| abstract |
A process for the preparation of a spray-dried powder containing at least one glycine-N,N-diacetic acid compound of a formula MOOC—CHR—N(CH 2 COOM) 2 , where R is a C 1-12 -alkyl and M is an alkali metal, the process including: preparing an aqueous solution containing the glycine-N,N-diacetic acid compound; concurrently passing the aqueous solution and air into a spray-drying apparatus; atomizing the aqueous solution by feeding the aqueous solution onto a rotating disk or by compressing the aqueous solution with a pump to a pressure of ≧20 bar absolute, to obtain fine liquid droplets; and drying the droplets, to obtain the spray-dried powder, where a temperature gradient between the aqueous solution and the air is in a range from 70 to 350° C., and a content of the glycine-N,N-diacetic acid compound in the aqueous solution is ≧84% by weight, based on a total weight of the dry mass. |