superphosphate and is separated from the solution during the conversion of the potassium ammonium sulphate - calcium carbonate - is used again to produce potassium ammonium sulphate from potassium dichloride. used while the separated solution is processed on solid fertilizers. Into consideration. printed publications .: German Patent Publication Nos. 300 022, 404 622, 533 857, 563 459; British patent specification no. 34864o "5 586 / igio; USA.-Patent No. 1 948 520; Schucht:" Die Fabrikation des Superplinsphates ", 4th edition, 1 926, p. 202 and 2 1 1.