Effects of Methane Fermentation on Spectral Properties of Fulvic Acid Extracted from Peat through Liquid Acid Precipitation

Table 1

Fulvic acid in different experiment groups.

Test group	Peat (g)	Methane fermentation	Acid precipitation
FMS	40	√	Sulfuric acid
FMN	40	√	Nitric acid
FMH	40	√	Hydrochloric acid
FMP	40	√	Phosphoric acid
FS	40		Sulfuric acid
FN	40		Nitric acid
FH	40		Hydrochloric acid
FP	40		Phosphoric acid