# US 4,395,273 A · Preparation of multi-trace element fertilizers

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 4,395,273 A
- Document ID: US4395273A
- Status: Granted
- Kind: A
- Application number: 06/322,672
- Filed: 1981-11-18
- Granted: 1983-07-26
- Earliest claimed: 1980-11-28
- Assignees: BASF SE
- Inventors: Bernd Leutner; Bernhard Purucker; Eberhard Rother; Geerd F. Juergens; Dieter Wagner
- Web page: https://patentgrep.com/patent/US4395273A

## CPC

- C05D 9/02: containing trace elements
- Y10S 71/02: Chelating agent
- C05D: INORGANIC FERTILISERS NOT COVERED BY SUBCLASSES C05B, C05C; FERTILISERS PRODUCING CARBON DIOXIDE
- Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS

## Abstract

A multi-trace element fertilizer which contains magnesium as a further nutrient and in which the complex-forming trace elements are present in the form of anionic chelates with one or more N-carboxyalkylaminoacids is prepared by a process wherein the N-carboxyalkylaminoacids are reacted, in the presence of water, with the trace elements or trace element compounds in a molar ratio of N-carboxyalkylaminoacids to trace elements or trace element compounds of not less than 0.8:1, at least 20% by weight of the trace element compounds being oxides, hydroxides and/or carbonates. At the same time, or subsequently, the pH of the solution is brought to 3.5-6 by adding a member selected from the group consisting of magnesium oxide, hydroxide and carbonate. A maximum of 50 equivalent percent of the magnesium compound may however be replaced by a member selected from the group consisting of alkali metal oxides, hydroxides and carbonates and ammonia.

## Claims

### Claim 1

A process for the preparation of a multi-trace nutrient fertilizer which contains magnesium as a further nitrient and in which the complexforming trace elements are present in the form of anionic chelates with one or more N-carboxyalkylaminoacids, which comprises: reacting the N-carboxyalkylaminoacids, in the presence of water, with the trace elements or trace element compounds in a molar ratio of N-carboxyalkylaminoacids to trace elements or trace element compounds of not less than 0.8:1, at least 20% by weight of the trace element compounds being oxides, hydroxides and/or carbonates to form an anionic trace element chelate, and at the same time, or subsequently, raising the pH of the solution to 3.5-6 by adding a magnesium compound selected from the group consisting of magnesium oxide, hydroxide and carbonate, whereby said magnesium compound reacts with said anionic trace element chelate.

### Claim 2 (depends on 1)

The process of claim 1, wherein the solution obtained after the reaction is solidified by abstracting water.

### Claim 3 (depends on 2)

The process of claim 2, wherein the water is abstracted by spray-drying or fluidized bed spray drying.

### Claim 4 (depends on 2)

The process of claim 2, wherein the abstraction of water is taken to a residual content of 4-10% by weight.

### Claim 5 (depends on 1)

The process of claim 1, wherein a maximum of 50 equivalent percent of the magnesium compound required is replaced by a member selected from the group consisting of alkali metal oxides, hydroxides and carbonates and ammonia.

### Claim 6 (depends on 1)

The process of claim 1, wherein the amount of water that is present in the process, is sufficient to form a solution of the reaction products.