PROCESS FOR PREPARATION HUMIC PLANT GROWTH STIMULANT Russian patent published in 1994 - IPC

FIELD: agriculture. SUBSTANCE: lignite is treated with strong solution of alkaline metal hydroxide in weight mixture ratio of (0.5-0.8): 1.0 under heating. The heating of the reaction mixture is carried out at two stages. First, the reaction mixture is heated to 100 C to dehydrate it, and further heat treatment of the reaction mixture is carried out at 180-220 C for 10-20 min. It is preferable that dehydration of the reaction mixture be carried out in vacuum at 60-130 KPa. When high-ash lignite is used, the product resulted from two-stage heat treatment is extracted with water, the extractant is separated from ash constituents and evaporated. EFFECT: higher growth-promoting effect. 2 cl, 1 tbl