胡敏酸酒精沉淀分级及各级分特性研究

采用酒精沉法，将泥炭胡敏酸分成７个级分，研究了各级分胡敏酸的热解特性、絮凝极限和光学性质。结果表明，酒精沉淀分级法是按分子量大小、缩合程度的高低将胡敏酸分成较均一的级分，而对胡敏酸的性质、结构等无破坏作用。泥炭胡敏酸以级分１为最多，其次是级分７，分别占原样胡敏酸的２２．９３％，９．２０％，级分４最少，仅占３．６０％．级分１的分子缩合度和颗粒大小比原样胡敏酸大

Study on the Fractionation of Humic Acid by Alcohol Precipitation and Properties of the Fractions

Humic acid extracted from peat was classified into seven fractions by alcohol precipitation technique for the analysis of thermolysis,flocculation limit and some optical properties.The results showed that the humic acid was somewhat evenly fractionated by alcohol precipitation according to condensation degree and molecular mass,whereas its nature and structure were not affected.Of all the fractions,fraction 1 was the most and fraction 7 the second,accounting for 22.9 and 9.2 percent of the original humic acid,respectively;and fraction 4 was the least,which only accounted for 3.6 percent.The condensation degree and the molecular particle size of fraction 1 were larger than those of the original humic acid.