| 摘要 |
Heretofore, two approaches have been utilized to improve storage stability, particularly a reduction in the tendency for caking during storage, of freshly prepared urea particles: (1) treat the surface of freshly prepared urea particles with conditioning agents, or (2) incorporate, within the urea particles, by means of addition to the urea melt, certain chemicals which act as hardening agents. This invention is directed to approach (2) supra, and by way of coincidence, to a third approach, to wit, utilizing a gelling clay as said additive to also act as an in situ suspending agent in instances wherein said treated urea is utilized in the subsequent production of suspension type fertilizers. The particular class of additives are clays of the group comprising channelized 2:1 clay minerals, namely attapulgite (palygorskite) and sepiolite and are added to the urea in relatively small quantities such that, although they impart the improved desired characteristics, they do not detract substantially from other properties thereof.
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