Preparation of ureaform
    4.
    发明授权
    Preparation of ureaform 失效
    脲型的制备

    公开(公告)号:US4123570A

    公开(公告)日:1978-10-31

    申请号:US811434

    申请日:1977-06-29

    CPC分类号: C05C9/02

    摘要: Preparation of ureaform granules. A concentrated aqueous solution of a urea-formaldehyde condensate is mixed with a catalyst which at normal temperature effects virtually no acid condensation, but a elevated temperature releases sufficient strong acid to effect the acid condensation in a few seconds. The mixture of solution and catalyst is sprayed over solid ureaform particles maintained in spaced interrelationship and at such a temperature that the catalyst is decomposed and effects acid condensation, whereby the sprayed particles are coated with a layer of ureaform and dried.

    摘要翻译: 尿素颗粒的制备 将脲 - 甲醛缩合物的浓缩水溶液与常温下的催化剂混合,几乎不发生酸冷凝,但升高的温度释放足够的强酸,以在几秒钟内发生酸冷凝。 将溶液和催化剂的混合物喷雾在保持间隔相互关系的固体脲型颗粒上,并在催化剂分解并进行酸冷凝的温度下喷射,其中喷雾的颗粒被涂覆有尿素层并干燥。