Studies on the Characteristics of Humic Acid and its Utilizations. () Utilizations of Humic Acid (Nitrohumates)

摘要

The adaptabilities of various nitrohumates (-K, -Na and -NH4 salt) as a soil conditioner and a raw material for soluble phosphatic fertilizer were studied. 1. Nitrohumates (especially-NH4 salt) protect the soil from fissures and control the phosphoric acid adsorptive functions of soils considerably. 2. Most effective nitrohumic acids as a soil conditioner were prepared with 15% HNO3 solution composed of five times of original humic acids (by weight) at 80?é for 2 hrs under continuous stirring. 3. When 50% (by weight) of NH4-nitrohumate were added to apatites in water and boiled for 2 hrs, maximum 26% of P2O5(apatite contains 37% of P2O5) were changed into water soluble forms.