Formation and description of humic acid

Humic acid is a type of organic substance created and accumulated through the decomposition and transformation of animal and plant remains (mainly plant remains) by microorganisms and a series of geochemical processes. Its total amount is staggeringly large, in the trillions of tons. There are traces of it in rivers, lakes, seas, soil, coal mines, and most of the earth's surface. Due to its widespread existence, it has a great impact on the earth, involving carbon cycle, mineral migration and accumulation, soil fertility, ecological balance, etc. The total amount of humic acid contained in soil is the largest, but the content in it is less than one percent on average. The total amount contained in brackish water is also not small, but the concentration is lower. The most promising humic acid resources for development and utilization are coals with low calorific value, such as peat, lignite and weathered coal. Among them, the humic acid content reaches 10-80%. my country's coal reserves are very rich. According to data, there are 5 billion tons of peat and 126.5 billion tons of lignite. There are no statistical data on weathered coal. In this sense, the production and application of humic acid can also be said to be an aspect of coal chemical industry.
The basic structure of humic acid macromolecules is an aromatic ring and an alicyclic ring, with functional groups such as carboxyl, hydroxyl, carbonyl, quinone, and methoxy groups attached to the ring.