Fertilizers & Chemicals Ltd.

Shimon Epstein

Dahlia Simeona Greidinger

Liuba Cohen Nee Girshowitsh

The present invention relates to a method for the manufacture of an improved ureaform fertilizer. The method consists in the condensation of urea and formaldehyde carried out in a controlled system having a pH between 3.5 and 4.2 wherein the overall concentration of the reagents is in the range of 20 to 40% by weight. The ratio between the reagents is between 1.2 to 1.5 moles of urea to 1 mole of formaldehyde and the temperature of the reaction is kept between 15.degree. C. to 40.degree. C. Examples of preferred controlled systems are H.sub.3 PO.sub.4 -KH.sub.2 PO.sub.4 and H.sub.3 PO.sub.4 -NH.sub.4 H.sub.2 PO.sub.4. The method can also be performed in a continuous manner giving rise to an overall quantitative yield, and being temperature self-regulating. The ureaform obtained by the method has an activity index of over 75 and excellent physical properties.

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Kiryat Motzkin, Israel

Shimon Epstein