PRODUCING METHOD OF HUMIC ACID AND FULVIC ACID CONTAINED IN LIGNITE USING OXIDATION BY NITRIC ACID

摘要

The present invention relates to a producing method for humic acid and fulvic acid contained in lignite. The present invention comprises the following steps: adding 10-40% of an aqueous nitric acid solution into lignite to allow a solid-to-liquid ratio (S:L) to range from 0.5 to 3, and oxidizing by reacting at 10-90°C for 2-48 hours. The method in the present invention ensures to produce humic acid and fulvic acid in a better quality by efficiently altering carbons in the humic acid and fulvic acid contained in the lignite through an oxidation of lignite using nitric acid, thereby being able to produce the fulvic acid and the humic acid in high yield.